Power sensitive wireless communication radio management

This application is a continuation of U.S. application Ser. No. 14/958,902, filed Dec. 3, 2015, the contents of which are incorporated herein by reference.

BACKGROUND

One feature of a mobile or wearable device is the device's operational use time, i.e. the duration for which the device may be continuously used as a function of the device's stored energy (e.g. battery) capacity. Most mobile devices are designed to automatically search or poll for signals from various wireless communication networks (e.g. cellular phone, Wi-Fi, 3G, etc.) and/or to search or poll for other devices using various wireless communication technologies (e.g., Bluetooth®, Wi-Fi Direct®, etc.), regardless of what other devices the mobile device is currently connected. When sending or receiving data, mobile devices typically use such wireless communication networks or technologies. However, each different type of wireless technology uses a different amount of electrical power. Typically, mobile devices are configured to transfer data using the fastest data connection available (i.e., the data connection having the greatest available bandwidth).

SUMMARY

In some examples a method includes predicting, by a wearable device, an amount of data to be transferred from a computing device, and determining, by the wearable device, based on the amount of data, a particular wireless communication technology from a plurality of wireless communication technologies of the wearable computing device predicted to use the least amount of power for transferring the data. The method may also include determining, by the wearable device, whether the wearable device can connect to the computing device using the particular wireless communication technology, and, responsive to determining that the wearable device can connect to the computing device using the particular wireless communication technology, transferring, by the wearable device and using the particular wireless communication technology, the data.

In some example, a method includes determining, by a wearable device, whether the wearable device is connected to a computing device using a first wireless communication technology from a plurality of wireless communication technologies of the wearable device, and responsive to determining that the wearable device is not connected to the computing device using the first wireless communication technology, determining, by the wearable device, whether the wearable device is currently being worn. The method may also include, responsive to determining that the wearable device is currently being worn: determining, by the wearable device, whether the wearable device can connect to the computing device using a second wireless communication technology from the plurality of wireless communication technologies, wherein the first wireless communication technology uses less power to establish and maintain a connection with the computing device than the second wireless communication technology, and, responsive to determining that the wearable device can connect to the computing device using the second wireless communication technology, establishing, by the wearable device, a connection to the network using the second wireless communication technology.

In another example, a wearable device includes one or more processors, a plurality of communication components each associated with a respective wireless communication technology, wherein at least a first communication component from the plurality of communication components is active, and wherein at least a second communication component from the plurality of communication components is inactive, one or more motion sensors configured to detect motion of the wearable device and generate, based on the detected motion, motion data, and a storage device configured to store at least one module. The at least one module may be operable by the one or more processors to: determine whether the wearable device is connected to a computing device using the first communication component, responsive to determining that the wearable device is not connected to the computing device using the first communication technology, determine, based on the motion data, whether the wearable device is currently being worn. The module may be further operable by the one or more processors to: responsive to determining that the wearable device is currently being worn: activate the second communication component, determine whether the wearable device can connect to the computing device using the second communication component, wherein the first communication component uses less power to establish and maintain a wireless connection with the computing device than the second communication component, and, responsive to determining that the wearable device can connect to the computing device using the second communication component, establish the wireless connection to the computing device using the second communication component.

The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

<figref idref="DRAWINGS">FIG. 1</figref> is a conceptual diagram illustrating an example system that includes computing devices that intelligently manage communication components in accordance with one or more techniques of this disclosure.

<figref idref="DRAWINGS">FIG. 2</figref> is a block diagram illustrating an example configuration of a wearable device that intelligently manages communication components in accordance with one or more techniques of this disclosure.

<figref idref="DRAWINGS">FIG. 3</figref> is a table illustrating example communication component states, in accordance with one or more techniques of this disclosure.

<figref idref="DRAWINGS">FIGS. 4 and 5</figref> are flowcharts illustrating example operations of a wearable device, in accordance with one or more techniques of this disclosure.

DETAILED DESCRIPTION

In general, the disclosure is directed to techniques for power sensitive intelligent wireless communication radio management, which may reduce power consumption by a computing device (e.g., cellular phone, tablet computer, computerized watch or eyeglasses, etc.) when sending or receiving data. For instance, a computing device commonly has more than one wireless communication radio, where each radio may be capable of receiving and/or transmitting a signal (e.g. cellular, Wi-Fi, 3G, 4G, LTE, Bluetooth®, etc.). Each wireless communication radio may use a different amount of power for sending or receiving a particular amount of data. The computing device may determine how much data is likely to be transferred and may select a wireless communication radio to use for the data transfer based on the total amount of power likely to be required to complete the data transfer. That is, techniques of this disclosure may enable a computing device to minimize the amount of electrical power required to transfer data by intelligently selecting the wireless communication radio used to perform the data transfer.

In some examples, in addition to intelligently selecting the wireless communication radio, the computing device may selectively activate, deactivate, or adjust reconnection attempt parameters of one or more wireless communication radios based on a current context of the computing device. The current context may include one or more connections to other computing devices, detected movement of the computing device, computing device usage history, current location of the computing device, current charge level or state of the computing device, activity state of a user of the computing device, current time, etc. By actively managing the power state and/or reconnection policies of the wireless communication radios, the computing device may reduce the power usage of the computing device, thereby increasing the battery life of the computing device or enabling the computing device to utilize a smaller battery to achieve the same battery life.

Throughout the disclosure, examples are described wherein a computing device and/or computing system may analyze information (e.g., locations, speeds, accelerations) associated with the computing device and information (e.g., captured images, communications, calendars, files and notes) associated with the user of the computing device only if the computing device and/or the computing system receives explicit permission from the user of the computing device to analyze the information. For example, in situations discussed below in which the computing device and/or computing system may collect or may make use of information associated with the user and the computing device, the user may be provided with an opportunity to provide input to control whether programs or features of the computing device and/or computing system can collect and make use of user images and information (e.g., information about a user's e-mail, a user's social network, social actions or activities, profession, a user's preferences, or a user's past and current location), or to dictate whether and/or how the computing device and/or computing system may receive content that may be relevant to the user. In addition, certain data may be treated in one or more ways before it is stored or used by the computing device and/or computing system, so that personally-identifiable information is removed. For example, a user's identity may be treated so that no personally identifiable information can be determined about the user, or a user's geographic location may be generalized where location information is obtained (such as to a city, ZIP code, or state level), so that a particular location of a user cannot be determined. Thus, the user may have control over how information is collected about the user and used by the computing device and/or computing system.

<figref idref="DRAWINGS">FIG. 1</figref> is a conceptual diagram illustrating an example system that includes computing devices that intelligently manage communication components in accordance with one or more techniques of this disclosure. The example system of <figref idref="DRAWINGS">FIG. 1</figref> includes computing device <b>100</b>, wearable computing device <b>102</b>, and network <b>104</b>. Computing device <b>100</b> and wearable computing device <b>102</b> may be companion devices. That is, both computing device <b>100</b> and wearable computing device <b>102</b> may be associated with a single user and one device, such as wearable computing device <b>102</b>, may require connectivity to the other device (e.g., computing device <b>100</b>) in order to be fully functional.

In the example of <figref idref="DRAWINGS">FIG. 1</figref>, computing device <b>100</b> is a smartphone. However, other examples of, computing device <b>100</b> may be a cellular phone, a personal digital assistant (PDA), a laptop computer, a tablet computer, a portable gaming device, a portable media player, an e-book reader, a watch, or another type of portable or mobile device. In the example of <figref idref="DRAWINGS">FIG. 1</figref>, wearable computing device <b>102</b> is a wearable computing device (e.g., a computerized watch or so-called smart watch device). However, in other examples, wearable computing device <b>102</b> may be a mobile phone, a tablet computer, a personal digital assistant (PDA), a laptop computer, a portable gaming device, a portable media player, an e-book reader, a television platform, an automobile computing platform or system, a fitness tracker, or any other type of mobile or non-mobile computing device capable of intelligently managing wireless communication radios in accordance with one or more of the techniques described herein.

Network <b>104</b> represents any public or private communication network, for instance, a cellular, Wi-Fi, and/or other type of network for transmitting data between computing devices. Computing device <b>100</b> and wearable computing device <b>102</b> may send and receive data across network <b>100</b> using any suitable communication techniques. For example, computing device <b>100</b> may be operatively coupled to network <b>104</b> using network link <b>105</b> and wearable computing device <b>102</b> may be operatively coupled to network <b>104</b> by network link <b>107</b>. Network <b>104</b> may include network hubs, network switches, network routers, and other network devices that are operatively inter-coupled thereby providing for the exchange of information between computing device <b>100</b> and wearable computing device <b>102</b>. In some examples, network links <b>105</b> and <b>107</b> may be Ethernet, Asynchronous Transfer Mode (ATM) network, or other network connections and such connections may be wireless and/or wired connections, including cellular network connections.

Computing device <b>100</b> and wearable computing device <b>102</b> may also exchange information without traversing network <b>104</b> by, for example, using direct link <b>109</b>. Direct link <b>109</b> may be any network communication protocol or mechanism capable of enabling two computing devices to communicate directly (i.e., without requiring a network switch, hub, or other intermediary network device), such as Bluetooth®, Wi-Fi Direct®, near-field communication, etc.

As shown in <figref idref="DRAWINGS">FIG. 1</figref>, computing device <b>100</b> is a mobile computing device. However, in other examples, computing device <b>110</b> may be a tablet computer, a personal digital assistant (PDA), a laptop computer, a portable gaming device, a portable media player, an e-book reader, a watch, a television platform, an automobile navigation system, a wearable computing device (e.g., a headset device, watch device, eyewear device, a glove device), or other type of computing device. Computing device <b>100</b> may include presence-sensitive display <b>106</b> and communication (COMM) components <b>108</b>.

Presence-sensitive display <b>106</b> of computing device <b>100</b> may function as an input device for computing device <b>110</b> and as an output device. Presence-sensitive display <b>106</b> may be implemented using various technologies. For instance, presence-sensitive display <b>106</b> may function as an input device using a presence-sensitive input component, such as a resistive touchscreen, a surface acoustic wave touchscreen, a capacitive touchscreen, a projective capacitance touchscreen, a pressure sensitive screen, an acoustic pulse recognition touchscreen, or another presence-sensitive display technology. Presence-sensitive display <b>106</b> may function as an output (e.g., display) device using any one or more display components, such as a liquid crystal display (LCD), dot matrix display, light emitting diode (LED) display, organic light-emitting diode (OLED) display, e-ink, or similar monochrome or color display capable of outputting visible information to a user of computing device <b>100</b>. Communication components <b>108</b> may include wireless communication devices capable of transmitting and/or receiving communication signals such as a cellular radio, a 3G radio, a Bluetooth® radio, or a Wi-Fi radio.

As shown in <figref idref="DRAWINGS">FIG. 1</figref>, wearable computing device <b>102</b> may include power management module <b>110</b>, communication (COMM) selection module <b>112</b>, and communication (COMM) components <b>114</b>A-<b>114</b>N (collective, “communication components <b>114</b>”). Examples of communication components <b>114</b> include wireless communication devices capable of transmitting and/or receiving communication signals such as a cellular radio, a 3G radio, a Bluetooth® radio, or a Wi-Fi radio. Modules <b>110</b> and <b>112</b> may perform operations described herein using software, hardware, or a mixture of both hardware and software residing in and executing on wearable computing device <b>102</b>. Wearable computing device <b>102</b> may execute modules <b>110</b> and <b>112</b> with multiple processors. Wearable computing device <b>102</b> may execute modules <b>110</b> and <b>112</b> as a virtual machine on underlying hardware.

In a default setting, wearable computing device <b>102</b> may operate with all communication components <b>114</b> activated (e.g., turned on and consuming electrical power). In accordance with techniques of the disclosure, wearable computing device <b>102</b> may automatically deactivate and/or activate individual communication components <b>114</b>, which may preserve stored electrical energy. Wearable computing device <b>102</b> may determine which of communication components <b>114</b> to activate and use based on a context of wearable computing device <b>102</b>. The context may include any combination of factors, such as whether computing device <b>100</b> is reachable from wearable computing device <b>102</b> using a particular one of communication components <b>114</b>, a type of data being transferred between computing device <b>100</b> and wearable computing device <b>102</b>, a current time of day, an amount of charge remaining in a battery of wearable computing device <b>102</b>, a predicted amount of future usage before a predicted recharge time, a monetary cost to transfer data, etc.

Wearable computing device <b>102</b> may prioritize relatively lower power communication components <b>114</b> over relatively higher power communication components <b>114</b>. For example, Bluetooth® radios typically require less power to operate than Wi-Fi radios, which, in turn, typically require less power to operate than cellular radios. In such an example, communication selection module <b>112</b> may activate a Bluetooth® radio (e.g., configure communication component <b>114</b>A to be active) and deactivate other communication components <b>114</b> of wearable computing device (i.e., configure the other communication components <b>114</b> to be inactive), including a Wi-Fi radio (e.g., communication component <b>114</b>B) and a cellular radio (e.g., communication component <b>114</b>C).

However, in examples, where wearable computing device <b>102</b> is paired to computing device <b>100</b> (e.g., configured as a companion device to computing device <b>100</b>), communication selection module <b>112</b> may activate a relatively higher power communication component so as to maintain a data connection with computing device <b>100</b>. For example, if wearable computing device <b>102</b> is not communicatively coupled to computing device <b>100</b> using Bluetooth® (e.g., computing device <b>100</b> is outside of the range of Bluetooth®, the Bluetooth® radio of computing device <b>100</b> is turned off, etc.), communication selection module <b>112</b> may deactivate communication component <b>114</b>A and activate communication component <b>114</b>B, a Wi-Fi radio, even though the Wi-Fi radio typically uses more power than a Bluetooth® radio. Similarly, if wearable computing device <b>102</b> is not communicatively coupled to computing device <b>100</b> using either Bluetooth® or Wi-Fi, communication selection module <b>112</b> may deactivate communication components <b>114</b>A and <b>114</b>B, and activate communication component <b>114</b>C (e.g., a cellular radio) and attempt to connect to computing device <b>100</b> using cellular. While this example describes deactivating the Bluetooth® radio (e.g., communication component <b>114</b>A), in other examples, communication component <b>114</b>A remains active and continues to monitor for available Bluetooth® devices, including computing device <b>100</b>. In such examples, if wearable computing device <b>102</b> is able to establish a Bluetooth® connection to computing device <b>100</b>, communication selection module <b>112</b> may deactivate the other communication components <b>114</b> (i.e., configure the other communication components <b>114</b> to be inactive).

Power management module <b>110</b> may monitor various characteristics of wearable computing device <b>102</b> and the data being exchanged between computing device <b>100</b> and wearable computing device <b>102</b>. For example, power management module <b>110</b> may monitor a current charge level of a battery or other power component of wearable computing device <b>102</b>. If power management module <b>110</b> predicts that the battery will run out of power prior to a predicted time at which wearable computing device <b>102</b> will be connected to a charger, power management module <b>110</b> may cause communication selection component to prioritize power savings over connectivity to computing device <b>100</b>. For example, power management module <b>110</b> may cause communication selection module <b>112</b> to disable all radios, including Bluetooth®, so as to enable wearable computing device <b>102</b> to at least display a current time until the predicted recharge time.

Power management module <b>110</b> may also configure a Wi-Fi scan rate based on an amount of charge remaining in the battery and based on the connection state of communication components <b>114</b>. For example, if wearable computing device <b>102</b> is unable to establish a Bluetooth® connection to computing device <b>100</b> and if wearable computing device <b>102</b> is running off of batter power (i.e., not currently plugged in or charging), power management module <b>100</b> may configure the Wi-Fi radio (e.g., communication component <b>114</b>B) to perform a Wi-Fi scan at a reduced periodic interval, such as once every three minutes as compared to if wearable computing device <b>102</b> were plugged in or charging (e.g., once every thirty seconds). As another example, if wearable computing device is connected to the Internet and/or computing device <b>100</b> via a cellular radio (e.g., communication component <b>114</b>C) connection, power management module <b>110</b> may further reduce the frequency of Wi-Fi scans to, for example, once every ten minutes.

Computing device <b>100</b> and wearable computing device <b>102</b> may exchange data, such as voice data (e.g., for a telephone call), audio data (e.g., music), video data (e.g., movies), image data (e.g., still pictures), application data, sensor data, etc. In various instances, wearable computing device <b>102</b> may select a particular radio to use for data transfer based on any combination of one or more of the type of data, a predicted amount of data to be transferred, and an amount of power required to transmit a unit of data between computing device <b>100</b> and wearable computing device <b>102</b>. For example, while Bluetooth® may require less power to maintain a connection to computing device <b>100</b>, Bluetooth® may require more power than Wi-Fi to transmit relatively larger amount of data. That is, Bluetooth® may have a higher per megabyte power cost than Wi-Fi. Similarly, cellular may have a higher per megabyte power cost than Wi-Fi, but may have a lower per megabyte power cost than Bluetooth®. In some examples, the estimated power cost includes a predicted amount of power required to establish a connection using the particular wireless communication technology, such as the amount of power required to perform a Wi-Fi scan and connect to a Wi-Fi network, the amount of power required to search for a cellular network and connect to the cellular network, etc. In this way, wearable computing device <b>102</b> may select one of communication components <b>114</b> so as to minimize the total amount of power used to transmit data to computing device <b>100</b> or another computing device.

Techniques of this disclosure may provide one or more advantages. For example, techniques of this disclosure may enable a computing device to intelligently manage wireless communication radios in a manner that may reduce power usage, thereby increasing the battery life of the computing device and/or enabling the computing device to include a smaller battery. By determining which wireless communication technology to use for transferring data based on a total amount of power required to transfer the data, a computing device may utilize a relatively higher power radio to transfer data than typical computing devices because the relatively higher power radio may actually consume less power than a relatively lower power radio due to increase bandwidth and a lower per megabyte power cost. In this way, techniques of this disclosure may enable a computing device to meet strict power requirements while still maintaining connectivity and providing a good user experience.

<figref idref="DRAWINGS">FIG. 2</figref> is a block diagram illustrating an example configuration of a wearable device that intelligently manages communication components in accordance with one or more techniques of this disclosure. As shown in the specific example of <figref idref="DRAWINGS">FIG. 2</figref>, wearable device <b>202</b> includes one or more communication components <b>214</b>, one or more processors <b>230</b>, a presence-sensitive display <b>232</b>, a power component <b>238</b>, one or more input components <b>240</b>, one or more output components <b>242</b>, one or more sensor components <b>244</b>, and one or more storage devices <b>250</b>. Communication channels <b>260</b> may interconnect each of the components <b>214</b>, <b>230</b>, <b>232</b>, <b>238</b>, <b>240</b>, <b>242</b>, <b>244</b>, and <b>250</b> for inter-component communications (physically, communicatively, and/or operatively). In some examples, communication channels <b>260</b> may include a system bus, a network connection, an inter-process communication data structure, or any other method for communicating data. Communication components <b>214</b>, power management module <b>210</b>, and communication selection module <b>212</b> of <figref idref="DRAWINGS">FIG. 2</figref> may provide similar capability and functionality to wearable device <b>202</b> as communication components <b>114</b>, power management module <b>110</b>, and communication selection module <b>112</b> of <figref idref="DRAWINGS">FIG. 1</figref>.

As shown in <figref idref="DRAWINGS">FIG. 2</figref>, wearable device <b>202</b> may include power component <b>238</b>. In some examples, power component <b>238</b> may be a battery. Power component <b>238</b> may store electric power and provide electric power to one or more components of wearable device <b>202</b>. Examples of power component <b>238</b> may include, but are not necessarily limited to, batteries having zinc-carbon, lead-acid, nickel cadmium (NiCd), nickel metal hydride (NiMH), lithium ion (Li-ion), and/or lithium ion polymer (Li-ion polymer) chemistries. In some examples, power component <b>238</b> may have a limited capacity (e.g., 100-3000 mAh).

One or more storage devices <b>250</b> within computing device <b>100</b> may store information required for use during operation of wearable device <b>202</b>. Storage device <b>250</b>, in some examples, has the primary purpose of being a short term and not a long term computer-readable storage medium. Storage device <b>250</b> on wearable device <b>202</b> may be a volatile memory and therefore not retain stored contents if powered off. Examples of volatile memories include random access memories (RAM), dynamic random access memories (DRAM), static random access memories (SRAM), and other forms of volatile memories known in the art. Storage device <b>250</b> may further be configured for long-term storage of information as non-volatile memory space and retain information after power on/off cycles. Examples of non-volatile memory configurations include magnetic hard discs, optical discs, floppy discs, flash memories, or forms of electrically programmable memories (EPROM) or electrically erasable and programmable (EEPROM) memories. In some examples, processors <b>230</b> on wearable device <b>202</b> read and execute instructions stored by storage device <b>250</b>. In the example of <figref idref="DRAWINGS">FIG. 2</figref>, storage device <b>250</b> of wearable device <b>202</b> includes power management module <b>210</b>, communication (COMM) selection module <b>212</b>, signal detect module <b>252</b>, and wear detection module <b>254</b>. In addition, modules <b>210</b>, <b>212</b>, <b>252</b>, and <b>254</b> may store information within storage device <b>250</b> during program execution.

One or more processors <b>230</b> may implement functionality and/or execute instructions within wearable device <b>202</b>. For example, processors <b>230</b> may process instructions stored in storage device <b>250</b> that execute the functionality of modules <b>210</b>, <b>212</b>, <b>252</b>, and <b>254</b>.

Presence-sensitive display <b>232</b> of wearable device <b>202</b> includes display component <b>234</b> and presence-sensitive input component <b>236</b>. Display component <b>234</b> may be a screen at which information is displayed by presence-sensitive display <b>232</b> and presence-sensitive input component <b>236</b> may detect an object at and/or near display component <b>234</b>. As one example range, presence-sensitive input component <b>234</b> may detect an object, such as a finger or stylus that is within two inches or less of display component <b>234</b>. Presence-sensitive input component <b>235</b> may determine a location (e.g., an [x, y] coordinate) of display component <b>234</b> at which the object was detected. In another example range, presence-sensitive input component <b>235</b> may detect an object six inches or less from display component <b>234</b> and other ranges are also possible. Presence-sensitive input component <b>236</b> may determine the location of display component <b>234</b> selected by a user's finger using capacitive, inductive, and/or optical recognition techniques. In some examples, presence-sensitive input component <b>236</b> also provides output to a user using tactile, audio, or video stimuli as described with respect to display component <b>234</b>. In the example of <figref idref="DRAWINGS">FIG. 2</figref>, presence-sensitive display <b>232</b> may present a user interface.

While illustrated as an internal component of wearable device <b>202</b>, presence-sensitive display <b>232</b> may also represent and an external component that shares a data path with wearable device <b>202</b> for transmitting and/or receiving input and output. For instance, in one example, presence-sensitive display <b>232</b> represents a built-in component of wearable device <b>202</b> located within and physically connected to the external packaging of wearable device <b>202</b> (e.g., a screen on a mobile phone). In another example, presence-sensitive display <b>232</b> represents an external component of wearable device <b>202</b> located outside and physically separated from the packaging or housing of wearable device <b>202</b> (e.g., a monitor, a projector, etc. that shares a wired and/or wireless data path with wearable device <b>202</b>).

Presence-sensitive display <b>232</b> of wearable device <b>202</b> may receive tactile input from a user of wearable device <b>202</b>. Presence-sensitive display <b>232</b> may receive indications of the tactile input by detecting one or more tap or non-tap gestures from a user of wearable device <b>202</b> (e.g., the user touching or pointing to one or more locations of presence-sensitive display <b>232</b> with a finger or a stylus pen). Presence-sensitive display <b>232</b> may present output to a user. Presence-sensitive display <b>232</b> may present the output as a graphical user interface, which may be associated with functionality provided by various functionality of wearable device <b>202</b>. For example, presence-sensitive display <b>232</b> may present various user interfaces of components of a computing platform, operating system, applications, or services executing at or accessible by wearable device <b>202</b> (e.g., an electronic message application, a navigation application, an Internet browser application, a mobile operating system, etc.). A user may interact with a respective user interface to cause wearable device <b>202</b> to perform operations relating to one or more the various functions.

Presence-sensitive display <b>232</b> of wearable device <b>202</b> may detect two-dimensional and/or three-dimensional gestures as input from a user of wearable device <b>202</b>. For instance, a sensor of presence-sensitive display <b>232</b> may detect a user's movement (e.g., moving a hand, an arm, a pen, a stylus, etc.) within a threshold distance of the sensor of presence-sensitive display <b>232</b>. Presence-sensitive display <b>232</b> may determine a two or three dimensional vector representation of the movement and correlate the vector representation to a gesture input (e.g., a hand-wave, a pinch, a clap, a pen stroke, etc.) that has multiple dimensions. In other words, presence-sensitive display <b>232</b> can detect a multi-dimension gesture without requiring the user to gesture at or near a screen or surface at which presence-sensitive display <b>232</b> outputs information for display. Instead, presence-sensitive display <b>232</b> can detect a multi-dimensional gesture performed at or near a sensor which may or may not be located near the screen or surface at which presence-sensitive display <b>232</b> outputs information for display.

Wearable device <b>202</b> may include one or more input components <b>240</b> that wearable device <b>202</b> uses to receive input. Examples of input are tactile, audio, image and video input. Input components <b>240</b> of wearable device <b>202</b>, in one example, includes a presence-sensitive display, touch-sensitive screen, voice responsive system, a microphone or any other type of device for detecting input from a human or machine. In some examples, input components <b>240</b> include one or more sensor components <b>244</b>. Numerous examples of sensor components <b>244</b> exist and include any input component configured to obtain environmental information about the circumstances surrounding wearable device <b>202</b> and/or physiological information that defines the activity state and/or physical well-being of a user of wearable device <b>202</b>. For example, sensor components <b>244</b> may include movement sensors (e.g., accelerometers), temperature sensors, position sensors (e.g., a gyro), pressure sensors (e.g., a barometer), proximity sensors (e.g., an inferred sensor), ambient light detectors, heart-rate monitors, location sensors (GPS components, Wi-Fi components, cellular components), and any other type of sensing component (e.g., microphone, a still camera, a video camera, a body camera, eyewear, or other camera device that is operatively coupled to wearable device <b>202</b>, infrared proximity sensor, hygrometer, and the like). Wearable device <b>202</b> may use sensor components <b>244</b> to obtain contextual information associated with wearable device <b>202</b> and a user. In some examples, one or more of power management module <b>210</b>, communication selection module <b>212</b> and wear detection module <b>254</b> may rely on the sensor information obtained by sensor components <b>244</b>.

Wearable device <b>202</b> may include one or more output devices <b>230</b> that wearable device <b>202</b> uses to provide output. Examples of output are tactile, audio, still image and video output. Output components <b>230</b> of wearable device <b>202</b>, in one example, includes a presence-sensitive display, sound card, video graphics adapter, speaker, liquid crystal display (LCD), or any other type of device for generating output to a human or machine.

In accordance with the techniques of this disclosure, communication selection module <b>212</b> may select one or more communication components <b>214</b> to utilize for connection to another computing device (e.g., computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref>) and/or for sending or receiving data (e.g., over the Internet, to the other computing device, etc.) in a manner so as to attempt to minimize total power consumption. As shown in <figref idref="DRAWINGS">FIG. 2</figref>, communication selection module <b>212</b> includes payload determination module <b>256</b> and connection determination module <b>258</b>.

In instances where wearable device <b>202</b> is attempting to establish a connection with another computing device (e.g., computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref>), communication selection module <b>212</b> may use a relatively low power one of communication components <b>214</b> (e.g., a Bluetooth® radio) and attempt to connect to computing device <b>100</b> using a direct wireless connection (e.g., wireless link <b>109</b> of <figref idref="DRAWINGS">FIG. 1</figref>). That is, communication selection module <b>212</b> may be configured to initially attempt to establish a connection with computing device <b>100</b> using a lowest powered one of communication components <b>214</b>. When attempting to establish a connection with computing device <b>100</b>, the Bluetooth® radio may be in a “listen” mode where the Bluetooth® radio detects if any other Bluetooth® devices are reachable.

Connection determination module <b>258</b> may determine if the Bluetooth® radio detects computing device <b>100</b> and, if so, causes wearable device <b>202</b> to establish a Bluetooth® connection to computing device <b>100</b>. If connection determination module <b>258</b> determines that computing device <b>100</b> is not reachable via Bluetooth®, communication selection module <b>212</b> may activate another one of communication components <b>214</b> for establishing the connection with computing device <b>100</b>. For example, wearable device <b>202</b> may be preconfigured to attempt to connect to network <b>104</b> of <figref idref="DRAWINGS">FIG. 1</figref> using a Wi-Fi radio and, if unable to connect using the Wi-Fi radio, connect to network <b>104</b> using a cellular radio. That is, wearable device <b>202</b> may be preconfigured to initiate a wireless connection to computing device <b>100</b> and/or the Internet using the wireless communication radio that requires the least amount of power to establishing and/or maintain such a connection.

In attempting to establish a network connection with the Wi-Fi radio, communication selection module <b>212</b> may cause the Wi-Fi radio to perform a network scan. The one of communication components <b>214</b> that corresponds to the Wi-Fi radio scans to determine which, if any, Wi-Fi networks are available. Connection determination module <b>258</b> may analyze the list of available Wi-Fi networks and determine if any are “known” Wi-Fi networks, i.e., whether the service set identifier (“SSID”) of any of the available Wi-Fi networks corresponds to Wi-Fi network configuration information stored at wearable device <b>202</b> such that wearable device <b>202</b> may establish a connection to the Wi-Fi network. If one of the available Wi-Fi networks is a known Wi-Fi network, connection determination module <b>258</b> attempts to establish a connection to the known Wi-Fi network.

If none of the available Wi-Fi networks is a known Wi-Fi network or if connection determination module <b>258</b> is unable to establish a connection with a known Wi-Fi network, communication selection module <b>212</b> may place the Wi-Fi radio in a low power or “sleep” mode for an amount of time and attempt to establish a network connection using another one of communication components <b>214</b>. Communication selection module <b>212</b> may be configured to select the other one of communication components <b>214</b> based on an estimated amount of power required to establish and maintain a network connection using the particular wireless communication technology. For example, communication selection module <b>212</b> may be preconfigured to next attempt to establish a network connection using one of communication components <b>214</b> that corresponds to a cellular radio because the cellular radio requires more power to establish and maintain a network connection than Bluetooth® or Wi-Fi, but less power than another wireless communication technology. In examples where wearable device <b>202</b> establishes a cellular network connection (e.g., to computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref>), communication selection module <b>212</b> may leave the Bluetooth® radio powered on and configured to “listen” for other Bluetooth devices.

The Wi-Fi radio may be placed in the low power state for an amount of time determined based on user preferences and/or the connection state of one or more of communication components <b>214</b> in an attempt to provide a good user experience while minimizing the amount of power used. For example, power management module <b>210</b> may place the Wi-Fi radio in the low power state for two minutes, three minutes, five minutes, or ten minutes. The duration of the low power state may be based, in part, on the connection state of one or more other communication components <b>214</b>. For example, if wearable device <b>202</b> is connected to a network using a cellular radio, power management module <b>210</b> may increase the duration of the low power mode so as to reduce the number of Wi-Fi reconnection attempts (which may be power expensive) because the user experience is sufficient when connected via cellular that power management module <b>210</b> prioritizes power savings over quickly establishing a Wi-Fi network connection. After the amount of time elapses, communication selection module <b>212</b> may activate the Wi-Fi radio and again attempt to establish a Wi-Fi network connection. In this way, communication selection module <b>212</b> may dynamically adjust the Wi-Fi scan rate based on the network connection status of other communication components <b>214</b> of wearable device <b>202</b> in addition to the connection status of the Wi-Fi radio.

Power management module <b>210</b> may also adjust the Wi-Fi scan rate based on the power and/or connection state of other components of wearable device <b>202</b>, including one or more sensors <b>244</b>. For example, as it is power expensive to perform a Wi-Fi scan, power component <b>238</b> and/or one or more of communication components <b>214</b> may increase in temperature. However, certain ones of sensors components <b>244</b> or communication components <b>214</b> may be thermally sensitive such that they may not perform as well outside of a preferred thermal range. In particular, antennas associated with various communication components <b>214</b> and/or sensor components <b>244</b> may have decreased performance outside of the preferred thermal range. As such, power management module <b>210</b> may monitor power states of various components of wearable device <b>202</b> and/or a current temperature of one or more antennas of wearable device <b>202</b>. Based on the power state and/or temperature, power management module <b>210</b> may adjust the Wi-Fi scan rate in an attempt to keep the current temperature of wearable device <b>202</b> within the preferred thermal range while the particular communication components <b>214</b> and sensor components <b>244</b> are powered on. For example, power management module <b>210</b> may increase the duration of the low power mode (i.e., increase the time between Wi-Fi scans), which may reduce the temperature of wearable device <b>202</b>, which, in turn, may maintain the performance of the antennas associated with the particular communication components <b>214</b> and sensor components <b>244</b>.

In some examples, power management module <b>210</b> adjusts the Wi-Fi scan rate based on whether wearable device <b>202</b> is currently connected to a charger. For example, power management module <b>210</b> may determine that power component <b>238</b> is currently charging and, in response, prioritize connectivity over power and/or thermal concerns. That is, power management module <b>210</b> may increase the Wi-Fi scan rate (i.e., decrease the duration of the low power mode), establish a cellular connection, etc. In this way, in instances where wearable device <b>202</b> is a companion device to computing device <b>100</b>, wearable device <b>202</b> prioritizes connectivity to the companion device over power concerns such that wearable device <b>202</b> is synchronized with the companion device when wearable device <b>202</b> is removed from the charger.

However, while wearable computing device is charging, power component <b>238</b> may heat up, which may increase the temperature of wearable device <b>202</b> and reduce the performance of various antennas of wearable device <b>202</b>. In order to mitigate the thermal issues, power management module <b>210</b> may monitor a current temperature of various components of wearable device <b>202</b> and adjust the charging rate of power component <b>238</b>. By reducing the charging rate of power component <b>238</b>, power management module <b>210</b> may reduce the temperature of wearable device <b>202</b>, which may maintain the desired performance of the antennas of wearable device <b>202</b>.

Communication selection module <b>212</b> may also power on/off various communication components <b>214</b> based on movement of wearable device <b>202</b> and/or whether wearable device <b>202</b> is currently “donned” by a user (i.e., is currently being worn by the user or is on the body of the user). Wear detection module <b>254</b> may analyze sensors data from one or more sensor components <b>244</b> to determine whether wearable device <b>202</b> is currently being worn and an amount of time that has elapsed since wearable device <b>202</b> last moved. In examples where sensor components <b>244</b> includes one or more of a heart rate monitor, a galvanic skin response senor, or other sensor that can detect whether wearable computing device is in contact with a user's skin, wear detection module <b>254</b> may analyze the sensor information to determine if wearable device <b>202</b> is currently being worn. For example, if the heart rate monitor provides heart rate information to wear detection module <b>254</b>, wear detection module <b>254</b> can determine if the heart rate information is valid heart rate information (e.g., indicates a heart rate greater than zero beats per minute, less than 250 beats per minute, etc.) and, in response to determining that the hear rate information is valid, determine that wearable device <b>202</b> is currently being worn. As another example, wear detection module <b>254</b> may analyze data from the galvanic skin response sensor to determine if a user is currently wearing wearable device <b>202</b> (e.g., based on a current conductance detected by the galvanic skin response sensor).

Wear detection module <b>254</b> may also determine whether wearable device <b>202</b> is currently being worn using motion and/or position sensors (e.g., accelerometer, gyroscopes, etc. of sensor components <b>244</b>). For example, wear detection module <b>254</b> may monitor movement patterns detected by sensor components <b>244</b> and determine whether the movement patterns correspond to known movements (e.g., of a limb) of a user. If the movement patterns correspond to known movements, wear detection module <b>254</b> may determine that wearable computing device is currently being worn. However, in various instances, wear detection module <b>254</b> may determine that wearable device <b>202</b> is currently being worn even if the movement patterns do not correspond to known movements. Instead, wear detection module <b>254</b> may determine that any motion of wearable device <b>202</b> indicates that wearable device <b>202</b> is currently being worn. Similarly, wear detection module <b>254</b> determine that wearable device <b>202</b> is not currently being worn if wearable device <b>202</b> has not moved for a threshold amount of time (e.g., one minute, three minutes, five minutes, etc.).

Responsive to determining that wearable device <b>202</b> is not being worn, power management module <b>210</b> may power off one or more communication components <b>214</b>, place one or more communication components <b>214</b> into a low power or reduced power mode, and/or adjust the frequency at which one or more communication components <b>214</b> attempt to establish a network connection. For example, power management module <b>210</b> may power off any Wi-Fi and cellular radios while leaving a Bluetooth® radio powered on.

Determining whether or not wearable computing device <b>202</b> is being worn requires a non-zero amount of power, which may offset any power savings achieved by adjusting the power states and/or operating characteristics of communication components <b>214</b>. As such, wear detection module <b>254</b> may adjust how often wear detection module <b>254</b> performs off-body detection based on a likelihood that the user has removed wearable device <b>202</b> (e.g., based on historical user behavior, time of day, etc.) and a power cost to maintain the current operating characteristics of communication components <b>214</b>. Historical user behavior may include previous usage information (e.g., how a user directly interacts with wearable device <b>202</b>), notification history (e.g., time and frequency of received notifications), etc.

For example, if wear detection module <b>254</b> determines, based on prior user behavior, that a user is likely to have removed wearable device <b>202</b>, wear detection module <b>254</b> may perform the off-body detection techniques to determine if the user has actually removed wearable device <b>202</b>. However, if wear detection module <b>254</b> determines, based on prior user behavior, that the user is likely to put wearable device <b>202</b> back on within a relatively short period of time (e.g., five minutes), wear detection module <b>254</b> may determine that the amount of power required to perform the off-body detection may be greater than or equal to the amount of power required to power the radios until the user is likely to don wearable device <b>202</b>. In response, wear detection module <b>254</b> may not to perform off-body detection and, instead, maintain the current power state of communication components <b>214</b>.

Wearable computing device <b>202</b> may be configured to ensure a minimal amount of functionality until the next time at which wearable device <b>202</b> is predicted be connected to a charger unless a user overrides or otherwise causes wearable device <b>202</b> to run out of power prior to the next time wearable device <b>202</b> is charged. Power management module <b>210</b> may monitor the user's activity and the amount of power utilized by one or more communication components <b>214</b> during the discharge cycle and use this information to predict an amount of time remaining before power component <b>238</b> runs out of power. That is, power management module <b>201</b> may keep track of how many minutes each of communication components <b>214</b> were active during the discharge cycle and how much power each of communication components <b>214</b> used while active and power on/off various communication components <b>214</b> to predict how many minutes of battery life remain.

Power management module <b>210</b> may determine the estimated amount of operating time remaining based on the current charge level of power component <b>238</b>, a historical power usage of wearable device <b>202</b>, and/or a predicted future power usage of wearable device <b>202</b>. The historical power usage may include the average power usage since wearable device <b>202</b> was last disconnected from a charger, an average power usage for the particular context (e.g., day of the week, location, scheduled calendar events, temperature, current activity, time, average amount of data sent/received, etc.), an average power usage for a particular amount of time (e.g., average daily power usage over the previous thirty days), etc. The predicted future power usage may be based on the average power usage for the particular context and/or predicted future context of wearable device <b>202</b>. In some examples, power management module <b>210</b> may determine an amount of time each of communication components <b>214</b> are active during the current discharge cycle. Based on the amount of active time of each communication component <b>214</b>, power management module <b>210</b> may estimate how much power each communication component <b>214</b> has used during the discharge cycle.

If power management module <b>210</b> predicts that power component <b>238</b> will run out of power prior to the next predicted charging time, communication selection module <b>212</b> may adjust the operating characteristics of communication components <b>214</b>. For example, based on the amount of active time of each communication component <b>214</b>, power management module <b>210</b> may disable relatively higher power communication components <b>214</b> in an attempt to reduce the rate of power drain and maintain at least partial functionality of wearable device <b>202</b> until wearable device <b>202</b> is predicted to be connected to a charger. As other examples, power management module <b>210</b> may reduce the power usage rate by reducing the Wi-Fi scan rate, disabling all communication components <b>214</b>, disabling various sensor components <b>244</b>, disabling presence-sensitive input component <b>236</b>, etc.

In some instances, power management module <b>210</b> may determine a current amount of power being used by one or more communication components <b>214</b>. For example, power management module <b>210</b> may monitor the power consumption (e.g., the number of milliamp hours) currently being consumed by each communication component <b>214</b>. If power management module <b>210</b> determines that one communication component <b>214</b> (e.g., a Wi-Fi radio) is consuming more power than expected, power management module <b>210</b> may notify communication selection module <b>212</b> and cause communication selection module <b>212</b> to select a different one of communication components <b>214</b> for the network connection.

Communication selection module <b>212</b> may select which one of communication components <b>214</b> to use to transfer data based on characteristics of the data that is going to be sent from and/or received by wearable device <b>202</b>. Each communication component <b>214</b> may use a different amount of power for sending or receiving a particular amount of data. Communication selection module <b>212</b> may determine how much data is likely to be transferred and may select one of communication components <b>214</b> to use for the data transfer based on the total amount of power likely to be required to complete the data transfer. Payload determination module <b>256</b> of communication selection module <b>212</b> may predict an amount of data to be transferred based on a type of data (e.g., audio, video, text, etc.), an application associated with the data transfer (e.g., a video player application, a web browser, etc.), a priority assigned to the data being transferred (e.g., by a developer), an amount of bandwidth requested by the application associated with the data transfer, a length of a data queue, etc.

As one example, payload determination module <b>256</b> may determine that the file type of the data being transferred corresponds to video data. IN such an example, payload determination module <b>256</b> may be configured to determine that, when transferring video data, a large amount of data is typically transferred to wearable device <b>202</b>. In response to determining that a relatively large amount of data is predicted to be transferred, communication selection module <b>212</b> may prioritize a network connection using a relatively higher power wireless radio but that has a relatively large amount of bandwidth (e.g., a Wi-Fi radio) over a network connection using a relatively low power wireless radio but that has a relatively small amount of bandwidth (e.g., a Bluetooth® radio). In such an example, communication selection module <b>212</b> may determine that it is more power efficient to use the Wi-Fi radio to transfer the data than it is to use the Bluetooth® radio to transfer the data. In instances where wearable device <b>202</b> is a companion device to computing device <b>100</b>, wearable device <b>202</b> may establish a direct Wi-Fi connection with computing device <b>100</b> (i.e., a Wi-Fi connection that does not include an intermediary network element, such as a wireless router).

As another example, payload determination module <b>256</b> may determine that the data to be transferred is audio data associated with an incoming phone call. As voice audio data for a phone call is relatively low bandwidth, communication selection module <b>212</b> may power off a Wi-Fi radio and, instead, establish a Bluetooth connection with a device sending the audio data (e.g., to computing device <b>100</b>). In another example, the data being transferred may include a flag or other indication of whether the data requires high-bandwidth connectivity. For example, computing device <b>100</b> is transferring music to wearable device <b>202</b>, a music application executing on computing device <b>100</b> may send, to wearable device <b>202</b>, initial data that includes a flag indicating that the data to be transferred is music data and/or requires high bandwidth connectivity. In response to receiving the indication of the higher bandwidth requirement, communication selection module <b>212</b> may activate the Wi-Fi radio and initiate a Wi-Fi scan in attempt to connect to computing device <b>100</b> over Wi-Fi rather than Bluetooth®. In this way, communication selection module <b>212</b> may dynamically select one or more communication components <b>214</b> to use for transferring data based on characteristics of the data being transferred and may reduce the amount of power used to transfer the data.

<figref idref="DRAWINGS">FIG. 3</figref> is a table <b>300</b> illustrating example communication component states, in accordance with one or more techniques of this disclosure. For purposes of illustration, wireless communication state table <b>300</b> is described below with respect to computing device <b>100</b> and wearable computing device <b>102</b> of <figref idref="DRAWINGS">FIG. 1</figref>, although other devices may be configured consistent with table <b>300</b>.

Table <b>300</b> illustrates example Wi-Fi radio power states based on whether wearable computing device <b>102</b> is connected to computing device <b>100</b> using Bluetooth, whether wearable computing device <b>102</b> is currently being worn by a user, and a power state of wearable computing device <b>102</b>. In particular, table <b>300</b> illustrates four distinct connection states. In state one, wearable computing device <b>102</b> is connected to computing device <b>100</b> using Bluetooth®. In this state, wearable computing device <b>102</b> may be configured to use Bluetooth® to transfer data and to disable the Wi-Fi radio regardless of whether wearable computing device <b>102</b> is being worn and regardless of the power state of wearable computing device <b>102</b>.

In the second state, wearable computing device <b>102</b> is not connected to computing device <b>100</b> via Bluetooth®, but is in a power saving mode (e.g., to ensure that wearable computing device <b>102</b> may provide a minimal amount of functionality until wearable computing device <b>102</b> is next connected to a charger). Because wearable computing device <b>102</b> is not connected via Bluetooth®, but is in the power saving mode, wearable computing device powers off the Wi-Fi radio, regardless of whether wearable computing device <b>102</b> is currently being worn. In some examples, wearable computing device <b>102</b> does not perform off-body detection which in the power saving mode.

State three is illustrated in <figref idref="DRAWINGS">FIG. 3</figref> such that wearable computing device <b>102</b> is not connected to computing device <b>100</b> via Bluetooth®, but is currently charging (i.e., is currently connected to a charger). In state three, wearable computing device is configured to turn on the Wi-Fi radio regardless of whether a user is currently wearing wearable computing device <b>102</b>. By turning on Wi-Fi, wearable computing device <b>102</b> may be more frequently synchronized with computing device <b>100</b> without reducing the battery life of wearable computing device <b>102</b>.

In the fourth state, wearable computing device <b>102</b> is not connected to computing device <b>100</b> using Bluetooth®, is in a “normal” power mode (i.e., is not currently charging and is not in a power saving mode), and is currently being worn by a user. In this state, wearable computing device <b>102</b> may be turned on, but may perform Wi-Fi scans at a reduced frequency as compared to when wearable computing device <b>102</b> is connected to a charger, which may reduce power usage and increase the amount of time a user may use wearable computing device <b>102</b> before charging wearable computing device <b>102</b>.

<figref idref="DRAWINGS">FIG. 4</figref> is a flowchart illustrating an example operation of a computing device, in accordance with one or more techniques of this disclosure. The example operation shown in <figref idref="DRAWINGS">FIG. 4</figref> is described below with respect to computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref> and wearable device <b>202</b> of <figref idref="DRAWINGS">FIG. 2</figref>, although other computing devices may perform the operations of <figref idref="DRAWINGS">FIG. 4</figref>.

In the example of <figref idref="DRAWINGS">FIG. 4</figref>, wearable device <b>202</b> may determine if a user is wearing wearable device <b>202</b> (<b>400</b>). For example, wear detection module <b>254</b> wearable device <b>202</b> may analyze motion data generated by an accelerometer, gyroscope, or other motion sensor of wearable device <b>202</b> to determine if wearable device <b>202</b> is being worn. For example, if the motion patterns correspond to know user movements, wear detection module <b>254</b> may determine that a user is currently wearing wearable device <b>202</b> (“YES” branch of <b>400</b>). As another example, if the motion data indicates that wearable device <b>202</b> has been stationary for a threshold amount of time (e.g., 60 seconds, 5 minutes, 20 minutes, etc.), wear detection module <b>254</b> may determine that the user is not currently wearing wearable device <b>202</b> (“NO” branch of <b>400</b>).

In instances where wear detection module <b>254</b> determines that wearable device <b>202</b> is not being worn (“NO” branch of <b>400</b>), communication selection module <b>212</b> may ensure that a Bluetooth® radio (e.g., one of communication components <b>214</b>) is turned on/enabled and monitor for a Bluetooth® connection to a companion device, such as computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref> (<b>402</b>). Further power management module <b>210</b> may turn off any Wi-Fi and cellular radios (<b>404</b>), which may reduce power consumption while wearable device <b>202</b> is not being worn.

In instances where wear detection module <b>254</b> determines that wearable device <b>202</b> is being worn (“YES” branch of <b>400</b>), connection determination module <b>258</b> of communication selection module <b>212</b> may determine whether wearable device <b>202</b> is connected to a companion device (e.g., computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref>) via Bluetooth® (<b>406</b>). If connection determination module <b>258</b> determines that wearable device <b>202</b> is connected to the companion device (“YES” branch of <b>406</b>), power management module <b>210</b> powers off the Wi-Fi and cellular radios (<b>404</b>), which may save energy while wearable device <b>202</b> is connected to the companion device. Wearable device <b>202</b> may exchange data using the Bluetooth® connection with the companion device, including sending and receiving data to devices on the Internet, such that the Wi-Fi and cellular connections are not needed.

If connection determination module <b>258</b> determines that wearable device <b>202</b> is not connected to a companion device using Bluetooth® (“NO” branch of <b>406</b>), communication selection module <b>212</b> determines if a Wi-Fi radio (e.g., one of communication components <b>214</b>) should be woken up from a sleep state (i.e., activated, powered on, etc.) (<b>408</b>). In some examples, power management module <b>210</b> manages the wake-sleep cycle of the Wi-Fi radio so as to reduce power usage. For example, if connection determination module <b>258</b> determines that there is no known Wi-Fi network available, power management module <b>210</b> may cause the Wi-Fi radio to go into a “sleep” (i.e., low power or powered off) mode for a predetermined amount of time (e.g., 1 minute, 3 minutes, 5 minutes, etc.). As another example, if power management module <b>210</b> determines that the amount of power remaining in power component <b>238</b> is insufficient to power wearable device <b>202</b>, at the current discharge rate, until the predicted next time wearable device <b>202</b> is going to be connected to a charger, power management module <b>210</b> may disable the Wi-Fi radio, as well as other components, such as the cellular radio, until wearable device <b>202</b> is connected to the charger or until power management module <b>210</b> predicts that there is sufficient power remaining in power component <b>238</b> to keep wearable device <b>202</b> operating until wearable device <b>202</b> is predicted to be connected to a charger. In such examples, communication selection module <b>212</b> determines that the Wi-Fi radio should not be woken from the sleep state (i.e., should not transition to a higher power mode from a lower power mode) and should not initiate a Wi-Fi scan to detect available Wi-Fi networks (“NO” branch of <b>408</b>).

If communication selection module <b>212</b> determines that the Wi-Fi radio should not be woken up from the sleep state (“NO” branch of <b>408</b>), communication selection module <b>212</b> may activate a cellular radio of wearable device <b>202</b> (<b>420</b>) and attempt to establish a cellular Internet connection to a companion device (<b>422</b>). That is, if wearable device <b>202</b> is unable to connect to the companion device using Bluetooth® or Wi-Fi, communication selection module <b>212</b> may attempt to connection to the companion device using a relatively higher power communication technology, such as cellular. However, even if a network connection to the companion device is established using the cellular radio (e.g., via network <b>104</b>), wearable device <b>202</b> continues to determine if it is being worn (<b>400</b>) and continues to attempt to connect to the companion device using a relatively lower power radio (<b>402</b>-<b>418</b>).

If communication selection module <b>212</b> determines that the Wi-Fi- radio should be woken up from the sleep state (“YES” branch of <b>408</b>), power management module <b>210</b> activates the Wi-Fi radio (<b>410</b>) and connection determination module <b>258</b> causes the Wi-Fi radio to perform a Wi-Fi scan (<b>412</b>). In performing the Wi-Fi scan, the Wi-Fi radio detects available Wi-Fi networks at the current location of wearable device <b>202</b>. Connection determination module <b>258</b> determines if any of the available Wi-Fi networks are “known” Wi-Fi networks or if wearable device <b>202</b> is otherwise able to connect to one of the available Wi-Fi networks (<b>414</b>). Known Wi-Fi networks may include a direct Wi-Fi connection to the companion device (i.e., a connection to computing device <b>100</b> that does not traverse network <b>104</b>). If connection determination module <b>258</b> determines that one of the Wi-Fi networks is a “known” Wi-Fi network (“YES” branch of <b>414</b>), connection determination module <b>258</b> attempts to connect to the Wi-Fi network (<b>416</b>). In instances where wearable device <b>202</b> is able to establish the connection to the Wi-Fi network and to the companion device, wearable device <b>202</b> may be configured to continue to determine if it is currently being worn (<b>400</b>) and may continue to attempt to connect to the companion device using a relatively lower power wireless radio technology, such a Bluetooth® (<b>420</b>-<b>404</b>). In some examples, even though wearable device <b>202</b> is able to connect to a Wi-Fi network, wearable device <b>202</b> may not be able to establish a connection with the companion device using the Wi-Fi network. In such examples, connection determination module <b>258</b> may operate as if wearable device <b>202</b> was unable to connect to any available Wi-Fi network.

In examples where connection determination module <b>258</b> is unable to connect via Wi-Fi because there are no known Wi-Fi networks or for other reasons (“NO” branch of <b>414</b>), power management module <b>210</b> puts the Wi-Fi radio into a sleep state (<b>418</b>) for a preconfigured period of time, enables the cellular radio (<b>420</b>), and attempts to connect to the Internet using the cellular radio (<b>422</b>). The preconfigured period of time may be dynamically adjusted based on a current amount of power remaining in power component <b>238</b>, whether wearable device <b>202</b> is connected to a charger, a power usage rate of wearable device <b>202</b>, a type of data being or to be transferred, among other factors. In this way, wearable device <b>202</b> may intelligently select which wireless communication technology to use to connect to a companion device (e.g., computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref>), which may reduce the amount of power used by wearable device <b>202</b>.

<figref idref="DRAWINGS">FIG. 5</figref> is a flowchart illustrating an example operation of a computing device, in accordance with one or more techniques of this disclosure. The example operation shown in <figref idref="DRAWINGS">FIG. 5</figref> is described below with respect to computing device <b>100</b> of <figref idref="DRAWINGS">FIG. 1</figref> and wearable device <b>202</b> of <figref idref="DRAWINGS">FIG. 2</figref>, although other computing devices may perform the operations of <figref idref="DRAWINGS">FIG. 4</figref>. Further, the example operation of <figref idref="DRAWINGS">FIG. 5</figref> may be combined with the example operation of <figref idref="DRAWINGS">FIG. 4</figref> such that wearable device <b>202</b> may determine which wireless communication technology to use not only based on how much power is required for each wireless radio to establish and maintain a connection to the companion device and/or the Internet, but also based on a predicted amount of power required to exchange data with the companion device or another device available via the Internet. In the example operation illustrated in <figref idref="DRAWINGS">FIG. 5</figref>, it is assumed that wearable device <b>202</b> is connected to computing device <b>100</b> using Bluetooth® and than wearable device <b>202</b> and computing device <b>100</b> are transferring data between each other.

In determining which wireless communication technology to use for transferring data, payload determination module <b>256</b> of wearable device <b>202</b> may determine what type of data is going to be transferred (<b>500</b>). For example, if a user launches a music application at wearable device <b>202</b>, payload determination module <b>256</b> may determine that the user is likely to transfer audio data. As another example, if a user launches a streaming video viewing application, payload determination module <b>256</b> may determine that the user is likely to transfer video data. In yet another example, payload determination module <b>256</b> may determine the type of data to be transferred based on a file extension (e.g., “.mp4”, “.avi”, “.jpg”, “.txt”, “.zip”, etc.). In some instances, payload determination module <b>256</b> may analyze an initial portion of data (e.g., a first one, ten, fifty, etc. data packets) and determine, based on the contents of the initial portion of data (e.g., packet header information, data stored in the payload portion of the packet, etc.), the type of data being transferred.

Payload determination module <b>256</b> may predict, based on the type of the data being transferred, a size (i.e., amount) of data that is going to be transferred (<b>502</b>) and determine if the amount of data is greater than a threshold amount (<b>504</b>). Various wireless communication technologies utilize different amounts of power for transferring the same amount of data. For example, Bluetooth® may require a relatively small amount of power to maintain a connection, but a relatively large amount of power to transmit data whereas Wi-Fi may require a relatively large amount amount of power to establish and maintain a connection, but only use a relatively small amount of power to transmit data. That is, each different wireless connection technology may use a different amount of power to transmit a megabyte of data such that a wireless communication technology that may be considered to typically use a relatively large amount of power may actually be more power efficient when transferring relatively large amounts of data than a different wireless communication technology that may be considered to typically use a relatively small amount of power.

Further, communication selection module <b>212</b> may determine which wireless communication technology to use to transfer the data based on factors other than power requirements, such as a monetary cost to transfer the data using each wireless communication technology. For example, transferring data using a cellular connection may be monetarily more expensive than transferring data using Wi-Fi such that, even though transferring the data using the cellular connection may require less power, communication selection module <b>212</b> determines that the data should be transferred using Wi-Fi because the monetary cost of the cellular connection outweighs the power savings. As another example, even though Wi-Fi may typically require less power to transfer the data, communication selection module <b>212</b> may determine that there is a limited amount of bandwidth available Wi-Fi network such that transferring the data may take longer than initially predicted, which may result in using more power than a different wireless connection technology. In such examples, communication selection module <b>212</b> may switch to a different wireless connection technology for transferring the data. In general, communication selection module <b>212</b> may apply a weighting to the various factors when determining which wireless communication technology to use for transferring the data.

The threshold amount of data may be different for each different type of wireless communication technology and may be different when comparing different wireless technologies. For example, if wearable device <b>202</b> is able to connection to computing device <b>100</b> using Bluetooth® and Wi-Fi, communication selection module <b>202</b> may configure the threshold such that data transfers of less than one megabyte should be transferred using Bluetooth® and data transfers greater than one megabyte should be transferred using Wi-Fi. However, if Bluetooth® is not available, but Wi-Fi and cellular are available (e.g., wearable device <b>202</b> is currently connected via cellular), communication selection module <b>202</b> may configure the threshold such that data transfers of less than ten megabytes should be transferred using cellular and data transfers greater than ten megabytes should be transferred using Wi-Fi. In yet another example, if Bluetooth® and cellular are available, but Wi-Fi is not available, communication selection module <b>202</b> may configure the threshold such that data transfers of less than three megabytes should be transferred using Bluetooth and data transfers greater than three megabytes should be transferred using cellular. The threshold values provided are only examples and any threshold value that may enable wearable device <b>202</b> to reduce the total power required to transfer the data may be used.

If payload determination module <b>256</b> determines that the predicted size of the data transfer is not greater than a threshold amount of data (“NO” branch of <b>504</b>), power management module <b>210</b> determines that it is more power efficient to transfer the data using the established Bluetooth® connection and wearable device transfers the data using Bluetooth® (<b>506</b>). If payload determination module <b>256</b> that the predicted size of the data transfer is greater than the threshold amount of data (“YES”) branch of <b>504</b>, power management module <b>210</b> determines that it is more power efficient to transfer the data using Wi-Fi, connection determination module <b>258</b> determine whether a Wi-Fi connection is available (<b>508</b>). If there is Wi-Fi available (“YES” branch of <b>508</b>), communication selection module <b>256</b> establishes the Wi-Fi connection, if needed, and wearable device <b>202</b> transfers the data using Wi-Fi (<b>510</b>).

If there is no Wi-Fi connection available (“NO” branch of <b>508</b>), communication selection module <b>212</b> determines whether to transfer the data using a cellular connection (<b>512</b>). For example, if wearable device <b>202</b> has an unlimited cellular data plan and power management module <b>210</b> predicts that it will require less power to transfer the data using cellular than using Bluetooth® (“YES” branch of <b>512</b>), communication selection module <b>212</b> may determine to transfer the data using cellular and wearable device <b>202</b> may transfer the data using cellular (<b>514</b>). However, if transferring data using cellular data is monetarily expensive and/or if power management module <b>210</b> predicts that it will require less power to transfer the data using Bluetooth® than cellular (“NO” branch of <b>512</b>), communication selection module <b>212</b> may determine to transfer the data using Bluetooth® and wearable device <b>202</b> may transfer the data using Bluetooth® (<b>506</b>).

Example 1

A method comprising: predicting, by a wearable device, an amount of data to be transferred from a computing device; determining, by the wearable device, based on the amount of data, a particular wireless communication technology from a plurality of wireless communication technologies of the wearable computing device predicted to use the least amount of power for transferring the data; determining, by the wearable device, whether the wearable device can connect to the computing device using the particular wireless communication technology; and, responsive to determining that the wearable device can connect to the computing device using the particular wireless communication technology, transferring, by the wearable device and using the particular wireless communication technology, the data.

Example 2

The method of example 1, wherein predicting the amount of data to be transferred is based on one or more of a type of the data, header information of at least one packet of the data, an application associated with the data transfer, a priority assigned to the data being transferred, and an amount of bandwidth requested by the application associated with the data transfer.

Example 3

The method of any of examples 1-2, wherein the particular wireless communication technology is a first wireless communication technology, the method further comprising: responsive to determining that the wearable device cannot connect to the computing device using the first wireless communication technology: determining, by the wearable device, a second wireless communication technology predicted to use a lowest amount of power of the plurality of wireless communication technologies other than the first wireless communication technology; and transferring, by the wearable computing device, the data using the second wireless communication technology.

Example 4

The method of any of examples 1-3, further comprising: while transferring the data: determining, by the wearable device, whether a different one of the wireless communication technologies is predicted to use less power to transfer a remaining portion of the data than the particular wireless communication technology; and responsive to determining that the different wireless communication technology from the wireless communication technologies is predicted to use less power to transfer the remaining portion of the data, transferring, by the wearable device, the remaining portion of the data using the different the wireless communication.

Example 5

The method of any of examples 1-4, wherein: the particular wireless communication technology uses less power to transfer a particular amount of data than one or more other wireless communication technologies from the plurality of wireless communication technologies, and the particular wireless communication technology uses more power to establish and maintain the connection to the computing device than at least one other wireless communication technology of the plurality of communication technologies.

Example 6

The method of any of examples 1-5, wherein the particular wireless communication technology is one of Bluetooth, Wi-Fi, and cellular.

Example 7

A method comprising: determining, by a wearable device, whether the wearable device is connected to a computing device using a first wireless communication technology from a plurality of wireless communication technologies of the wearable device; responsive to determining that the wearable device is not connected to the computing device using the first wireless communication technology, determining, by the wearable device, whether the wearable device is currently being worn; responsive to determining that the wearable device is currently being worn: determining, by the wearable device, whether the wearable device can connect to the computing device using a second wireless communication technology from the plurality of wireless communication technologies, wherein the first wireless communication technology uses less power to establish and maintain a connection with the computing device than the second wireless communication technology; and responsive to determining that the wearable device can connect to the computing device using the second wireless communication technology, establishing, by the wearable device, a connection to the network using the second wireless communication technology.

Example 8

The method of example 7, further comprising: responsive to determining that the wearable device is connected to the computing device using the first wireless communication technology: predicting, by a wearable device, an amount of data to be transferred from the computing device; determining, by the wearable device, based on the amount of data, that the second wireless communication technology is predicted to use less power to transfer the data than the first wireless communication technology; and responsive to determining that the second wireless communication technology is predicted to use less power to transfer the data, transferring, by the wearable device and using the second wireless communication technology, the data.

Example 9

The method of any of examples 7-8, further comprising: responsive to determining that the wearable device is not being worn, monitoring, by the wearable device, for a connection to the computing device using the first wireless communication technology.

Example 10

The method of any of examples 7-9, further comprising: responsive to determining that the wearable device cannot connect to the computing device using the second wireless communication technology, determining, by the wearable device, whether the wearable device can connect to the computing device using a third wireless communication technology, wherein the second wireless communication technology uses less power to establish and maintain a connection with the computing device than the third wireless communication technology; and responsive to determining that the wearable device can connect to the computing device using the third wireless communication technology: establishing, by the wearable device, the connection to the computing device using the third wireless communication technology; and configuring a radio associated with the second wireless communication technology to operate in a reduced power mode.

Example 11

The method of any of examples 7-10, further comprising: determining, by the wearable device, a rate at which power is being used by the wearable device; predicting, by the wearable device, a future time at which the wearable device is going to be connected to a charger; and responsive to predicting, based on the rate at which power is being used by the wearable device and the future time, that a power component of the wearable device is going to run out of power prior to the future time, disabling all wireless communication technology radios other than a radio for the first wireless communication technology.

Example 12

The method of any of examples 7-11, wherein the first communication technology is Bluetooth and wherein the second wireless communication technology is one of Wi-Fi and cellular.

Example 13

A wearable device comprising: one or more processors; a plurality of communication components each associated with a respective wireless communication technology, wherein at least a first communication component from the plurality of communication components is active, and wherein at least a second communication component from the plurality of communication components is inactive; one or more motion sensors configured to detect motion of the wearable device and generate, based on the detected motion, motion data; a storage device configured to store at least one module operable by the one or more processors to: determine whether the wearable device is connected to a computing device using the first communication component; responsive to determining that the wearable device is not connected to the computing device using the first communication technology, determine, based on the motion data, whether the wearable device is currently being worn; responsive to determining that the wearable device is currently being worn: activate the second communication component; determine whether the wearable device can connect to the computing device using the second communication component, wherein the first communication component uses less power to establish and maintain a wireless connection with the computing device than the second communication component; and responsive to determining that the wearable device can connect to the computing device using the second communication component, establish the wireless connection to the computing device using the second communication component.

Example 14

The wearable device of example 13, wherein the at least one module is further operable by the one or more processors to: responsive to determining that the wearable device is connected to the computing device using the first communication component: predict an amount of data to be transferred from the computing device; determine, based on the amount of data, that the second communication component is predicted to use less power to transfer the data than the first communication component; and responsive to determining that the second communication component is predicted to use less power to transfer the data, transfer, and using the second communication component, the data.

Example 15

The wearable device of example 14, wherein the at least one module is further operable by the one or more processors to predict the amount of data to be transferred based on one or more of a type of the data, header information of at least one packet of the data, an application associated with the data transfer, a priority assigned to the data being transferred, and an amount of bandwidth requested by the application associated with the data transfer.

Example 16

The wearable device of any of examples 14-15, wherein the at least one module is further operable by the one or more processors to: responsive to determining that the wearable device cannot connect to the computing device using the first communication component: determine that the second communication component is predicted to use a lowest amount of power of the plurality of communication components other than the first communication component; and transfer the data using the second communication component.

Example 17

The wearable device of example 16, wherein: the first communication component uses less power to transfer a particular amount of data than the second communication component, and the first communication component uses more power to establish and maintain the connection to the computing device than the second communication component.

Example 18

The wearable device of any of examples 13-17, wherein the at least one module is further operable by the one or more processors to: determine whether the wearable device is connected to a charger; and responsive to determining that the wearable device is connected to the charger, connect to the computing device using the second communication component.

Example 19

The wearable device of any of examples 13-18, wherein the at least one module is further operable by the one or more processors to: responsive to determining that the wearable device cannot connect to the computing device using the second communication component, determine whether the wearable device can connect to the computing device using a third communication component, wherein the second communication component uses less power to establish and maintain a connection with the computing device than the third communication component; and responsive to determining that the wearable device can connect to the computing device using the third communication component: establish the wireless connection to the computing device using the third communication component; and deactivate the second communication component.

Example 20

The wearable device of any of examples 133-198, further comprising: a power component configured to store power, wherein the at least one module is further operable by the one or more processors to: determine a rate at which power is being used by the wearable device; predict a future time at which the wearable device is going to be connected to a charger; and responsive to predicting, based on the rate at which power is being used by the wearable device and the future time, that the power component is going to run out of the power prior to the future time, disabling the plurality of communication components other than a the first communication component.

In one or more examples, the operations described may be implemented in hardware, software, firmware, or any combination thereof If implemented in software, the functions may be stored on or transmitted over, as one or more instructions or code, a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include computer-readable storage media, which corresponds to a tangible medium such as data storage media, or communication media including any medium that facilitates transfer of a computer program from one place to another, e.g., according to a communication protocol. In this manner, computer-readable media generally may correspond to (1) tangible computer-readable storage media which is non-transitory and does not include a signal or (2) a communication medium such as a signal or carrier wave. Data storage media may be any available media that can be accessed by one or more computers or one or more processors to retrieve instructions, code and/or data structures for implementation of the techniques described in this disclosure. A computer program product may include a computer-readable medium.

By way of example, and not limitation, such computer-readable storage media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage, or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if instructions are transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. It should be understood, however, that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transient media, but are instead directed to non-transient, tangible storage media. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

Instructions may be executed by one or more processors, such as one or more digital signal processors (DSPs), general purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term “processor,” as used herein may refer to any of the foregoing structure or any other structure suitable for implementation of the techniques described herein. In addition, in some aspects, the functionality described herein may be provided within dedicated hardware and/or software modules. Also, the techniques could be fully implemented in one or more circuits or logic elements.

The techniques of this disclosure may be implemented in a wide variety of devices or apparatuses, including a wireless handset, an integrated circuit (IC) or a set of ICs (e.g., a chip set). Various components, modules, or units are described in this disclosure to emphasize functional aspects of devices configured to perform the disclosed techniques, but do not necessarily require realization by different hardware units. Rather, as described above, various units may be combined in a hardware unit or provided by a collection of interoperative hardware units, including one or more processors as described above, in conjunction with suitable software and/or firmware.

Various examples have been described. These and other examples are within the scope of the following claims.