Method and system for automatic control in an interference cancellation device

The present invention relates to the field of communication, and more particularly to improving the signal fidelity of a communication device by canceling interference that occurs between two or more communication channels.

(Explanation of related application) This application was filed by Gebara and others on December 14, 2005, entitled "Method and System for Reducing Signal Interference," non-US. It is a partial continuation application while claiming the benefit of the priority of US Nonprovisional Patent Application Serial No. 11/30 2,896.

US Provisional Patent Application No. 11 / 302,896 was filed by Gebara and others on December 14, 2004, entitled "Electromagnetic Interference Wireless Canceller," US Provisional Patent. It claims the benefit of the priority of Application No. 60 / 635,817.

This application is further referred to as "Automatic Gain and Phase Control for an Interference Cancellation Device" filed by Kim and others on June 10, 2005. Claim the priority benefit of the entitled US Provisional Patent Application No. 60 / 689,467.

This application is further referred to as "Control Loop for Active Noise Canceller in Wireless Communication System" filed by Schmukler and others on July 6, 2005. Claim the priority benefit of the title US Provisional Patent Application No. 60 / 696,905.

This application is further entitled "Method and System for Embedded Detection of Electromagnetic Interference" filed by Stelliga and others on September 21, 2005. Claims the priority benefit of US Provisional Patent Application No. 60 / 719,055.

This application was further filed by Stelliga and others on September 23, 2005, "Method and System for Reducing Power Consumption". Claims the priority benefit of US Provisional Patent Application No. 60 / 720,324, entitled in an Interference Cancellation Device of a Wireless System).

All disclosures of the priority literature mentioned above are incorporated herein by reference.

Communication equipment used in wireless communication systems generally receives small signals and transmits large signals. There are many sources of noise in modern wireless communication systems. Many noise sources are included in transmitters and possibly multiple transmitters for devices including multiple communication devices operating simultaneously. Inadequate isolation between transmitters and receivers, interference from unwanted sources, wideband noise from the digital bus from the processor to the display device, and interference of these side lobes and even other signals within the wireless communication system. Contribute to the signal. Typical types of interference are commonly described as electromagnetic interference (EMI) or inadequate insulation. In EMI, interference is a radiated electromagnetic wave coupled within the receiver. If the component is poorly insulated, interference signals or noise will couple to electrical components, air or printed circuit board (PCB) leads.

EMI is a serious concern as wireless communication systems transmit and receive electromagnetic (EM) signals for communication data. Specific examples of such systems include mobile phones, wireless email services, pocketbell services, wireless data networks (eg, networks conforming to the IEEE standard 802.11a / b / g / n), satellite links, terrestrial microwaves, etc. There are wireless peripheral links (eg Bluetooth) cable television, broadcast television, and Global Positioning Systems (GPSs). The receiver in the wireless communication device undesirably receives the interfering signal in addition to the intended high frequency signal. High frequency signals intended to be received are referred to as "victim" signals. A signal that causes interference is referred to as an "invader" or "invader" signal. Thus, EMI degrades the signal fidelity of the victim signal and also reduces the high frequency reception quality. Typical sources of interference are, among other numbers, other high frequency circuits within the device itself, highway buses that carry data within the device itself, and other circuits within the device due to inadequate insulation. There are signals received and EMI generated outside the device. Even if the communication bands of the victim signal and the invader signal do not directly overlap each other, the out-of-band invader signal harms the victim signal, especially if the invader signal is significantly stronger than the victim signal. give.

EMI becomes suspicious when two or more high frequency services are performed on the same device, for example a mobile phone handset with multiple bands and work. In such a state, the signal transmitted for the high frequency first service interferes with the signal received for the high frequency second service. Such interference occurs even when two or more tasks use different frequency bands because the transmission power of the first signal is significantly affected by the reception power of the second signal. Harmful interference also occurs when energy leakage occurs from one high frequency device in the second high frequency device due to inadequate suppression of the subband signal. As a result, it is only part of the first service, the transmitted signal leaks into the second high frequency device, and the received signal causes interference problems.

In addition to EMI coming from another wireless service, EMI also comes from high-speed circuits that are close to the receiver. For example, mobile phones and high-speed speed buses transmit display data from processors to high-resolution displays. In most cases, it is desirable to increase the resolution of the display in view of the features of the product. However, the highway bus data ratio associated with the increased display resolution generally produces high levels of radial EMI. Highway buses include buses that perform high digital data rates, buses that switch signals quickly, or buses that switch signals frequently. That is, the bus signal rises and falls very quickly, as fast as the total amount of data processed in the actual fixed time.

For digital systems in wireless devices, device designers seek to increase the data rate or bandwidth of each path line, conductor or channel. Designers have increased bandwidth to support high display resolutions, high display update rates, high camera resolutions, increased digital memory capacity, integrated handheld computer features, integrated music and video functionality, and more. Also pursue. Faster data rates can also be achieved by designing buses with a reduced number of data, addresses, or control paths. Bus lane reduction will list the data rate of commonly existing routes that remain to support the total amount of information processing over a period of time. Therefore, in mobile phone equipment, improvements in displays, cameras and other subsystems will increase EMI and reduce the capabilities of high frequency receivers.

The impact of EMI increases when high-speed circuits are closed near high-frequency receivers. In particular, high-speed signals cause EMI emission. When a high-speed circuit is closed in the vicinity of a high-frequency receiver, the receiver receives the signal intended to be received even though it does not want to interfere.

Highway buses that radiate interference take multiple forms. For example, in the mobile telephone field described above, buses that carry display data are often embodied as flexible cables. Flexible cables are also called flexible circuits or ribbon cables. Flexible cables have multiple conductors, channels (typically copper conductors) embedded in, laminated, or laminated in flexible molding structures such as plastic or polymer films and even some other dielectric or insulating material. It will be printed.

A third source of EMI is a circuit or circuit element located near the victim channel or high frequency. A circuit or circuit element through which a signal flows, such as a signal on a highway bus, emits EMI. Typical examples of circuits that radiate problematic levels of EMI include voltage controlled oscillators (VCOs), phase-locked loops (PLLs), switch mode circuits, amplifiers, and other active or passive circuits or circuit elements. ..

In addition, designers may wish to improve the high frequency reception of wireless devices, for example facilitating the reception of weak high frequency signals in the field of mobile telephones. In other words, improving the reception of low power or noise signals provides another motivation for reducing interference or crosstalk, or otherwise processing. A weak high frequency signal has an intensity smaller than, for example, the noise level of EMI. Therefore, reducing EMI facilitates the reception of weak high frequency signals, or allows the operation of mobile phones or the use of other wireless communication devices in noisy environments.

Traditional passive filters have often been ineffective in dealing with EMI. In some cases, an active canceller helps calm the interference. One technique for actively canceling signal interference is to sample the invader signal in the form of simulating or emulating the interference signal, and processing the samples obtained to generate an emulation of the interference. Including doing. The cancel circuit subtracts the emulated interference signal from the reception victim signal damaged by the interference signal in order to generate a compensated or corrected signal with reduced interference.

Conventional techniques for sampling invader signals have often been inadequate. Distortions or errors associated with sampling the aggressor signal caused a loss of fit between the interference and the emulation of the interference. One technique for obtaining a sample of the invader signal is to tap the invader line directly. However, the resulting loss of power in the invader line for transmission is undesirable in many areas such as handheld radios, mobile phones or handsets (telephones, cordless phones, handsets). A direct tap on the invader line adversely affects the modularization of the device.

Interference sampling devices are generally placed near the source of the interference and some sources. This arrangement helps the sampling device to obtain a sample of the interfering signal and, moreover, avoids the sample of the high frequency signal. A careless sample of the high frequency signal results in the removal of the victim signal from the compensation signal in the cancel circuit, thereby degrading the quality of the compensation signal. In other words, conventional techniques for obtaining interfering samples often cumber the mounting position of the sampling element or impose difficult constraints on the mounting position.

In the field of handsets, sampling devices should generally be able to coexist due to the structure of the handset and its compact configuration. High frequency handsets, such as mobile phones, typically include a large number of components that design engineers may have difficulty integrating using traditional design techniques. The stringent placement requirements of traditional coherent sampling equipment have often increased design complexity. In other words, traditional interference sampling devices often fail to offer a sufficient level of design flexibility, resulting in placement constraints.

Another drawback of many prior arts for active EMI cancellation is poor management of power consumption. Active EMI cancelers consume an undesired high level of power that shortens battery life in the handset field. That is, conventional EMI cancellation techniques often draw large amounts of power from the cell phone's battery or other energy source when applied to a cell phone or other cell phone. Users generally consider extending battery life as a desirable feature of mobile wireless communication products. Therefore, reducing power consumption to increase the time to recharge the battery is always important to design engineers.

To handle these typical issues in this area, the ability of telecommunications equipment to handle, correct, or cancel signal interference is required. There is a need for compact devices for sampling invader signals and / or associated interference within communication devices such as mobile phone devices. In addition, there is a need for an interference sampling device that allows engineers to design modularity or flexibility. There is also a need for technology for means for controlling the gain and phase of the cancel signal by the active EMI canceller. In addition, there is a need for natural and continuously adaptive gain and phase compensation to handle any changes in the means by which the aggressor signal couples to the victim signal or any changes over time in the aggressor signal. is there. There is also a need for techniques for active EMI canceller control loops that avoid the interference associated with the desired received signal or add extra noise to the received signal. In addition, there is a need for devices that reduce or suppress signal interference while managing power consumption. The ability to handle one or more of these needs supports improved signal reproducibility, operating compact communications equipment, with high data rates and / or improved signal fidelity.

(Outline of the invention) The invention according to the present invention supports compensation for signal interference such as EMI or crosstalk that occurs between two or more communication channels or between two or more communication elements in a communication device. Compensating for interference can improve signal quality and increase communication bandwidth or the ability to transmit information.

In one aspect of the invention, the method or device is used to calm, suppress, reduce, cancel, or otherwise process active noise cancellation. Applicable. Active noise cancellation can include simulating, mimicking, or emulating unwanted interference, which is the actual interference that is the invader signal that continues to affect the victim signal. Generates an emulated signal that resembles. Subtracting the emulated signal from the victim signal has the consequence of canceling or negating the emulated and actual interference with each other. In other words, the noise canceler can handle the interference by creating similar interference and typically applying such simulated interference by subtraction to the signal or channel affected by the actual interference. .. Generating emulated interference and / or applying emulated interference to a victim signal can be done with one or more similar signal parameters corresponding to the actual interference signal and of the emulated interference. Matching one or more signal parameters. A device, device, operation or method through an interference canceling device that produces emulated interference is called an emulation channel.

The interference canceling device can control, search, adjust, and optimize various parameters of the embroidery channel. Various parameters include gain, amplification, phase, delay, filtering variables, carrier frequency, pole zero arrangement, and the like. Interference cancelers change one or more of these parameters within a method that seeks to minimize the energy of residual interference that remains on the victim signal after cancellation, or to control some properties. Let me. In addition, the interference canceling device comprises several circuits that update or dynamically adjust the emulation parameters from the feedback loop, or feedback, or based on the monitoring of the victim signal. Dynamic tuning can provide suppression of interference within the communication device, during operating environment, invader signals, or compensation by some other operating factor or state variation. A control circuit that performs dynamic adjustment has at least two modes of operation. In the first mode, the control circuit adjusts the first signal parameters such as amplitude or gain. In the second mode, the control circuit adjusts the second signal parameters such as phase or delay.

The discussion of interference cancellation presented in this disclosure is intended as an example. Various aspects of the invention are clearly understood or recognized by review of the detailed description set forth below of the disclosed embodiments, and by reference to the drawings, and by the appended claims.

Moreover, other aspects, devices, methods, features, effects and objectives of the invention will become apparent upon examination of the drawings and detailed description below by those skilled in the art. All aspects, devices, methods, features, effects and purposes are intended to be included in this description, to be within the scope of the invention, and to be protected by any accompanying claims. It was.

Many aspects of the invention must be better understood by the drawings described above. Each part of the drawing does not need to be drawn to scale, but instead emphasizes clearly showing the principles of the embodiments of the present invention. Further, in the drawings, the reference numbers indicate that they correspond, but the parts of the different drawings do not have to be exactly the same.

The present invention supports compensation for signal interference such as electromagnetic interference (EMI) or crosstalk that occurs between two or more communication channels or two or more communication elements of a communication device. Interference compensation improves signal quality or enhances communication bandwidth or information transmission capability. Communication channels are conductive lines, printed circuit board (PCB) patterns, flexible circuit patterns, conductors, waveguides, buses, communication antennas, media that provide signal paths, or filters, oscillators, diodes, voltage controlled oscillators. It has active or passive elements such as (VCO), PLL (Phase Synchronous Loop), amplifier, digital or mixed signal integrated circuit. In this way, channels are global system for mobile communications (GSM) devices, processors, detectors, sources, diodes, inducers, integrated circuits, to name just a few viable means. It has circuits, connectors, circuit patterns, or digital signal processing (DSP) chips.

Further, embodiments of the present invention cancel, correct, and process communication interference, EMI, or crosstalk associated with one or more communication paths of a communication system, such as a mobile radio or a high-speed digital data communication system in a mobile phone. Or support compensation. The interference sensor detects a signal representation or a sample of the interference signal or a communication signal or an interference signal that imposes interference. The interference sensor may be integrated into a structure such as a flexible cable or circuit board that supports or comprises at least one conductor that imposes or receives interference. In one embodiment, the interferometer is assigned to an invader conductor, a victim conductor, or a conductor or circuit pattern near the EMI field associated with EMI. The interference sensor is connected to the interference compensation circuit. The interference compensation circuit has at least two modes of operation. In the first mode, the interference compensation circuit actively generates or outputs a correction signal. In the second mode, the interference compensation circuit can withhold the generation or output of the signal correction signal, thereby saving power and unintentionally increasing the signal-to-noise ratio (SN ratio) contained in the communication signal. You can avoid losing to.

In one embodiment of the invention, the interference sensors are located close to one or both channels. From this position, the interference sensor extracts, guides, generates, and detects a sample or representation of the interference or invader signal that would otherwise occur. The interference sensor has a sensing or sampling channel to obtain a sample. Since the invader channel transmits a communication signal that produces interference on the victim signal, such as digital data or analog information, the sensing channel can sample the invader communication signal and / or interference. The sensing channel is, for example, a conductor for obtaining a representation of an invader signal or interference. Such sensing conductors are near the conductors that carry the invader signal, or near the conductors that carry the victim signal, or in the EM field associated with the invader channel and / or the victim channel. The sensing conductor is physically separated from the invader conductor, while being connected to the invader conductor through inductive, magnetic, electrical, and / or EM fields. That is, the sensing conductor does not need to be physically connected or in direct contact with, for example, the invader conductor, and a sample of the invader signal can be obtained.

In one embodiment of the invention, a circuit that cancels, corrects, or compensates for communication interference, or otherwise processes, has at least two modes of operation. The interference compensation circuit is connected to the sensor, for example. In the first mode, an interference compensating circuit can generate, generate, or provide a signal that, when applied to a communication signal, reduces the interference associated with such a communication signal. In the second mode, the interference compensation circuit can stop the generation or output of the interference compensation signal. The second mode can also be considered as a standby, idle, passive, sleep or power saving mode. Operating the interference compensation circuit in the second mode can provide a reduced level of power consumption.

In one embodiment of the invention, the interfering method or device EMI by matching the amplitude, phase or delay of the emulated invader signal to the actual invader signal inflicted by the victim. Can be canceled. The method of interference compensation is based on an analog control loop that minimizes the energy of the matched residual or canceled invader signal. In other words, the gain and phase compensation of the emulation path is adjusted to minimize the energy of the invader signal remaining after the cancellation of the invader signal.

Instead of processing emulation parameters to reduce the energy of the interfering signal, the parameters are adjusted based on the data rate or bit error rate. Such a data rate or bit rate is, for example, the data rate or bit rate of the received victim signal. In one embodiment, the parameters are controlled in relation to signal integrity or reception strength. For example, the value of the reception status display bar of the mobile phone is provided for control feedback.

In one embodiment, an inter-integrated circuit (I2C) bus or a serial peripheral interface (SPI) bus can be adapted to a cancel device. Therefore, the emulation parameters vary based on the information transmitted through the inter-integrated circuit (I2C) bus or serial peripheral interface (SPI).

The gain and phase of the emulation channel are two parameters controlled by the cancel device. The emulation channel also controls delay or other emulation filter parameters. The control loop operates to minimize the energy of the remaining invaders after cancellation. Other parameters controlled by the emulation channel are emulation filter parameters such as delay and center frequency or pole-zero location.

In one embodiment of the invention, the high impedance tap can directly monitor victim channels that are susceptible to unwanted interference. Therefore, the tap can provide feedback to the interference canceling device, or from there, to the control. In one embodiment, a single set of high frequency components supports more than one signal sample operation. Such dual use is advantageous in that the offset between the plurality of sets of high frequency components and the plurality of sampling points is eliminated. Utilizing a single high frequency path significantly reduces power consumption. In one embodiment, the resizable method can control gain, phase, and other emulation channel parameters as needed.

When each of the drawings shown in FIGS. 1 to 20 is described, the same parts in each drawing are numbered the same, and details of one embodiment of the present invention are described. Referring to FIG. 1, this figure shows an interference phenomenon in a mobile telephone device 100 in which a GSM high frequency receiver is invaded by one or more EMI sources. In particular, FIG. 1 shows two EMI sources 110 and 120, each emitting interference 150. One EMI source is the high-speed bus 120, which transmits data from the DSP chip 135 to the high-resolution display 140. The other EMI source is the high-speed bus 110 that transmits the data from the camera image sensor 145 to the DSP chip 135. The camera image sensor 145 comprises a charge-coupled device (CCD) camera element or a complementary metal oxide semiconductor (CMOS) camera element.

It is often desired to increase the data rate or bandwidth of each path, conductor or display channel and camera buses 110 and 120. This desire is motivated by the need to impose an increase in the amount of information processing over a period of time, which corresponds to an increase in the number of pixels, and to support higher display / camera resolutions. This demand is motivated by the demand to reduce the number of data paths in buses 110 and 120. Thereby, the data rate of the remaining routes is increased to support the current total amount of information per fixed time. Therefore, improvements in the display 140 or camera device 145 (eg, higher resolution or centralized communication bus) reduce the capabilities of the high frequency receiver 105 in the mobile phone device 100.

In addition, improved reception of low power or noise signals provides other incentives to reduce or otherwise handle interference 150 or crosstalk. A weak high frequency signal has, for example, less intensity than the noise level of EMI150. Therefore, it is desired to reduce the EMI 150 in order to facilitate the reception of weaker high frequency signals or to enable the operation of mobile phones or other communication devices in a noisy environment.

The communication device 100 includes a form interference compensation or correction circuit 130, which is depicted as a specific example of the integrated circuit 130. The interference compensation circuit 130 transmits an interference compensation signal in or on a channel that is the receiver of the interference to cancel, mitigate, or otherwise compensate for the received interference. The interference compensation signal is either transmitted to another channel or is derived from or generated from a sample of the invader communication signal that is being generated with interference or crosstalk.

The interference compensation circuit 130 is coupled between the sources 110 and 120 of the interference 150 and the victim device 105 that is damaged by the interference 150. In this configuration, the interference compensation circuit 130 can sample or receive a portion of the signal that causes the interference. The interference compensation circuit 130 also produces an interference correction signal that applies to the victim signal affected by the unwanted interference 150. In other words, the interference compensation circuit 130 connects to the channels 110, 120 that are producing the interference 150, and also generates an interference compensation signal, and interferes with the interference compensation signal in order to further perform interference cancellation, compensation, or correction. Applies to Recipient 105 (Victim Device).

Batteries not shown in FIG. 1 typically supply energy or power to the interference compensation circuit 130 in the same way as the other circuits of device 100. As an alternative to batteries, fuel cells or other portable or small energy sources can supply electricity to the device 100. In the more detailed discussion below, the device 100 and in particular the interference compensation circuit 130 are operated by a method of managing battery drain.

The interference compensation circuit 130 can generate an interference compensation signal via a model of the interference result. The model can estimate, approximate, emulate, or imitate an interference signal to generate an interference compensation signal in the form of a signal. The interference compensation signal has a waveform and shape that match the actual interference signal. Settings or adjustments that adjust the model, such as modeling parameters, are defined by the characteristics of this waveform.

The interference compensation circuit 130 receives a signal representative of the invader signal (or its own interference) from sensors 115, 125 adjacent to one or both of the data buses 110, 120 that generate EMI. In one embodiment, sensors 115, 125 have conductors associated with one or both of the data bus channels 110, 120. Sensors 115, 125 are devoted to obtaining a sample of the invader signal. For example, the data bus 110 detects, finds, or samples a plurality of conductors that transmit data between the camera 145 and the DSP chip 135, and the invader signal, or at least one other conductor, or data for direct reception. Instead of transmission, it has a combined EM or EMI field. In addition, one of the data bus conductors acts as a sensor during the time interval, while the particular conductor is not meaningful transmission data.

In one embodiment, the sensors 115, 125 are integrated into a common configuration to which the conductors of the data buses 110, 120 are attached or added. For example, sensors 115, 125 are added to or part of a flexible cable. In one embodiment, sensors 115, 125 include a conductive pattern placed on a flexible cable. In one embodiment, sensors 115, 125 are coupled to communication signals propagating to data buses 110, 120 through the EM field of those signals. For example, binding is via induction rather than through direct connection. Therefore, the sensors 115 and 125 are separated from the invader channel below the threshold frequency and connected to the invader channel above the threshold frequency. Further, the sensors 115 and 125 are separated from the invader channel below the threshold voltage and connected to the invader channel above the threshold voltage.

In one embodiment of the present invention, the sensors 115 and 125 include interference collectors that are placed very close to the interference source. In another embodiment of the invention, the interference compensation circuit 130 extracts an interference signal from a conductor close to the victim antenna. In yet another embodiment of the invention, the interference sensors 115, 125 include a sampling mechanism embedded as a lane in the bus path of the interference source. For example, the sampling mechanism has additional conductor wires that run parallel to other data lines in a flexible cable or in a fixed circuit board. By embedding a sampling mechanism, good results can be obtained (excellent) sampling mechanism and effective attributes for EMI cancellers or interference cancellers / compensators: compact size, flexible design, modularization, signal Consistency and the minimum power withdrawal from the detected line can be provided.

Embedding or integrating sensors 115, 125, or unifying, unifying sampling mechanisms, or an integrated configuration with bus paths 110, 120 can be an interference source, or some, with sensors 115, 125. The distance to the interference source of is very close. The resulting extreme proximity facilitates strong sampling of interference associated with high frequency signals.

Embedding or integrating sensors 115, 125 into bus paths 110, 120 gives system designers, especially printed circuit board designers, design flexibility. For example, design engineers are freed from the constraint of placing the sampling mechanism in the circuit board space near the interference source, which is required for antenna mounting. System designers are freed from the task of antenna design for one or more specific reception requirements, such as field patterns and frequency ranges.

The sensor solution, integrated or embedded, based on devoting conductors 115 and 125 of multiple conductor buses 110 and 120 to detection, is an inherent ability (inherent ability) to receive EMI interference. ) Is demonstrated. The inherent ability reflects the inherent radiative properties of other conductors that generate interference. In other words, radiation and reception are generally complementary phenomena, so it is the unique reception of the desired EMI frequency that constitutes the sensing conductor to have a form similar to the radiation conductor (invader). Is to provide.

In one embodiment of the invention, the embedded interferometers 115, 125 can extend to the entire length of the data buses 110, 120 having data lines that advance, extend, or radiate invader EMI. it can.

In one embodiment of the invention, the interference detection conductor 115 can extend a limited portion of the total length of the data buses 110, 120, whereby the data buses 110, 120 maintain a compact width. To help. Another embodiment that can minimize the width of the data bus has a sampling mechanism that crosses or underlies data lines 110, 120. Crossing is orthogonal crossing. The detection conductor and the data conductor form, for example, an obtuse angle or an acute angle.

The detection conductors 115, 125, shown in FIG. 1, are arranged at the terminal ends of the data buses 110, 120. For example, the detection conductor 115 includes a conductor between the DSP chip 135 and the flexible cable with the data bus 110. Such conductors can extend above, below and / or around the bus, for example as conductor bands.

In one embodiment of the invention, the embedded interference sensor 115 not only receives EMI interference from key elements such as the associated data bus 110, but also such as the display 140, camera 145, DSP 135, etc. EMI interference is also received from other sources on the handset. Therefore, the single sensor 115 provides support for correcting interference from more than one source of interference through such a single sensor. That is, the single sensor 115 can sample multiple sources of interference to support correction of interference from two or more sources through the single sensor and the interference compensation circuit 130 connected to it.

In one embodiment of the invention, the interference compensation circuit 130 samples its interference signal (eg, an invader source) from conduction elements 115, 125 that receive radiation EMI 150. This sampling approach is non-interrupting and can sense EMI150 (or filtered EMI) or invader signals. In particular, the invader data line / source remains physically in its original state. Data buses 110, 120 can function with little or no power loss for sensors 115, 123 connected through inductive or capacitive coupling, eg, without physical or direct electrical contact. That is, the inducible material can separate the detection conductors 115, 125 from the invader conductor during inductive, capacitive or EM bonding.

After sampling the reference signal, the interference compensation circuit 130 provides a compensation or cancellation signal whose magnitude, phase, and delay have been adjusted so that the interference compensation circuit 130 cancels most of the interference signal connected to the victim signal. Generate. That is, the reference signal with the sample is filtered and processed to become a negative interference signal incurred by the received victim signal. The magnitude, phase and delay adjustment parameters are indefinite and are controlled to optimize the cancel capability.

See also Figure 2. FIG. 2 shows some flexible cables 200 having data buses 110 and 120 inside a mobile telephone or other electronic communication device according to an embodiment of the present invention. High-speed buses such as the data buses 110 and 120 that generate EMI take multiple forms, such as specific examples of flexible cables. Such flexible cables are also typically referred to as flexible circuits, flat cables, or ribbon cables. Flexible cables are embedded, laminated, or printed, with multiple conductor wires or channels (typically copper wires), or flexible molding structures such as plastic or polymer films, or some other induction product. Alternatively, it is provided with an insulating material.

In one embodiment, the detectors 115, 125 include a conductor wire fixed onto the flexible cable 200. The detectors 115 and 125 are formed in or integrally with the flexible cable 200 as a step in the manufacturing process, including, for example, lithography, when the flexible cable 200 is manufactured. The flexible cable 200 may instead be applied in a later step, for example by attaching a sensor to the flexible cable 200. That is, the detectors 115 and 125 may be attached to the conventional flexible cable supplied by the vendor.

See also Figure 3. FIG. 3 shows a functional block diagram of the interference compensation circuit 130 according to the embodiment of the present invention. The interference compensation circuit 130 shown in FIG. 3 is embodied in the chip shape as an integrated circuit (IC) shown in FIG. 1 or as a hybrid circuit. Alternatively, the interference compensation circuit 130 may include separate components mounted or mounted on a circuit board or similar board. Further, in one embodiment of the present invention, the device 100 shown in FIG. 1 includes the device 300 of FIG.

The interference compensation circuit 130 draws or obtains power or energy from a power source 360 connected to the battery 365. As described in more detail below, the interference compensation circuit 130 operates in multiple modes with different levels of battery energy consumption.

FIG. 3 shows a typical interference compensation circuit 130 including a variable phase regulator 305, a variable gain amplifier (VGB) 310, an emulated filter 315, a variable delay regulator 320, an adder node 325, a power detector 330 and a controller 335. It is a functional block diagram.

The interference sensor (EMI sampler) 115 obtains a sample of the invader signal, for example, by coupling to an interference field. The sampled interference signal is first fed to the variable phase adjuster 305 through the compensation circuit 130. The phase adjuster matches the phase of the emulated interference signal with the phase of the interference signal connected to the victim antenna 340 at the addition node 325. That is, since the phase adjuster 305 adjusts the phase of the compensation signal with reference to the phase of interference, the compensation signal can cancel or reduce the interference when subtracted from other phases. Cancellation occurs by subtracting the signal coupled on the victim antenna 340 from the emulated signal generated by the interference compensation circuit 130 using the interference signal sampled by the sensor 115 at the addition node 325.

In another embodiment of the compensation circuit 130, the phase adjuster 305 can adjust the phase of the emulated signal to be 180 ° out of phase with the interfering coupled signal. In this case, the addition node 325 adds rather than subtracts the two signals.

In one embodiment, the phase adjuster 305 includes variable resistors, inducers, and capacitances for bias, pull-up and signal conditioning, as well as orthogonal hybrids and fourth silicon superstep junction variable capacitance diodes. Be prepared. In another embodiment, the phase adjuster (phase shifter) 305 has an active circuit.

The optional emulation filter 315 can follow the variable phase adjuster 305 within the cancellation path. The emulation filter 315 is typically a bandpass (BP) filter that forms a channel coupling and is adjustable to compensate for any drift within the channel carrier frequency.

In one embodiment, the emulation filter 315 includes a centralized element and a variable capacitance diode. The variable capacitance diode helps to change or control the carrier frequency of the embroidery channel.

In one embodiment, the emulation filter 315 is a Finite Impulse Response (FIR) filter. FIR filters include taps and tap intervals inferred or determined from the coupling channel characteristics. In order to have strong cancellation for the improved signal matching of the communication device 100, the emulation filter 315 should typically match the coupled channels as a whole within the desired frequency band.

The next stage of the cancellation path is the controllable delay regulator 320, which provides matching between the group delay of the coupled signal through the victim antenna 340 and the group delay of the emulated compensation signal at the add node 325.

The output of the delay regulator 320 is supplied to the variable gain amplifier (VGA) 310. The VGA 310 matches the amplification degree of the signal emulated by the addition node 325 with the amplification degree of the interference signal. Given that the emulation filter 315 models the frequency characteristics of the coupled channel (ie, the attenuation of frequencies for other frequencies), the VGA 310 provides a certain amount of gain throughout the desired frequency band. Therefore, the emulation filters 315 and VGA 310 work together to match the magnitude of the response on the absolute scale of channel coupling rather than simply on the associated scale.

The VGA 310 supplies the interference compensation signal to the adder node 325. The addition node 325 then applies the interference signal to the victim channel to cancel, cancel, attenuate, or suppress the interference.

In one embodiment, the addition node 325 comprises a directional coupler. In another embodiment, the adder node 325 comprises an active circuit such as an analog adder, which is typically a three-terminal element, or an output buffer, which is typically a two-terminal element.

For best performance, add node 325 should effectively introduce inconsistencies in the victim antenna signal path. That is, the addition node 325 should ideally maintain the inherent impedance of device 130. Nevertheless, in some situations, small or controlled levels of impedance mismatch are acceptable. Avoiding impedance mismatches means that the add node 325 should be on the tap and have high output impedance. In addition, add-on node 325 does not inflict significant loss on the victim antenna receive path. Such losses adversely affect the sensitivity of the receiver. For the sake of explanation, this impedance matching consideration refers to a device with an intrinsic impedance of 50Ω. However, embodiments of the present invention apply to systems of essentially any intrinsic impedance.

The parts 305, 310, 315 and 320 shown in FIG. 3 are in a unique order, but the order is a concrete example and should not be considered limited. Moreover, the order of those parts 305, 310, 315 and 320 is usually not important and is changed during the maintenance of satisfactory performance of the interference compensation circuit 130, or parts 305, 310, 315 and 320 are re-used. Arranged.

The interference compensation circuit 130, illustrated as an EMI canceller, is flexible in terms of cancellation or compensation parameters that are tuned or controlled to optimize the matching of the emulated coupling channel to the actual EMI coupling channel. I will provide a. More specifically, the controller 335 and the power detector 330 connected to it provide a feedback loop for dynamically adjusting circuit elements in a way that provides strong compensation for interference. Consideration of the embodiment of the interference compensation circuit 130 continues in connection with FIGS. 8 to 20 below.

Move to Figure 4. FIG. 4 shows a frequency plot 420 of the spectral content of the interference signal according to the interference compensation according to the embodiment of the present invention, which is superimposed on the frequency plot 410 of the spectral content of the interference signal before the interference compensation. There is. That is, Graph 400 shows experimental test data collected before and after the application of interference compensation for embodiments of the present invention.

More specifically, FIG. 4 shows the coupling channel characteristics between the flexible cable shown in FIG. 2 and the flexible cable of the 2.11 GHz antenna, similar to the above discussion. In the experiment, the test data show that the embodiment of the interference compensation circuit 130 was able to achieve signal reduction greater than 25 dB in the frequency band 2.1 GHz to 2.15 GHz.

Move to Fig. 5 and Fig. 6. These figures show frequency plots 500 and 600 before and after application of the interference compensation according to the embodiment of the present invention, respectively. More specifically, traces 520 and 600 of these plots 500 show data obtained from experiments with interference compensators according to embodiments of the present invention.

Spectrums 520 and 620 characterize a 450 megabit per second (Mbps) (PRBS-31) interfering signal coupled to a 2.1 GHz antenna that is in close proximity to a flexible cable carrying a 450 Mbps signal. In the frequency band of region 510, the compensation was able to achieve interference suppression of approximately 12 dB.

Here, reference to FIGS. 1, 2 and 3 together, the interference compensation circuit 130 functions or operates in at least two modes. In one mode, circuit 130 can consume less power than in the other mode. That is, the interference compensation circuit 130 can transition from the active mode using relatively high power to the mode using relatively low power. The low power mode can be referred to as a standby mode, a power saving mode, a passive mode, an idle mode, a sleep mode, or an off mode. In low power mode, the interference compensation circuit derives a reduced power level, minimal power, virtually no power, or no power at all. Some or all of the interference compensation circuits shown in FIG. 3 in part or in whole and some or all of the above considerations are disconnected from the power in low power mode. The presence of one or more criteria causes a transition from active mode to standby mode. Therefore, the transition occurs automatically in response to an event, in a manner different from the user turning off a device with circuit 130, such as a mobile phone.

In the use of the handset, operating the interference compensation circuit 130 in the power saving mode can extend the operation time with one battery charge, thus emphasizing the commercial appeal of the handset. Power saving can be implemented or achieved without degrading the quality of the interference compensation capability.

Inside the wireless handset device, a situation arises that can provide an opportunity to reduce power consumption. In particular, many EMI sources are not always active and therefore do not always emit interference. The interference compensation circuit 130 and its associated controller 335 may transition to sleep mode or standby mode to reduce power consumption in situations where it is not necessary to provide an interference signal. That is, power is removed from a selected set of those elements or circuit elements rather than having one or more circuit elements that receive power while not producing output or actively processing the signal.

Therefore, in one embodiment of the invention, the device 100 experiences a situation in which it is not necessary to operate a particular component of the interference compensation circuit 130. In such a state, the controller 335 puts those components in low power or standby mode, or removes all power from those components. For example, if the EMI source is not active for the total threshold time, the interference compensation circuit 130 transitions to standby mode. More specifically, when the bus 110 is not actively communicating data, the interference compensation circuit 130 switches to standby mode to save battery power.

In one embodiment, the sensor 115 provides a signal indicating whether the bus 110 is active or not. That is, the sensor 115 can provide a level, voltage, amplitude or signal strength that indicates whether the invader signal is being actively transmitted.

When appropriate, power is removed from the components 305, 310, 315 and 320 that generate the emulated EMI signal. In addition, power is additionally or selectively removed from some or all of the control circuits 335. However, the components used to preserve the emulation characteristics or characteristics, i.e. the emulation channel set for setting the alignment with the coupling channel , are in their recent state when the EMI source (eg, invader channel 110) is restarted. It is actively held to restore the emulation channel of the interference compensation circuit immediately or quickly. In other words, the storage device of controller 335 holds power access to avoid loss of parameter values stored in memory. Retaining the value of the parameter in memory facilitates a quick return to activate cancellation on resumption of the EMI source. Therefore, returning the operating settings of the phase adjuster 305, emulation filter 315, delay adjuster 320 and VGA 310 interferes if the emulation is retrained from any reset state following the transition from standby mode to active mode. Avoid happening.

Operating in standby mode means powering down all of one or more circuit components and / or operating in a state of reduced power use. In several stages, the latter is preferred because it allows the component to quickly reach outside the standby range when the EMI source is restarted.

In one embodiment of the present invention, the standby signal provides an instruction or an opportunity to transition the interference compensation circuit to a power saving or standby state. The standby signal also triggers power saving or a transition from the standby state to the active state. The element transmitting the EMI source, or the associated power detector, can generate a signal indicating that the data is actively transmitted. For example, a DSP chip 135 that sends data to the display of a mobile telephone device 100 can output a binary signal or code to indicate that the signal is inevitably an emission of EMI rather than transmission data.

As another embodiment, the camera imaging sensor 145, which sends the data to the DSP chip, can output a binary signal or digital code to indicate whether the signal is transmission data that produces EMI. As yet another embodiment, a high frequency device using time division multiplexing can provide a triggering standby signal. Such high frequency devices are used, for example, in the field of GSM or wideband code division multiple access (W-CDMA). In such a state, the wireless communication device outputs a binary signal characterizing that it is time-division or interval transmission data. During those dual communication parts, the transmitted signal attacks the second high frequency device of the radio handset, so interference compensation is activated.

In one embodiment of the invention, a power detector, such as detector 330, which is not connected to the output of the sampler, inspects the sampled EMI signal and waits based on the nature of the sampled EMI signal. Generate a signal. For example, the standby state is set when the detector 330 determines that the sampled EMI signal is given or falls below a predetermined threshold. Conversely, the interference compensation circuit 130 is activated when the detected power exceeds the threshold value.

In one embodiment of the invention, a standby state is declared when the local time peak amplitude of the sampled EMI signal is below a given threshold. One advantage of this embodiment is that it generally does not require extra pins in the device package to supply a dedicated standby signal. Instead, the standby signal is drawn from a valid pin that is already in use for EMI cancellation.

In one embodiment, the transition between standby mode and active mode occurs in response to changes in the strength of the received signal. For example, the circuit becomes active when the number of receive bars on a mobile phone reaches a threshold level. In other embodiments, transitions occur, for example, in response to changes in data rate or bit rate.

In one embodiment of the invention, all components 305, 310, 315, 320 of the emulation channel used to generate an emulated EMI signal from an EMI source signal sampled by a sensor are on low power standby. Put in a state. In one embodiment of the invention, one or more of the following components are placed in standby mode in response to the occurrence of a standby state. The one or more components are a phase regulator 305, a bandpass (BP) channel emulation filter 315, a delay regulator 320 and a VGA 310. The reduction in power consumption of those device components 305, 310, 315, 320 facilitates significant power savings when the EMI source is not active.

The controller 335, also referred to as the control module, is deactivated when the EMI source is inactive. In the absence of an EMI source and the controller 335 is inactive, interference is typically not an issue. More specifically, if EMI does not occur, the emulation path produces a zero emulation signal. In many situations, the increased interference capability is the result of deactivating the emulation path when the EMI source is inactive. If the emulation channel remains active when the EMI source is inactive, the emulation channel parameters drift for a set of numbers that are poorly matched to the underlying EMI coupled channel. In this state, activating the EMI source will result in a simple tuning that allows the interference compensation circuit 130 to learn new and more effective parameters. In other words, the improperly tuned coupled channel will continue to produce a zero emulation signal, since the sampled EMI source signal will be zero when the interference compensation circuit 130 is inactive.

In one embodiment of the invention, all components of the control module, or substantially all of the active components, are placed in a standby state when the standby signal is activated, thereby providing a high power saving level. Ru.

In another embodiment of the invention, while the rest of the control module 335 is inactive, a register or memory element is used to accumulate controllable parameters when the emulation channel is fully powered. .. This embodiment facilitates the quick or immediate return of the embroidery channel to the pre-standby state when the device is in standby mode. In other words, once the system leaves standby mode, the interference compensation circuit 130 can restart cancellation from a well-known and accurate channel mode in advance, rather than starting cancellation from any reset state. Resuming operation of the interference compensation circuit 130 from any parameter set may require an undesired long time interval prior to converging on an accurate channel model. The execution of EMI cancellation during this learning time is inadequate or ineligible.

Next, move to Fig. 7. FIG. 7 shows a flowchart of the process 700 that operates the interference compensation circuit 130 in a plurality of modes according to an embodiment of the present invention. This process 700, which is referred to as an interference compensation circuit processing operation, is considered as a process for power consumption management of the interference compensation circuit 130.

At step 705, a data transmitter, such as camera 145 or DSP chip 135, issues a standby signal consisting of a digital code. The digital code signals the state of the transmitter, for example, whether the transmission is actively transmitting data or is in a passive state for two time periods of data transmission. In one embodiment, the code clearly indicates whether the transmitter is actively transmitting data or preparing to change between operating states.

At step 710, the controller 335 receives the standby signal and further determines whether the data transmitter is in the active or passive state of transmitting data. In determination step 715, if the standby signal indicates that the transmitter is active, the flow of process 700 is branched to step 725. On the other hand, if the standby signal indicates that the transmitter is passive, determination step 720 follows determination step 715.

In determination step 720, controller 335 determines whether the interference compensation circuit 130 is in active mode or otherwise in passive mode. If the interference compensation circuit 130 is in active mode, step 730 follows step 720.

In step 730, controller 335 stores the latest or current compensation parameters in memory and further removes power from the emulation channel components 305, 310, 315 and 320. This operation puts the interference compensation circuit 130 in standby or power saving mode. The stored compensation parameters typically include the settings of the adjustable parts 305, 310, 315 and 320 of the emulation channel.

If in determination step 720 the controller 335 determines that the interference compensation circuit 130 is in standby mode rather than in active mode, step 740 follows step 720. At step 740, the interference compensation circuit 130 remains in standby mode.

In decision step 715, if the process flow branches to step 725 instead of step 720 (based on a standby signal indicating active data transmission), in step 725 the controller 335 has the interference compensation circuit 130 in active mode. Or determine if it is in standby mode.

If the interference compensation circuit 130 is in active mode, step 745 follows step 725. At step 745, the interference compensation circuit 130 remains in active mode.

If the controller 335 determines in determination step 725 that the interference compensation circuit 130 is in standby mode instead of active mode, step 735 continues in step 725. At step 735, controller 335 reads the latest or last used interference parameter from memory and returns power to the depowered component. Reverting power typically involves initializing the adjustable parts 305, 310, 315 and 320 of the emulation channel with parameter settings recalled from memory.

Step 750 follows the execution of either step 735 or 745. At step 750, the interference compensation circuit 130 generates an interference estimate based on the processing of the invader sample obtained by the sensor 115. According to the above discussion with reference to FIG. 3, the emulation channel components 305, 310, 315 and 320 process the sample to output the interference estimate.

In step 755, the interference compensation circuit 130 applies an interference estimate to the victim channel to cancel, suppress, or compensate for the interference that has occurred in the victim channel.

Following the execution of any of steps 730, 740 and 755, process 700 returns to the starting point described above and performs step 705. Execution of process 700 continues the next loop iteration.

Next, refer to FIG. FIG. 8 shows a functional block diagram of the EMI compensation circuit 130A according to the embodiment of the present invention. The illustrated circuit 130A is an embodiment of the system 130 described above.

As shown, the tap of the invader signal 850 is supplied to the emulation channel 810 that affects the invader signal to mimic the invader signal supplied to the victim signal. In feeding the victim signal, the invader signal may cause, for example, one or more phase shifts, amplitude losses, and frequency selective coupling. The 315, 310, and 305 stages within the emulation channel represent these combined effects. Thus, steps 315, 310, 305 process the signal from the invader tap 850 to produce a signal that matches the invader signal coupled to the victim signal.

To generate the emulated interference signal, the emulation channel 810 includes mechanisms such as the primary emulation filter 315, VGA 310 and variable phase adjuster 305. In the illustrated embodiment, the primary emulation filter 315 is a fixed filter that acts as a coarse scale model of the coupled channel. Channel modeling is then reduced by variable gain 310 and phase adjustment 305 steps to finely tune the match to the actual coupled channel. The emulated coupled signal generated by emulation channel 810 is then subtracted from the damaged victim signal at add node 325. If the parameters of emulation channel 810 are set appropriately, the generated emulated invader signal is essentially equal to the actual invader signal received by the victim signal. Therefore, after the addition node 325, the invader signal is substantially removed from the victim signal.

The phase control stage 335A is an analog control signal α._ΦThe amount of phase adjustment in the phase adjuster 305 is determined by generating (alpha subphi). This control signal is supplied to the phase adjuster 305 and directly determines the phase adjustment amount applied to the emulation channel.

Similarly, the gain control stage 335B is an analog control signal α._gThe gain adjustment amount of VGA310 is set by generating (α subg). This control signal is supplied to VGA10 and directly identifies the gain adjustment amount applied to the emulation channel.

Next, refer to FIG. FIG. 9 represents the functional block diagram of one embodiment of the phase control stage 335A shown in FIG. 8 described above. Here, phase control step 335A receives the emulated invader signal from emulation channel 810 and further samples the affected victim signal. Current value of phase Φ₀Along with the phase adjuster 305 using (Physab 0), the phase control stage 335A has a new value α for the phase adjuster 305._ΦProcess those received signals to produce (alpha subphi).

The emulated invader signal is separated into a pair of emulated invader signals with additional phase adjustment or time delay applied. Δ_Φ1The phase of (Delta Subphi One) is added to the first signal of the pair separated through the phase shifter (or delay) 910A, thereby Φ.₀+ Δ_Φ1Provides an output signal that represents an emulation signal with a total phase adjustment of. Similarly, Φ₀+ Δ_Φ2To provide an output signal that represents an emulation signal with total phase adjustment of_Φ2The phase of (Delta Subfight) is added to the second signal of the pair separated through the phase shifter 910B.

Like the input emulation signal, the harmed victim signal is also separated into the first and second affected victim signals. Addition node 920A is Φ₀+ Δ_Φ1Using the phase adjustment of, the invader subtracts the first signal of the victim signal separation pair from the output of the first phase shifter 910A to result in the canceled victim signal. Addition node 920B is Φ₀+ Δ_Φ2Using the phase adjustment of, the invader subtracts the second signal of the victim signal separation pair from the output of the second phase shifter 910b in order to result in the canceled victim signal.

The energy of each victim signal canceled by the invader is then obtained by utilizing the power detection devices 930A, 930B followed by the lowpass filters (LPF) 940A, 940B for each signal.

The output of LPF940A and 940B is Δ_Φ1And Δ_Φ2Special phase adjustment (Φ applied to embroidery channel₀Represents the energy of the victim signal in which the invader was canceled, with (exceeding the phase of). Due to the advantages of this disclosure for each victim signal whose invaders have been canceled by one of ordinary skill in the art, the victim signal whose invader component has been canceled is (i) energy plus the victim signal only (ii) canceled. It is correctly understood that it is equal to the sum of the energy of the invader component. This analysis is valid because the invader and victim signals are statistically independent signals. The energy analysis characteristics are appropriate because the subtracting element 950 subtracts a pair of signals for the victim signal in which the invader signal is canceled.

Since both victim signals for which the invader signal has been canceled share the same victim component, the energy contributions of the victim signal can be negated with each other at the output of the subtraction node 950. In other words, it corresponds to zero or no victim signal. Thus, the output of the subtraction node 950 is Δ_Φ1Cancel invader signal with special phase and Δ_Φ2The difference in energy between the cancel invader signal and the cancel invader signal with the special phase of. In other words, the output of the subtraction node 950 corresponds to the mathematical derivative of the invader energy residue with respect to the phase. In particular, it (output) has a phase value of Φ.₀+ (Δ_Φ1+ Δ_Φ2) / 2 Approximate to a negative derivative.

The output of the subtraction node 950 is transmitted to the integrating device 960, and the integrated output is the value Φ of the phase adjuster 305.₀Value α for direct control of_ΦWhen used as, the system converges to a state where the output of the subtraction node 950 becomes 0 or approaches 0. This condition corresponds to minimizing the energy left over by the invaders with respect to phase adjustment, thus obtaining optimal control values.

Next, refer to FIG. FIG. 10 shows a functional block diagram of the embodiment of the gain control stage shown in FIG. The operation of this control stage is somewhat similar to that of the phase control stage. Gain control stage 335B receives emulated invader signals and harmed victim signals from emulation channel 810 as inputs. The gain provided by VGA310 without emulation channel 810 is shown as A0 (A subzero).

The emulated signal is separated into a pair of emulated invader signals to which additional gain or attenuation is provided. Additional gain 1 + Δ_gIs A₀+ A₀Δ_gThe first signal of the separated pair is fed through the amplifier 1010A to provide an output signal that represents the emulated signal with the total gain of. Similarly, gain 1-Δ_gIs A₀-A₀Δ_gThe second signal of the separated pair is fed through the amplifier 1010B to provide an output signal that represents the emulated signal with the total gain of. Gain element 1-Δ_gIs generally less than 1, so the result of amplifier 1010B may be interpreted as attenuation.

The harmed victim signal is also separated into a first and second harmed victim signal, like the input emulation signal. Addition node 1020A A from the first signal of an isolated pair of harmed victim signals₀+ A₀Δ_gUsing the gain of, the invader subtracts the output of the first amplifier 1010A to achieve the canceled victim signal. Addition node 1020B A from the second signal of the isolated pair of harmed victim signals₀-A₀Δ_gUsing the gain of, the invader subtracts the output of the second amplifier 1010B to achieve the canceled victim signal.

The energy of each victim signal with the invader component canceled is then obtained by utilizing the power detection devices 1030A, 1030B followed by the low pass filters (LPF) 1040A, 1040B corresponding to each signal. The output of LPF1040A and 1040B is 1 + Δ_gAnd 1-Δ_gSpecial gain (A applied to embroidery channel)₀Represents the energy of the victim signal in which the invader was canceled, with (exceeding the gain of). The subtraction device 1050 subtracts a pair of energy signals for the victim signal with the invader component canceled. The output of the subtraction node 1050 is 1 + Δ_gCancel invader signal with special gain of 1-Δ_gThe difference in energy between the cancel invader signal and the cancel invader signal with the special gain of. In other words, the output of the subtraction node 1050 corresponds to the mathematical derivative of the invader energy residue with respect to the gain. In particular, it (output) has a gain value of A₀Approximates to a negative derivative based on.

The output of the subtraction node 1050 is transmitted to the integrating device 1060, and the integrated output is the value A of VGA310.₀Value α for direct control of_gWhen used as, the system converges to a state where the output of the subtraction node 1050 is at or near 0. This condition corresponds to substantially minimizing the energy left over by the invaders with respect to gain adjustment. Therefore, a substantially optimum control value is obtained.

Next, refer to FIG. FIG. 11 shows a functional block diagram of the phase and gain control module integrated within the signal control module 335 for the EMI compensation device 130B according to an embodiment of the present invention. The system 130B is an example of embodying the system 130 of FIG. 3 described above.

As shown in FIGS. 9 and 10 and described above, it is certain that the phase control module 335A and the gain control module 335B in those figures are replica circuit components. However, the otherwise redundant components of the system 130B provide gain control and phase control functionality, thereby creating more compact or efficient circuits.

The advantages of removing the excess part of the circuit are low power consumption, reduced parasitic effects, and reduced size of the circuit. That is, a useful circuit is realized by integrating the phase and gain control module with the signal control module in the EMI canceling device 130B. The coalescing module 335C receives a third input (in addition to the affected victim signal and the emulated aggression signal) to select the mode of operation. In other words, the module 335 is characterized as a controller with two modes of operation: gain control on the one hand and phase control on the other.

The mode selector signal acts as a switch that controls whether the module 335C should adjust the gain or phase of the emulation channel 810 at any given time. The control module 335C has a gain control signal α_gAnd phase control signal α_ΦBoth are output. In one mode, the control module 335C adjusts the gain while keeping the phase constant. In the other mode, the control module 335C adjusts the phase while keeping the gain constant. In the embodiment of the deformation, the gain and the phase may be adjusted at the same time. FIG. 12, described below, shows an embodiment of the combined control module 335C.

Next, refer to FIG. FIG. 12 shows a functional block diagram of the combined gain and phase control module 335C. The combined gain and phase control module 335C has some functional similarities to the phase control module 335A and the gain control module. One feature is the five switches 1210A-1210E of the gain control module 335B that control whether it is the gain or the phase that is tuned.

When the mode selection signal input to the control module 335C specifies gain adjustment, the five switches 1210A-1210E are configured as shown in Figure 12. In particular, switches 1210A and 1210C are configured such that the first tuning path adds gain through amplifier 1010A slightly beyond emulation channel 810. Switches 1210B and 1210D, on the other hand, are set so that the second tuning path passes through amplifier 1010A slightly beyond emulation channel 810 to reduce gain. In addition, switch 1210E is set so that the output of the derivative is fed to the integrator 1060 for gain control. With these settings, the control module 335C operates in the same manner as the gain control module described above.

When the mode selection signal input to the control module 335C specifies phase adjustment, all five switches 1210A-1210E are switched to the opposite state shown in FIG. In particular, switches 1210A and 1210C are configured such that the first tuning path passes through the phase regulator 910A slightly beyond the emulation channel 810 to add a first phase or corresponding delay offset. In addition, switches 1210B and 1210D are configured so that the second adjustment path adds a second phase offset through the phase shifter 910B just beyond the emulation channel 810. In addition, switch 1210E is configured so that the output of the derivative is fed to the product branch 960 for phase control. With these settings, the control module 335C operates in the same manner as the phase control module described above.

The mode selection signal to the control module 335C can be obtained by various methods. For example, a clock signal is used as a model selection signal that periodically alternates between gain and phase adjustment for a fixed period. Other options may use the derivative signal output from the adder node 950. For example, when the derivative value falls below a preset threshold, it indicates that the current adjustment mode has reached the optimum value, and the mode selection signal switches the operation mode to either one. This is done as a basis for the gain and phase adjustment to remain substantially optimally constant.

In this way, the control module 335C can switch between several operating modes in response to the occurrence of a time event, signal event, or state or state event. Further, the switching occurs automatically or based on operating rules, signal changes, feedback, signal analysis results, signal excesses or matches for predetermined thresholds, or operating conditions. More specifically, mode changes occur based on the time of circulation or the indicated time or the indicated time interval.

In one embodiment, the transition between control modes occurs in response to changes in the strength of the received signal. For example, the mode change occurs when the numerical value of the reception bar of the mobile phone reaches a certain threshold level. In one embodiment, the transition occurs, for example, in response to changes in the data rate or bit rate.

Next, refer to FIG. FIG. 13 is a diagram showing an interference compensation circuit 1300 connected to the interference sensors 115 and 125 according to an embodiment of the present invention. In other words, in one embodiment, the system 100 shown in FIG. 1 and described above comprises circuit 1300 instead of circuit 130. A specific example of this consists of a high impedance tap 1310 of the victim signal 1305 corrected by the noise cancel adder 1380.

Circuit 1300 comprises, for example, a power detector 1320, which is a root mean square (RMS) detector or peak power detector. The power detector 1320 is followed by a switch 1330 that selects at least two samples and one of the hold circuits 1340A, 1340B. The sample and hold circuits 1340A and 1340B are connected to the comparator or multi-stage comparator 1350. The output of the comparator 1350 goes to the control and timing circuit 1360. The control and timing circuit 1360 provides timing to the switch 1330, sample and hold circuits 1340, comparator 1350 and other control circuits required. The control and timing circuit 1360 also controls the emulation channel 810 of the active radio canceller. The emulation channel 810 acts on the tap or sample of the invader signal 850 in an attempt to mimic the invader signal coupled to the victim signal as described above.

The interference compensation circuit 1300 can operate in one of two or more modes, which exhibits reduced power consumption as compared to the other. In other words, in one embodiment of the present invention, the circuit 1300 transitions to the power saving mode by the occurrence of a triggering event. In that mode, power is removed from one or more power detectors 1320, switching devices 1330, sample and hold circuits 1340A and 1340B, and comparator 1350. The power detector 1320 and the comparator 1350 are two major factors in power consumption, so cutting off their power supply is fully successful in saving power. The control and timing circuit 1360 usually comprises a low speed digital logic circuit that consumes a small amount of power. Nevertheless, this circuit 1360 is largely inactive, with the exception of the register holding the parameters of emulation channel 810.

Next, refer to FIG. FIG. 14 shows a logical flow diagram of a process for optimizing emulation channel parameters according to an embodiment of the present invention. The control and timing circuits perform gradient optimization of emulation channel parameters and further adjust the timing of all control loop circuits. At step 1410, emulation filter parameters, such as gain and phase, are individually or simultaneously subjected to a small amount of perturbation (disturbance). At step 1420 the effects of noise fluctuations are evaluated and at step 1430 decisions are made regarding the direction of travel. Then, the process is continuously repeated. In this way, the interference compensation parameters are applied to handle changes in the operating environment, thereby maintaining a sufficient level of interference compensation.

Next, refer to FIG. FIG. 15 is a diagram showing a control and timing circuit related to an embodiment of the present invention. The comparison results are supplied to the decision state machine 1500. The decision state machine 1500 then controls a plurality of up / down counters 1520 that control a plurality of digital-to-analog converters (DACs) 1530. The plurality of DAC1530s then control the gain, phase and other parameters of the emulation filter as much as possible. The timing circuit 1510 adjusts the timing of the decision state machine with other control loop circuits.

The system 1360 in Figure 15 is generally resizable to control variables for emulation channel parameters. The gain and phase of the emulation channel are specific parameters to be controlled. Other parameters controlled are emulation filter parameters such as delay and center frequency or pole zero location.

See Figure 16. FIG. 16 shows an interference compensation circuit 1600 with a filter 1610 in front of the power detector 1320. The filter 1610 in front of the power detector 1320 is used to remove or partially remove the received signal while effectively passing the invader signal. The control loop is then more sensitive to the cancellation of the invader signal and can also provide a significant reduction in the invader signal that is not worthy of the received signal. FIG. 16 also provides an embodiment that provides the respective connections between the multistage comparator 1350 and the multistage sample and hold circuit 1340.

Next, refer to FIG. FIG. 17 shows an interference compensation circuit 1700 with a downconverter and an intermediate frequency (IF) filter 1720 in front of the power detector 1320. The IF filter 1720 has a response as shown in Figure 18 that removes the down-converted victim signal, but passes through the remnants of the invader noise. The advantage of this example of detecting invader residues is that the small band of the removed victim signal is higher than that of the example shown in Figure 16, which makes it easier to implement a filter. I will provide a. In many situations, the overall result is more responsive to invader residues beyond the victim signal in control loop optimization. If the victim signal detected by the power detector is higher than the invader residue, the control loop normally does not respond to the invader residue. A higher reduction in the invader signal is achieved when the victim signal response is eliminated before the power detector in the control loop.

Next, refer to FIG. FIG. 18 shows the frequency response 1800 of the IF filter 1720 shown in FIG. 17 for one embodiment of the invention.

Next, refer to FIG. FIG. 19 shows interference compensation in which the affected victim signal and the tapped invader signal 850 are down-converted by the down converter 1910 and the down converter 1930, respectively, in the intermediate frequency band before the cancel adder 1380. The circuit 1900 is shown. The advantage of this embodiment is that the emulation channel 810 and control loop 1980 operate at the IF frequency instead of the RF frequency. In addition, the victim signal 1950 does not need to be further down-converted by the receiver. Finally, the filter 1720 in front of the control loop power detector 1320 has a higher slight bandwidth for the victim signal. Its bandwidth reduces the victim signal beyond the remnants of the invader signal, which is easier to perform with the actual filter.

Next, refer to FIG. FIG. 20 shows an interference compensation circuit 2000 with a downconverter 2010 already present in a communication device. Here, tap 1310 is turned off after down conversion to baseband frequency, thus avoiding any extra mixing circuitry (and associated power consumption).

In summary, the system according to an embodiment of the present invention includes a sensor that detects a typical interference sample or an interference signal sample, an emulation channel that processes the sample interference signal to generate an interference compensation signal, and an emulation channel. It includes a control loop to control. A system according to an embodiment of the present invention includes circuits that operate in two or more modes for canceling, correcting, or compensating for interference inflicted on a communication signal by a variant or further signal. This system is applicable to wireless communication devices such as mobile phones, wireless base stations, personal digital assistants (PDAs), satellite or cable television components, computers, radar systems, wireless networks and the like.

One of ordinary skill in the art should understand that the present invention is not limited to the fields described herein, and that the embodiments described herein are for illustration purposes only and are not restrictive. .. Furthermore, it should be understood that various alternatives from the embodiments of the invention described herein will be found by examination of the specification and accompanying drawings by those skilled in the art. Such embodiments are available by practicing the present invention. As described above, the scope of application of the present invention is intended to be limited only to the scope of claims in the attached sheet.

<figref num="1">It is a functional block diagram which shows the communication system which includes the interference sensor connected to the interference compensation circuit which concerns on one Embodiment of this invention.</figref><figref num="2">It is a figure which shows the flexible circuit which includes the interference compensation circuit which concerns on one Embodiment of this invention.</figref><figref num="3">It is a functional block diagram of the interference compensation circuit which concerns on one Embodiment of this invention.</figref><figref num="4">It is a characteristic diagram which showed the spectral coupling of the interference signal before compensating the spectral coupling of the interference signal corrected by the interference compensation circuit which concerns on one Embodiment of this invention in a graph, and then superimposed and graphed.</figref><figref num="5">It is a characteristic diagram which graph | showed the spectral energy of the interference signal before application of the interference compensation which concerns on one Embodiment of this invention.</figref><figref num="6">It is a characteristic diagram which graph | showed the spectral energy of the interference signal according to the application of the interference compensation which concerns on one Embodiment of this invention.</figref><figref num="7">It is a flowchart for the process which operates the interference compensation circuit of a plurality of modes which concerns on one Embodiment of this invention.</figref><figref num="8">It is a functional block diagram of the EMI compensation control circuit which concerns on one Embodiment of this invention.</figref><figref num="9">It is a functional block diagram of the phase control stage of the interference compensation circuit which concerns on one Embodiment of this invention.</figref><figref num="10">It is a functional block diagram of the gain control stage of the interference compensation circuit which concerns on one Embodiment of this invention.</figref><figref num="11">FIG. 5 is a functional block diagram of an EMI interference control circuit having a coupled gain and phase control circuit according to an embodiment of the present invention.</figref><figref num="12">It is a functional block diagram of the coupled gain and phase control stage which concerns on one Embodiment of this invention.</figref><figref num="13">It is a circuit diagram which shows the interference compensation control circuit which concerns on one Embodiment of this invention.</figref><figref num="14">It is a flow diagram which shows the process for optimizing the emulation channel parameter which concerns on one Embodiment of this invention.</figref><figref num="15">It is a functional block diagram of the control and timing circuit which concerns on one Embodiment of this invention.</figref><figref num="16">It is a circuit diagram which shows the interference correction circuit which includes the power detector which has the filtered input which concerns on one Embodiment of this invention.</figref><figref num="17">It is a circuit diagram which shows the interference compensation circuit which comprises the down converter and the intermediate frequency (IF) filter connected to the power detector which concerns on one Embodiment of this invention.</figref><figref num="18">It is a characteristic diagram which graphed the frequency response of the specific IF filter which concerns on one Embodiment of this invention.</figref><figref num="19">It is a circuit diagram which shows the interference compensation circuit which down-converts both the damaged victim signal and the tapped invader signal to the IF band prior to cancellation, according to one embodiment of the present invention.</figref><figref num="20">It is a circuit diagram which shows the interference compensation circuit which uses the down converter before the receiver which concerns on one Embodiment of this invention.</figref>