Transmitting information in mobile communications system

Transmission information in mobile communication system

The present invention relates to the transmission of information in a mobile communication system.

Figure 1 illustrates the network structure of E-UMTS as an example. The E-UMTS is a system evolved from the existing UMTS system.

The basic specifications of the E-UMTS system are currently being developed by the Third Generation Partnership Project (3GPP). The E-UMTS system can be called a Long Term Evolution (LTE) system.

As shown in Figure 1, an E-UMTS network can be composed of an E-UTRAN and a core network (CN). E-UTRAN may include User Equipment (UE), a base station called eNodeB or eNB, and an Access Gate (AG) located at the end of the network and connected to the external network.

The AG can be divided into a part for processing user traffic and a part for processing control traffic. The part of AG for processing user traffic and the part of AG for processing control traffic can be connected to each other via a new interface for communication.

One or more cells can exist in an eNodeB (eNB), and the eNodeB can be connected via an interface for transmitting user traffic and/or controlling traffic.

CN may also include AG and a node suitable for user registration of UE. An interface can also be provided in E-UMTS to distinguish E-UTRAN and CN.

The radio interface protocol layer between a mobile terminal and a network can be divided into a first layer (L11) according to the three lower layers of the well-known Open System Interconnection (OSI) model in communication systems , A second layer (L2), and a third layer (L3). The physical layer of the first layer uses a physical channel to provide information transmission. A radio resource control (Radio Resource Cpntrol, RRC) layer located in the third layer controls the radio resources between the mobile terminal and the network.

The RRC layer allows the exchange of RRC messages between the mobile terminal and the network. The RRC layer can be located in each network node, such as eNodeB, AG, or located in the eNodeB or the AG.

Figure 2 shows the structure of the radio interface protocol between a terminal and a UMTS Terrestrial Radio Access Network (UTRAN) based on the 3GPP radio access network specifications. The radio interface protocol in Figure 2 is composed of a physical layer, a data link layer, and a network layer horizontally, and is composed of a user plane for transmitting data information and a control plane for transmitting control signals Composed vertically.

The protocol layers in Figure 2 can be divided into a first layer (L1), a second layer (L2), and a third layer according to the three lower layers of the well-known Open System Interconnection (OSI) model in the communication system. Three layers (L3). The radio protocol layers in the control plane shown in Figure 2 and the radio protocol layers in the user plane shown in Figure 3 will now be explained.

A physical layer (which is the first layer) uses a physical channel to provide information transmission services to an upper layer. The physical layer is connected to a media access control (MAC) layer (located on the upper layer) via a transmission channel.

Data is transferred between the MAC layer and the physical layer via a transmission channel. Data is also transferred between different physical layers (specifically, between a physical layer on a transmitting side and a physical layer on a receiving side).

The MAC layer, one of the second layers, provides services to the Radio Link Control (RLC) layer (which is the upper layer of the MAC layer) via a logical channel. The RLC layer of the second layer supports reliable data transmission.

The function performed by the RLC can be implemented as a functional block in the MAC layer. However, the RLC layer may not exist.

The second layer of the Packet Data Convergence Protocol (PDCP) layer is used to efficiently transmit data using IP packets (such as IPv4 or IPv6) over a radio interface with a small bandwidth. The PDCP layer uses a function for this purpose (called header compression) to reduce unnecessary control information.

A radio resource control (RRC) layer at the bottom of the third layer is only defined in the control plane. The RRC layer processes the transmission channels and physical channels used for the configuration, reconfiguration, and release of radio bears (RB). A radio bearer (RB) refers to the service provided by the second layer for data transfer between mobile terminals and UTRAN.

The downlink transmission channel used to transmit data from the network to the mobile terminal can include a broadcast channel (BCH) for transmitting system information, and a downlink shared channel for transmitting user traffic or control information (SCH). Downlink multicast and broadcast service traffic or control messages can be transmitted via the downlink SCH, or via a separate downlink multicast channel (MCH). Used to transmit data from the mobile terminal to the network uplink transmission channel, which may include a random access channel (Random Access Channel, RACH) used to transmit an initial control message, and used to transmit a user flow or control The uplink shared channel (SCH) of the message.

A random access channel (RACH) will be explained in detail below. Generally speaking, when a terminal matches time synchronization with a network, or the terminal transmits corresponding data through the uplink, if there is no uplink radio resource to transmit the data, the RACH is used to obtain the radio resource.

For example, when a terminal is turned on, the terminal substantially matches the downlink synchronization so that it can receive system information from a cell that it wishes to access. The terminal should transmit the access request to the network or base station for RRC connection after receiving the system information. However, if the terminal does not currently synchronize the network with time synchronization and has not acquired an uplink radio resource, RACH is used.

In other words, the terminal uses RACH to request a radio resource from the network for transmitting an access request message. The base station then allocates an appropriate radio resource to the terminal to allow the terminal to transmit an RRC connection message. The terminal can then use the allocated radio resources to transmit the RRC connection message to the network.

In another example, when the terminal forms an RRC connection with the network, the terminal obtains a radio resource from the network according to the radio resource schedule, and uses the allocated radio resource to transmit data to the network. However, if no data remains in the terminal buffer, the network may not allocate uplink radio resources, because it is inefficient to allocate an uplink radio resource to a terminal that has no data to transmit. The status of the terminal buffer is reported to the network periodically or according to events. If new data that does not require a radio resource is generated in the buffer, the terminal uses RACH because it does not currently have uplink radio resources allocated. In other words, the terminal uses RACH to request a radio resource required for data transmission from the network.

In the following, the RACH in Wideband Code Division Multiple Access (WCDMA) will be explained. The RACH channel is used to transmit data with a short length through the uplink.

Some RRC messages, such as an RRC connection request message, cell update message, or URA update message, can be transmitted on RACH. A logical channel Common Control Channel (CCCH), Dedicated Control Channel (DCCH) and Dedicated Traffic Channel (DTCH) are mapped to RACH, and RACH is mapped to a physical channel entity random Access channel (Physical Random Access Channel, PRACH).

When the terminal MAC instructs a PRACH to be transmitted to a physical layer of a terminal, the physical layer of the terminal selects an access slot and a signature to transmit the PRACH preamble to the physical layer of the terminal via the uplink. This preamble is used for transmission with an access slot interval of 1.33 milliseconds. One of the sixteen signatures is selected and transmitted up to a certain length of the first initial part of one of the access slots.

After the terminal transmits the preceding text, the base station uses a downlink physical channel to acquire an indicator channel (Acquisition Indicator Channel, AICH) to transmit a response signal. In response to the AICH transmission transmitted in the preceding paragraph, the signature selected by the preceding paragraph reaches a certain length of the access slot corresponding to the initial part of the transmitted access slot.

The base station uses the signature transmitted from the AICH to transmit a positive response (ACK) or negative response (NACK) to the terminal. When receiving the ACK signal, the terminal uses an OVSF code corresponding to the transmitted signal to transmit a message part with a length of 10 milliseconds or 20 milliseconds. When receiving the NACK, the terminal MAC instructs to transmit PRACH again to the physical layer of the terminal after an appropriate period of time. If the terminal does not receive the AICH corresponding to the previous transmission preamble, the terminal transmits a new preamble after a designated access slot using a higher level of power than the previous preamble.

The Channel Quality Indicator (CQI) information enables a terminal to measure the status of the downlink channel in the current cell and provides information about the measurement status to the base station. The base station then uses the provided CQI information to perform radio resource scheduling. For example, if the value of CQI may be between 1 and 10, then 1 indicates that the channel is not in a good state, and 10 indicates that the channel is in a good state.

When the terminal transmits the CQI information of 10 to the base station, the base station can determine that the current downlink channel is in a good state, and transmit the data to the terminal according to a higher bit rate. Conversely, when the terminal transmits 1 CQI information to the base station, the base station can determine that the downlink channel is not in a good state, and transmit the data to the terminal according to a lower bit rate. The base informs the terminal in advance, that is, the terminal should periodically or according to the occurrence of an event report to transmit CQI information.

The inventor recognizes at least the following problems in the existing RACH program. As previously indicated, when using RACH, the terminal first selects a signature and an access slot, and then transmits a preamble on the uplink. Afterwards, when receiving the ACK from the base station, the terminal transmits a part of the message to the base station in response to the preceding text. Therefore, the terminal must perform preamble transmission, ACK reception, and partial message transmission to notify the base station using RACH specific information in the related technical method. As a result, delay time is increased and radio resources are wasted. Based on the recognition of this problem, the various features and aspects described herein have been conceived by the inventors.

One aspect of this disclosure is to provide a method for transmitting information in a mobile communication system, which avoids unnecessary consumption of wireless resources and reduces the delay time of information transmission.

In one aspect, a method for allocating radio resources in a mobile communication system is provided. The method includes receiving packet information about a signature and occasion used to access a random access channel (RACH), selecting a signature and a random access channel (RACH) timing based on the packet information, and selecting a random access channel (RACH) timing based on the selected information. The signature and RACH timing transmit a preamble, receive a message including the radio resources allocated according to the selected signature and RACH timing, and use the allocated radio resources to transmit data.

The present invention covers the grouping of RACH signatures and timing according to predetermined criteria. It also covers that the predetermined standard includes at least one of the purpose of using RACH, CQI information, request amount of radio resources, and a reason for establishment.

The present invention has covered one of the purposes of using RACH including an initial access, delivery, maintaining synchronization, an access release, and a radio resource request. It further covers the establishment reason including one of an emergency call, a transition from an idle state to an active state, and a transition from an interrupted state to an active state. The packet information can be received as one of system information and a paging message.

In another aspect of this disclosure, a method for allocating a radio resource in a mobile communication system is provided. The method includes transmitting packet information about a signature and timing used to access a random access channel (RACH), receiving a preamble transmitted based on a signature selected based on the packet information and RACH timing, and transmitting a packet based on the timing. Select the signature and the message of the radio resource allocated by the RACH timing, and receive the data transmitted using the allocated radio resource.

The present invention also covers a method of grouping RACH signatures and timings according to predetermined standards. It also covers that the predetermined standard includes at least one of a purpose for using RACH, CQI information, request amount of radio resources, and a reason for establishment.

The present invention has covered one of the purposes of using RACH including an initial access, delivery, maintaining synchronization, an access release, and a radio resource request. It further covers the establishment reason including one of an emergency call, a transition from an idle state to an active state, and a transition from an interrupted state to an active state.

The present invention has covered that the packet information is transmitted as one of system information and a paging message. It also covers that the packet information is transmitted as one of system information and a paging message. The method may further include changing and retransmitting the packet information.

In another aspect of this disclosure, a method for allocating radio resources in a mobile communication system is provided. The method includes a network transmission of packet information, which is related to the signature and timing for accessing a random access channel (RACH); a mobile communication terminal, which selects a signature and a random access channel (RACH) based on the packet information. ) Timing, the mobile communication terminal transmits a preceding text based on the selected signature and RACH timing, the network transmits a message including radio resources allocated based on the selected signature and RACH timing, and the mobile communication terminal uses the allocated radio Resource transfer information.

The present invention covers the grouping of RACH signatures and timing according to predetermined criteria. It also covers that the predetermined standard includes at least one of a purpose of using RACH, CQI information, request amount of radio resources, and a reason for establishment.

The present invention covers the purpose of using RACH including one of an initial access, delivery, maintaining synchronization, an access release, and a radio resource request. It further covers the establishment reason including one of an emergency call, a transition from an idle state to an active state, and a transition from an interrupted state to an active state.

The present invention has covered the network to transmit the packet information by one of system information and a paging message. It also covers the method and also includes changing and retransmitting the network of the packet information.

The foregoing and other features and aspects of this disclosure will be better understood from the following detailed description with reference to the accompanying drawings.

The following description will propose additional features and advantages of the present invention, and part of them will be understood from the description, or can be learned by implementing the features in this disclosure. It should be understood that the above general description and the following detailed description are exemplary and explanatory, and are intended to provide further explanation of the scope of patent application.

Those skilled in the art will also be able to easily understand these and other exemplary embodiments from the following detailed description with reference to the accompanying drawings. The features of this document are not limited to any specific embodiments disclosed.

A detailed description will now be provided with reference to the drawings. The features in this article can be implemented in mobile communication systems (such as UMTS). However, these features can be applied to other communication systems operating in accordance with other specifications.

This disclosure proposes a method by which a terminal uses a RACH preamble signature and transmission time point, or certain information of the transmission timing to notify a base station, so as to reduce the delay time before transmitting data, and effectively use the uplink radio resource. To achieve this, the features described here classify signatures and transmission timing based on specific information for use.

In a specific embodiment, these features are implemented so that the transmission of a preceding text can be based on a signature group and a RACH resource group classified according to a number of specific information, from the signatures grouped according to the first information, and according to the second Select a signature and a resource in the transmission timing of the information packet. The specific information may include information on the purpose of use of RACH, CQI information, information on the amount of requested radio resources, and information on the reasons for the establishment.

For example, the purpose of use of RACH may include initial access, delivery, synchronization maintenance, an access release, and a radio resource request of a terminal. CQI information refers to the value of the status of the downlink channel. The amount of radio resource request refers to the buffer status of the terminal, which can be indicated by 50 bits, 100 bits, or 200 bits. The establishment cause can refer to an emergency call, the terminal changes from an idle state to an active state, or the terminal changes from an interrupted or detached state to an active state.

The RACH resource can indicate a RACH opportunity. Specifically, the RACH resource indication is notified by the base station to a terminal in a cell that uses RACH resource information.

The resource information is allocated with a specific frequency and a specific time. The resource information may also include the duration of the RACH opportunity.

In another specific embodiment, the implementation of these features enables the transmission of a preceding text to select a signature from the group by a combination of self-signature and RACH timing and a configuration of the combination, and by using the first information The signature of the packet, and the transmission timing of the packet based on the second information. In an exemplary embodiment, a signature always has the same meaning, such as information. However, a signature can have another meaning according to its combined transmission timing in this embodiment.

An explanation of a method for selecting a signature and a resource based on the signature of the first information packet and the transmission timing of the second information packet to transmit the foregoing will now be provided.

<u style="single">Signature selection</u>

A base station groups all signatures according to a specific purpose. The information about the packet signature is transmitted to a terminal using system information or a paging message. Therefore, when using RACH, the terminal selects a signature group from signature groups classified according to specific information about the terminal state. Once a signature has been selected, the terminal randomly selects a signature from the corresponding signature group.

For example, if there are 64 signatures, the numbers 0 to 63 will be set to those signatures. The base station uses the purpose of use of RACH as one of the specific information used for grouping. A first group can be configured for initial access, a second group can be configured for delivery, a third group can be configured for synchronization maintenance, and a fourth group can be configured for access release And a fifth group can be configured for the purpose of radio resource request. The base station appropriately maps the integral signature to each group.

In other words, the first group has signatures from 0 to 11, the second group has signatures from 12 to 23, the third group has signatures from 24 to 35, and the fourth group has signatures from 36 to 47. 5 groups have signatures from 48 to 63. The information about the signature of the group based on the purpose of use of RACH (or group information) is transmitted to the terminal using system information or paging message. Therefore, if the purpose of RACH is to submit, the terminal selects the second group according to the set group, and then randomly selects one of the signatures mapped to the second group and has a number from 12 to 23.

In addition, the base station can dynamically change packet information. In other words, if a terminal in a cell often uses one of the signature groups, the base station can map more signatures to the corresponding group.

For example, if the 4th group has 12 signatures and the 5th group has 16 signatures, if the usage frequency of the terminals in the 4th group is low and the 5th group is higher in the cell, the base station can reduce the number of signatures in the 4th group And increase the number of signatures in the fifth group. The change information about the signature group is transmitted from the base station to the terminal using system information or a paging message.

<u style="single">RACH timing</u>

As shown in Figure 4, the base station groups the overall RACH occasions according to a specific purpose. The specific purpose may be the same as or different from the specific information previously disclosed as the grouping standard for signatures.

For example, the signature can be grouped according to the purpose of use of RACH, and the RACH timing can be grouped according to the CQI information, or both the signature and the RACH timing can be grouped according to the purpose of use of the RACH. The packet information about the packetized RACH timing is transmitted to the terminal using system information or paging messages.

Therefore, when the terminal uses RACH, a group is selected from the group of RACH occasions according to the state of the terminal. If the selected group includes two or more RACH occasions, the terminal randomly selects a RACH occasion from the selected group.

The base station uses CQI information as specific information for grouping RACH occasions. For example, the base station will have a group A with a bad channel state, a group B with a good channel state, and a group C with a best channel state. The base station appropriately maps the RACH timing to each group.

Information about grouping based on CQI information is transmitted to the terminal using system information or paging messages. If the terminal is in a bad channel state, the terminal selects group A according to the set grouping information. If the group A includes two or more RACH occasions, the terminal randomly selects a RACH occasion.

The base station can also dynamically change the group information. The packet information changed by the base station in each cycle of the RACH timing or each multiple of the cycle is transmitted to the terminal using system information or a paging message.

Now, a method of selecting one of the groups configured by the combination of signature and RACH timing to transmit a preceding paragraph will be explained. In this method, a specific signature may not always have the same information. For example, the same signature can transmit different information according to the RACH timing of its combination.

Figure 5 shows how a base station combines signatures and RACH timing for its grouping. Figure 6 shows the actual grouping based on the combination of the establishment reason and CQI information described in Figure 5.

As shown in Figure 5, there are four RACH opportunities A, B, C, and D in one cycle. The four RACH opportunities can exist at the same time as shown in Figure 5, or they can exist separately at different times. For example, four RACH occasions A, B, C, and D may exist at time 2, or at times 4, 5, and 6 alone. The total number of signatures is assumed to be 16.

The reason for establishment and CQI information are used as the grouping standard. The establishment reason and CQI information are used in the two situations respectively. The four groups use the reason for establishment and the generation of CQI information as shown in Figure 6. If the establishment reason of the terminal is A and the CQI value is 1, the terminal randomly selects a value from the third group including C5 to C9 and D0 to D8. C5 indicates the RACH timing of a C and the signature of 5.

As previously pointed out, a signature and a RACH timing may not always indicate the same information. For example, the signature 10 may convey different information depending on the RACH timing of its combination. A RACH opportunity A can also transmit different information based on the signature combined with it. The packet information based on the combination of signature and RACH timing is also transmitted to the terminal using system information or a paging message.

Figure 7 shows an exemplary signal flow of a method for transmitting information in a mobile communication system according to a specific embodiment. As shown in FIG. 7, the base station 20 groups the overall signature and RACH timing according to a specific purpose, and uses system information or a paging message to notify the terminal 10 of the grouping information (S10).

According to a setting of the base station 20, the terminal 10 selects a signature and a RACH opportunity from the set of signatures and RACH opportunities, or selects a group from a complex set configured by a combination of signatures and RACH opportunities (S11). Using the previous example, the terminal 10 selects a value from the third group including C5 to C9 and D0 to D8.

The terminal 10 then uses the selected signature and RACH timing to transmit a preamble to the base station 20 (S12). The base station 20 then determines which group the corresponding signature and RACH timing belong to, and schedules a radio resource according to the decision to allocate an appropriate radio resource to the terminal 10 (S13).

For example, when the terminal 10 has used a signature group as the initial access, and the RACH timing has been grouped according to the radio resource request amount of 100 bits, the base station 20 allocates an appropriate radio resource to the terminal based on the information. After receiving the allocated appropriate radio resources from the base station, the terminal uses the corresponding radio resources to transmit uplink data to the base station 20 (S14).

When the terminal uses RACH, the features described here can be implemented so that a preceding transmission is used to notify the base station of specific information, and the base station can effectively allocate a radio resource based on the specific information for data transmission to The terminal. The delay time before the terminal transmits data has been reduced, and the consumption of radio resources is avoided or at least minimized.

Because the characteristics of this disclosure can be embodied in several forms without departing from its spirit or basic characteristics, it should also be understood that the above specific embodiments are not limited to any details previously described, but should be viewed in a broad sense unless otherwise specified. It is within the scope of the scope of the attached application. Therefore, all changes and modifications that fall within the measurement and limits of the scope of the patent application, or the equivalent of these measurements and limits, are expected to be covered by the scope of the patent application.

The foregoing specific embodiments and features are merely exemplary and should not be regarded as limiting. This teaching can be easily applied to other types of equipment.

This description is intended to demonstrate and does not limit the scope of the patent application. Those who are familiar with this technology will understand many alternatives, modifications and changes. In the scope of the patent application, when the quotation function is implemented, the component plus function clause is expected to cover the structure described here, and it is not only structurally equivalent but also an equivalent structure.

<p>10. . . terminal</p><p>20. . . Base station</p>

The drawings included in this document provide further understanding, and are incorporated into and constitute a part of this specification. The drawings show various exemplary embodiments and together with descriptions are used to explain the principles of this disclosure. The features, elements, and aspects referenced by the same numbers in different figures represent the same, equivalent or similar features, elements, or aspects according to one or more specific embodiments.

Figure 1 shows an exemplary network structure of the E-UMTS of a mobile communication system.

Figure 2 shows the various layers on the control plane of the radio protocol.

Figure 3 shows the various layers on the user plane of the radio protocol.

Figure 4 shows that according to some embodiments, all RACH opportunities are grouped by the base station according to a specific purpose.

Figure 5 shows how a base station combines signatures and RACH timing for grouping according to some specific embodiments.

Figure 6 shows the grouping according to the combination of the reason for creation and the CQI information described in Figure 5.

Figure 7 shows the signal flow of a method for transmitting information in a mobile communication system according to some specific embodiments.