CN102149049B - Trunked service implementation method in digital trunking communication system and trunked user terminal - Google Patents

Abstract

A method for realizing a trunking service, the method comprising: periodically detecting a trunking user terminal; if there is scheduling information of a TPCCH channel, searching for a transport block TB containing information carried by the TPCCH channel, and performing decoding to obtain the information carried by the TPCCH channel ; The user terminal detects the PDCCH channel in each TTI, and searches for the TB of the information carried, and successfully decodes, configures and establishes a service plane channel; the calling group user terminal initiates a speech using the established service plane channel; The trunking user terminal detects the PDCCH channel within the TTI, searches for TBs containing information carried by the TTCH channel, and decodes the found TBs. The invention also discloses a cluster user terminal. After applying the embodiment of the present invention, the call establishment time can be shortened, and the resource utilization rate can be improved.

Description

Trunking service realization method and trunking user terminal in digital trunking communication system

technical field

The present invention relates to mobile communication technology, in particular to a method for realizing trunking services in a digital trunking communication system based on Time Division-Long Term Evolution (TD-LTE, Time Division-Long Term Evolution) technology and a trunking user terminal.

Background technique

Due to its unique characteristics of dispatching, group calling and fast calling, the digital trunking communication system has played a huge role in the field of professional communication. Since the mid-1990s, the digital trunking communication system has risen in the world, has been widely used, and has achieved good economic and social benefits. Existing digital trunking communication systems mainly include: Terrestrial Trunked Radio (TETRA, Terrestrial Trunked Radio) system, Integrated Digital Enhanced Networks (iDEN, Integrated Digital Enhanced Networks) system, Open Trunking Architecture (GoTa, Global Open Trunking Architecture) system and GT800 system etc.

The group call service is the most basic service provided by the digital trunking communication system. The group call service allows the trunking user terminal to establish a group call to a group of trunking user terminals belonging to a given area, using half-duplex mode; in the process of group call communication, any member of the group can become a speaker, but Only one talker is allowed at any time, that is, the calling group user terminal, and the others are all listeners, that is, the called group user terminal. The given area is called a group call area, including a cluster of cells. During call establishment, the system assigns a group call channel to each cell in the group call area, and all called trunking user terminals monitor the downlink; the called trunking user terminal can obtain the right to speak by preempting the uplink operation. In the group call service, all cluster user terminals in the same cell share a downlink and preempt the uplink, so wireless resources can be greatly saved and the spectrum utilization rate of the system can be improved.

Another basic service provided by the digital trunking communication system is broadcast call service. The only difference between the broadcast call service and the group call service is: in the broadcast call service, only the call originator can speak, and the others are all listeners. If the call originator withdraws from the call, the broadcast call will be terminated. The specific implementation processes of the broadcast call service and the group call service are basically the same, and will not be repeated here.

For a digital trunking communication system, the call setup time (the time from initiating a call to being able to speak) is an important performance indicator. This time mainly depends on the complexity of the signaling interaction between the trunking user terminal and the network side. Each network element The transmission delay between devices and the way network element devices process signaling, etc. Since the existing digital trunking communication systems are mostly implemented based on Global System for Mobile Communications (GSM, Global System for Mobile Communications) or Code Division Multiple Access (CDMA, Code Division Multiple Access) technology, base stations need to be controlled uniformly by base station controllers, and cannot communicate with the core network. Direct communication results in more signaling interactions during the establishment of trunking services such as group call services and broadcast call services, thereby prolonging the call establishment time. In addition, in the existing digital trunking communication system, trunking services are all carried in the circuit domain, so the sharing of service channels cannot be realized, resulting in a decrease in resource utilization.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a trunking service implementation method, which can shorten the call setup time and improve resource utilization.

Another object of the present invention is to provide a trunking user terminal, which can shorten call setup time and improve resource utilization.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

A method for implementing trunking services, applied in a digital trunking communication system based on time division long-term evolution TD-LTE technology,

In the system, a downlink logical channel and a downlink transmission channel for realizing trunking services are newly added, and the downlink logical channels are the trunking paging control channel TPCCH for transmitting trunking paging control information, the trunking control channel TCCH for transmitting control information, and A trunking traffic channel TTCH for transmitting data information, and the downlink transmission channel is a trunking paging transmission channel TPCH carrying the TPCCH channel;

The trunking paging control information is mapped from the TPCCH channel to the TPCH channel, and then the TPCH channel is mapped to the physical downlink shared channel PDSCH; the control information is mapped from the TCCH channel to the downlink shared channel DL-SCH, and then mapped by the DL-SCH channel To the PDSCH channel; data information is mapped from the TTCH channel to the DL-SCH channel, and then the DL-SCH channel is mapped to the physical downlink shared channel PDSCH;

Respectively load the scheduling information of the TPCCH channel, TCCH channel and TTCH channel on the PDCCH with their respective identifiers;

Each cluster user terminal periodically detects the physical downlink control channel PDCCH, searches for the transport block TB carried on the PDSCH channel according to the scheduling information of the found TPCCH channel, and decodes the TB to obtain the TPCCH channel information carried;

According to the information carried by the TPCCH channel, each trunking user terminal judges whether itself belongs to a user terminal in the currently initiated trunking call, and if so, establishes a control plane channel of the trunking call;

In the control plane channel, the user terminal detects the PDCCH channel in each transmission time interval TTI, and when detecting the scheduling information of the TCCH channel, searches for the information carried on the PDSCH channel according to the scheduling information of the TCCH channel. TB, and successfully decode the TB carried on the PDSCH channel, configure and establish a service plane channel;

The calling group user terminal uses the established service plane channel to initiate a speech;

The called trunking user terminal detects the PDCCH channel within the TTI, and when it detects the scheduling information carrying the TTCH channel, searches for the TB carried on the PDSCH channel according to the scheduling information of the TTCH channel, and searches for the TB carried on the PDSCH channel The TB on the channel is decoded to obtain the transmission data information.

The identifier of the TPCCH channel is the temporary trunking paging radio network identifier TP-RNTI; the identifier of the TCCH channel and the identifier of the TTCH channel are the temporary trunking service radio network identifier G-RNTI.

The identifier of the TPCCH channel is the temporary trunked paging radio network identifier TP-RNTI; in the air interface layer 2 protocol, the identifier of the TCCH channel and the identifier of the TTCH channel are different logical channel numbers LCID.

The establishment of the control plane channel includes: establishment of TCCH channel-related entities and contexts, and the TCCH channel-related entities include: packet data convergence protocol PDCP entity, radio link control protocol RLC entity, media access control layer MAC entity and physical layer PHY entity.

After searching for the TB carried on the PDSCH channel according to the scheduling information of the TTCH channel, and decoding the found TB, it further includes:

Detecting the PDCCH channel, searching for TBs carried on the PDSCH channel according to the detected scheduling information of the TTCH channel, and decoding the TBs carried on the PDSCH channel to obtain transmission data information.

The method further includes:

After the speaking right of the calling group user terminal is preempted, all called group user terminals re-detect the PDCCH channel in each TTI, and when it is detected that the scheduling information of the TTCH channel is carried on the PDCCH channel, Searching for TBs carried on the PDSCH channel according to the scheduling information of the TTCH channel, and decoding the TBs carried on the PDSCH channel to obtain transmission data information;

After that, the PDCCH channel is detected, and according to the detected scheduling information of the TTCH channel, the TB carried on the PDSCH channel is searched, and the TB carried on the PDSCH channel is decoded to obtain transmission data information.

Before each cluster user terminal periodically detects the PDCCH channel, it further includes:

The base station notifies each cluster user terminal of the sending opportunity and the sending period of the TPCCH channel through a broadcast message; the sending opportunity is the sending location information of the TPCCH channel.

The sending position information is the radio frame and subframe information used for sending the TPCCH channel; the subframe is a P0 subframe.

A trunking user terminal, applied in a digital trunking communication system based on time-division long-term evolution TD-LTE technology,

In the system, a downlink logical channel and a downlink transmission channel for realizing trunking services are newly added, and the downlink logical channels are the trunking paging control channel TPCCH for transmitting trunking paging control information, the trunking control channel TCCH for transmitting control information, and A trunking traffic channel TTCH for transmitting data information, and the downlink transmission channel is a trunking paging transmission channel TPCH carrying the TPCCH channel;

The trunking paging control information is mapped from the TPCCH channel to the TPCH channel, and then the TPCH channel is mapped to the physical downlink shared channel PDSCH; the control information is mapped from the TCCH channel to the downlink shared channel DL-SCH, and then mapped by the DL-SCH channel To the PDSCH channel; data information is mapped from the TTCH channel to the DL-SCH channel, and then the DL-SCH channel is mapped to the physical downlink shared channel PDSCH;

The cluster user terminal includes:

The detection unit is configured to periodically detect the physical downlink control channel PDCCH, and if the PDCCH carries the scheduling information of the TPCCH channel, search for the transmission carried on the PDSCH channel according to the scheduling information of the TPCCH channel block TB, and decode the TB on the PDSCH channel, obtain the information carried by the TPCCH channel, and establish the control plane channel of the trunking call; in the control plane channel, detect the PDCCH in each transmission time interval TTI channel, and when it is detected that the scheduling information of the TCCH channel is carried on the PDCCH channel, the TB carried on the PDSCH channel is searched according to the scheduling information of the TCCH channel, and the TB carried on the PDSCH channel is successfully decoded, configured and Establish business plane channel;

The judging unit is configured to judge whether the cluster user terminal is the calling cluster user terminal or the called cluster user terminal according to the obtained information, and notify the execution unit of the judgment result;

The execution unit is configured to use the established service plane channel to initiate a speech when the cluster user terminal where it is located is the calling cluster user terminal;

When the cluster user terminal where it is located is the called cluster user terminal, detect the PDCCH channel in each TTI, and when it is detected that the scheduling information of the TTCH channel is carried on the PDCCH channel, according to the scheduling information of the TTCH channel Searching for TBs carried on the PDSCH channel, and decoding the TBs carried on the PDSCH channel to obtain transmission data information.

The identifier of the TPCCH channel is the temporary trunking paging radio network identifier TP-RNTI; the identifier of the trunking control channel TCCH and the identifier of the TTCH channel are the temporary trunking service radio network identifier G-RNTI.

The identifier of the TPCCH channel is the temporary trunked paging radio network identifier TP-RNTI; in the air interface layer 2 protocol, the identifier of the TCCH channel and the identifier of the TTCH channel are different logical channel numbers LCID.

The execution unit is further configured to, when the trunking user terminal is a called trunking user terminal, detect the PDCCH channel after decoding the TB of the TCCH information carried on the PDSCH channel, and according to the detection The scheduling information of the TTCH channel is obtained, the TB carried on the PDSCH channel is searched, and the found TB is decoded to obtain the transmission data information.

It can be seen that in the present invention, a downlink logical channel and a downlink transmission channel for realizing the trunking service are newly added, and the downlink logical channel is the trunking paging control channel TPCCH for transmitting trunking paging control information, the trunking control channel TCCH for transmitting control information and the trunking traffic channel TTCH for transmitting data information, the downlink transport channel is the trunking paging transport channel TPCH carrying the TPCCH channel; the trunking paging control information is mapped from the TPCCH channel to the TPCH channel, and then mapped to the physical downlink by the TPCH channel Shared channel PDSCH; control information is mapped from the TCCH channel to the downlink shared channel DL-SCH, and then mapped from the DL-SCH channel to the PDSCH channel; data information is mapped from the TTCH channel to the DL-SCH channel, and then mapped by the DL-SCH channel The channel is mapped to the physical downlink shared channel PDSCH; the scheduling information of the TPCCH channel, the TCCH channel and the TTCH channel are respectively loaded on the PDSCH with their respective identifiers;

Each cluster user terminal periodically detects the physical downlink control channel PDCCH, searches for the transport block TB carried on the PDSCH channel according to the scheduling information of the found TPCCH channel, and decodes the TB to obtain the TPCCH channel The information carried; according to the information carried by the TPCCH channel, each cluster user terminal judges whether it belongs to the user terminal in the currently initiated cluster call, and if so, establishes the control plane channel of the cluster call; the user terminal is in In the control plane channel, the PDCCH channel is detected in each transmission time interval TTI, and when the scheduling information of the TCCH channel is detected, the TB carried on the PDSCH channel is searched according to the scheduling information of the TCCH channel, and the The TB carried on the PDSCH channel is successfully decoded, and the service plane channel is configured and established; the calling cluster user terminal uses the established service plane channel to initiate a speech; the called cluster user terminal detects the PDCCH channel within the TTI, and when detected When the scheduling information of the TTCH channel is carried, the TB carried on the PDSCH channel is searched according to the scheduling information of the TTCH channel, and the TB on the PDSCH channel is decoded to obtain transmission data information.

Transmission of group paging control information through TPCCH and TPCH channels reduces the signaling interaction between the calling terminal and the called terminal, thereby reducing the paging channel cycle of the air interface; Point of task classification transmission; thus further able to shorten the call set-up time, and improve resource utilization.

Description of drawings

Fig. 1 is a schematic diagram of the network architecture based on the existing TD-LTE broadband digital trunking communication system;

Fig. 2 is a schematic diagram of the downlink mapping relationship in the digital trunking communication system based on TD-LTE technology of the present invention;

FIG. 3 is a flow chart of an embodiment of a method for implementing a cluster service in the present invention;

FIG. 4 is a schematic diagram of the composition and structure of an embodiment of a cluster user terminal according to the present invention.

Detailed ways

Aiming at the problems existing in the prior art, the present invention proposes a brand-new trunking service implementation scheme, which introduces TD-LTE technology into the digital trunking communication system, thereby obtaining a digital trunking communication system based on TD-LTE technology, and based on The digital trunking communication system realizes trunking services.

FIG. 1 is a schematic diagram of a network architecture of an existing digital trunking communication system based on TD-LTE technology. As shown in Figure 1, it includes: trunking user terminals, trunking broadband wireless access subsystems, trunking network subsystems, and the like.

Among them, the trunking user terminal is connected to the trunking broadband wireless access subsystem or the trunking network subsystem through an air interface, etc., to provide users with various push-to-talk (PTT, Push-To-Talk) voice services, broadband trunking multimedia services and scheduling Function. The trunking user terminal includes a mobile terminal, a fixed station, and a dispatching station; furthermore, the mobile terminal also includes a handheld mobile station and a vehicle-mounted station, and the dispatching station also includes a wireless dispatching station and a wired dispatching station.

The trunking broadband wireless access subsystem consists of multiple enhanced eNodeBs (E-eNodeBs). The radio trunking dispatch function module RTDF (Radio Trunking Dispatch Function) in the E-eNodeB is responsible for the related processing of the trunking business in the E-eNodeB, for example, receiving the trunking control signaling from the enhanced mobility management entity eMME (MME, Mobility Management Entity), Allocate downlink shared resources for the cell where the called cluster user terminal is located, and transmit the cluster service data stream received from the serving gateway (S-GW, Serving Gateway) to the called cluster user terminal, etc.

The cluster network subsystem includes eMME, S-GW, enhanced packet data network gateway eP-GW (P-GW, PDN Gateway), enhanced home subscriber server eHSS (HSS, Home Subscriber Server) and scheduling gateway (D-GW, Dispatch Gateway). Among them, the trunking control function module (TCF, Trunking Control Function) in the eMME is the control center for realizing the trunking call, which is responsible for the authentication of the trunking user and the authorization of the trunking service, and establishes the bearer of the transmission service data flow for the successfully authenticated user; The trunking packet function module (TPF, Trunking Packet Function) in the eP-GW is used to complete the mapping, replication and distribution of the cluster service data flow, and initiate services according to the service characteristics and service quality (QoS, Quality of Service) requirements requested by users The establishment of bearer; the trunking subscriber server (TSS, Trunking Subscriber Server) in eHSS is used to store and manage the group user information related to the cluster business; D-GW is the gateway for the wired dispatcher to access the cluster network subsystem, responsible for wired dispatching Station authentication, transmission of signaling and business data between the wired dispatching station and the cluster network subsystem; in addition, D-GW is also responsible for realizing the interconnection and intercommunication between the cluster system and other cluster systems.

After adopting the digital trunking communication system shown in Figure 1, the trunking service will be carried in the packet domain, so the sharing of service channels can be fully realized, thereby greatly improving resource utilization and reducing the operating cost of the digital trunking communication system. Moreover, because TD-LTE technology adopts an all-IP flat network architecture, and the base station is directly connected to the core network, the internal signaling interaction on the network side during the call establishment process is reduced, and the call establishment time is shortened.

However, the digital trunking communication system shown in Figure 1 also has certain problems in practical applications. For example, although the network architecture of TD-LTE technology can shorten the call establishment time, in TD-LTE technology, the paging of the air interface The cycle of the control channel is long and cannot be modified. Therefore, the call establishment time is still long; in addition, the existing TD-LTE technology is designed for point-to-point communication services, and the trunking service is a point-to-multipoint service. Therefore, the existing TD-LTE technology cannot be directly applied to the trunking service.

For this reason, in the solution of the present invention, the air interface channel in the existing TD-LTE technology is modified, and a new logical channel and a new transmission channel are added. The air interface protocol of TD-LTE technology stipulates that the media access control layer (MAC, Media Access Control) provides data transmission services on logical channels, and different types of data transmission services (point-to-point and point-to-multipoint, etc.) need to correspond to different logical channel type. Therefore, in the solution of the present invention, aiming at the problem that the paging control channel period of the air interface is longer, a new downlink logical channel for carrying trunking paging control information is newly added, which is defined as trunking paging control channel (TPCCH, Trunking Paging Control Channel). The establishment of the TPCCH channel reduces the paging channel period of the air interface. In view of the point-to-multipoint characteristics of trunking services, a new downlink logical channel for control information such as trunking service call establishment, call release, and voice notification is added, which is defined as a trunking control channel (TCCH, Trunking Control Channel); The downlink logical channel used to transmit trunking point-to-multipoint service data information is defined as a trunking traffic channel (TTCH, TrunkingTraffic Channel). In addition, the transport channel is used to carry the service information provided by the physical layer, and transmit it to the MAC layer and the upper layer, and describes the characteristics of data transmission on the air interface. In the scheme of the present invention, according to the characteristics of the TPCCH channel, a new The transport channel used to carry the TPCCH channel is defined as a trunking paging transport channel (TPCH, Trunking Paging Channel). The TPCH channel has the following characteristics: broadcast in the entire group coverage area of the cell, can be dynamically mapped to physical resources, and supports Discontinuous Reception (DRX, Discontinuous Reception) mode, etc. The sending opportunity and sending cycle of the TPCCH channel can be notified to each cluster user terminal through the system broadcast message. In this way, the cycle of the paging control channel used for the cluster service on the air interface can be set arbitrarily according to needs, thus shortening the time required for the cluster service. call setup time.

Fig. 2 is a schematic diagram of the downlink mapping relationship in the digital trunking communication system based on the TD-LTE technology of the present invention, which is divided into downlink logical channels, downlink transmission channels and downlink physical channels. The newly added TPCCH, TTCH and TCCH belong to the downlink logic channel, and the newly added TPCH belongs to the downlink transmission channel. As shown in Figure 2, the mapping path of the TPCCH channel is: TPCCH channel-TPCH channel-physical downlink shared channel (PDSCH, Physical Downlink Shared Channel); the mapping path of the TCCH channel is: TCCH channel-downlink shared transport channel (DL-SCH , Downlink shared channel)-PDSCH channel; the mapping path of TTCH channel is: TTCH channel-DL-SCH channel-PDSCH channel. The scheduling information of the TPCCH channel, the TCCH channel and the TTCH channel are respectively loaded on the PDSCH with their respective identifiers. Each cluster user terminal detects the PDCCH, and searches for a corresponding transport block TB on the PDSCH channel according to the found scheduling information. Wherein, the information transmission between the PDCCH and the PDSCH is an existing technology of the TD-LTE technology, and will not be repeated here. Functions and mapping relationships of other channels shown in FIG. 2 are well known in the art and will not be repeated; in addition, the uplink mapping relationship is the same as that in the prior art.

The air interface protocol of TD-LTE technology stipulates that different types of logical channels need to be distinguished by radio network temporary identifier (RNTI, Radio Network Temporary Identifier), such as paging control channel (PCCH, Paging control channel) using paging RNTI (P-RNTI) to distinguish, and dedicated traffic channel (DTCH, Dedicated Traffic Channel) to distinguish by cell RNTI (C-RNTI); for the newly added TPCCH channel, TCCH channel and TTCH channel, it is also necessary to define corresponding In order to distinguish it from other logical channels, the scheme of the present invention stipulates that the group paging RNTI (TP-RNTI) is used to distinguish the TPCCH channel; the group service RNTI (G-RNTI) is used to distinguish the TCCH channel and TTCH channels are distinguished, and different logical channel numbers (LCIDs) are used to distinguish TCCH channels and TTCH channels in the air interface layer two protocol.

Based on the above introduction, FIG. 3 is a flow chart of an embodiment of a method for implementing a trunking service in the present invention. As shown in Figure 3, the following steps are included:

Step 301: Each cluster user terminal periodically detects a PDCCH channel scrambled by a cyclic redundancy check (CRC, Cyclic Redundancy Check) identified by a TP-RNTI at a designated location.

In practical applications, the base station will notify each cluster user of the sending opportunity and sending cycle of the TPCCH channel information on the network side through a broadcast message in advance. On which subframe of the frame (ie, PF frame) to send, the subframe is usually a P0 subframe. Subsequently, when there is information carried by the TPCCH channel that needs to be sent, the base station will send it at the above-mentioned specified position (subsequently mapped to the PDSCH channel).

After each cluster user receives the broadcast message sent by the base station, it periodically detects the PDCCH channel after CRC scrambling with the TP-RNTI identifier at the designated position; the PDCCH channel carries the scheduling information of the TPCCH channel, which is used to indicate the The position of the transport block (TB, Transport Block) of the information carried by the TPCCH channel on the PDSCH channel.

Step 302: If the scheduling information of the TPCCH channel is carried on the PDCCH channel, according to the scheduling information, a TB containing information carried by the TPCCH channel carried on the PDSCH channel is found.

In this step, if it is determined that the scheduling information of the TPCCH channel is carried on the PDCCH channel, each cluster user terminal uses the known TP-RNTI to perform CRC descrambling on the scheduling information, and obtains the TB that contains the information carried by the TPCCH channel. The location information on the PDSCH channel, and find the TB corresponding to the TPCCH channel according to the obtained location information. How the trunking user terminal obtains the TP-RNTI is well known in the art, and will not be repeated here.

Step 303: Decode the found TB.

In this step, the cluster user terminal decodes the found TB, and transmits the successful decoding result, that is, the MAC packet data unit (PDU, Packet Data Unit) to the upper layer. How to decode it into the prior art will not be repeated here. If the decoding fails, the found TB is discarded.

Step 304: According to the decoding result, the high level of each cluster user terminal judges whether it is a member of the currently initiated cluster service, and if so, establishes a control plane channel for cluster control.

The correctly decoded MAC PDU will carry information such as the group ID of the cluster service and the G-RNTI identifier. Since which groups it belongs to is known in advance, each cluster user terminal can determine whether it belongs to the G-RNTI through the group ID information. Members in the currently initiated cluster service, if yes, establish the control plane channel of the cluster call, otherwise, discard the received MAC PDU; the G-RNTI identifier is used to illustrate the TCCH channel corresponding to the currently initiated cluster service.

Wherein, establishing the control plane channel includes: establishing TCCH channel-related entities and contexts; the TCCH channel-related entities include: Packet Data Convergence Protocol (PDCP, Packet Data Convergence Protocol) entity, Radio Link Control Protocol (RLC, Radio Link Control ) entity, MAC entity, and physical layer (PHY, Physical) entity. How to establish it is well known in the art and will not be repeated here.

Step 305: After the called trunking user terminal establishes the TCCH control plane channel of the trunking call, it detects the PDCCH channel after CRC scrambling with G-RNTI in each transmission time interval (TTI, Transmission Time Interval) of the control plane channel. If it is detected that the scheduling information of the TCCH channel is carried on the PDCCH channel, the TB containing the information carried by the TCCH channel carried on the PDSCH channel is searched according to the scheduling information, and the found TB is decoded. And transmit the correctly decoded control information to the upper layer. If the decoding fails, the found control information is discarded.

The called group user performs operations such as setting up or releasing a group call according to the control information of the TCCH.

Step 306: After correctly receiving the control information of the TCCH channel, the cluster user will configure and establish the service plane channel. The calling cluster user terminal uses the established service plane channel to initiate speech; the called cluster user terminal detects the PDCCH channel after CRC scrambling with G-RNTI in each TTI, if it detects that the PDCCH channel bears the TTCH channel Scheduling information, according to the scheduling information, search for TBs carried on the PDSCH channel that include the information carried by the TTCH channel, and decode the found TBs.

After correctly receiving the TCCH channel information, the calling and called cluster user terminals can start to upload or receive cluster service data information. Specifically, the calling trunking user terminal uses the established service plane channel to initiate speech, while the called trunking user terminal detects the PDCCH channel scrambled by CRC with G-RNTI in each TTI, if in a certain TTI If it is detected that the scheduling information of the TTCH channel is carried on the PDCCH channel, the scheduling information is descrambled by using the G-RNTI obtained in step 304, and the scheduling information carried on the PDSCH channel is searched according to the scheduling information. TB of the information carried by the TTCH channel, decode the found TB, and transmit the result of successful decoding, that is, the MAC PDU carrying the trunking service data information, to the upper layer.

Subsequently, based on the periodicity of the trunking service, in order to save power, each called trunking user terminal may not detect each TTI, but periodically detect the PDCCH channel after CRC scrambling with the G-RNTI identifier, and according to The detected scheduling information of the TTCH channel is searched for the TB carried on the PDSCH channel that contains the information carried by the TTCH channel, the found TB is decoded, and the successful decoding result is transmitted to the upper layer.

That is to say, after the called trunking user terminal detects the PDCCH channel for the first time, it does not need to detect each TTI subsequently, but detects the PDCCH channel at the same position in the next period according to the periodic characteristics of the trunking service That's it. For aperiodic services, each TTI needs to be detected.

In addition, when the speaking right of the calling trunking user terminal is preempted, all called trunking user terminals, including the original calling trunking user terminal and other called user terminals Detect the PDCCH channel after CRC scrambling with the G-RNTI identifier in each TTI. If it is detected that the scheduling information of the TTCH channel is carried on the PDCCH channel, search for the TTCH channel carrying information carried on the PDSCH channel according to the scheduling information. information, and decode the found TB, and transmit the result of successful decoding to the upper layer; after that, detect the PDCCH channel after CRC scrambling with the G-RNTI identifier, and schedule according to the detected TTCH channel Information, search for the TB carried on the PDSCH channel that contains the information carried by the TTCH channel, decode the found TB, and transmit the successful decoding result to the upper layer.

It is also possible to periodically detect the PDCCH channel after CRC scrambling with the G-RNTI identifier, and search for the TB carried on the PDSCH channel that contains the information carried by the TTCH channel according to the scheduling information of the detected TTCH channel. The received TB is decoded, and the result of successful decoding is transmitted to the upper layer.

Based on the above method, FIG. 4 is a schematic diagram of a composition structure of an embodiment of a cluster user terminal according to the present invention. The trunking user terminal is applied in a digital trunking communication system based on time-division long-term evolution TD-LTE technology.

In the system, a downlink logical channel and a downlink transmission channel for realizing trunking services are newly added. The downlink logical channel is a TPCCH channel for transmitting trunking paging control information, a TCCH channel for transmitting control information, and a TTCH channel for transmitting data information. The transport channel is a TPCH channel carrying a TPCCH channel.

The group paging control information is mapped from the TPCCH channel to the TPCH channel, and then the TPCH channel is mapped to the physical downlink shared channel PDSCH; the control information is mapped from the TCCH channel to the DL-SCH channel, and then the DL-SCH channel is mapped to the PDSCH channel; The data information is mapped from the TTCH channel to the DL-SCH channel, and then the DL-SCH channel is mapped to the PDSCH channel;

Cluster user terminals include:

The detection unit 401 is used to periodically detect the PDCCH. If the scheduling information of the TPCCH channel is carried on the PDCCH channel, the transport block TB carried on the PDSCH channel is searched according to the scheduling information of the TPCCH channel, and the TB on the PDSCH channel is performed. Decoding, obtaining the information carried by the TPCCH channel, and establishing the control plane channel of the trunking call; in the control plane channel, detecting the PDCCH channel in each transmission time interval TTI, and when it is detected that the PDCCH channel bears the TCCH channel When scheduling information, search for the TB carried on the PDSCH channel according to the scheduling information of the TCCH channel, and successfully decode the TB carried on the PDSCH channel, configure and establish the service plane channel;

A judging unit 402, configured to judge whether the trunking user terminal is the calling trunking user terminal or the called trunking user terminal according to the obtained information, and notify the execution unit of the judgment result;

Executing unit 403, configured to use the established service plane channel to initiate a speech when the cluster user terminal where it is located is the calling cluster user terminal;

When the cluster user terminal where it is located is the called cluster user terminal, detect the PDCCH channel in each TTI, and when it is detected that the PDCCH channel carries the scheduling information of the TTCH channel, search for the PDSCH channel carried on the PDSCH channel according to the scheduling information of the TTCH channel TB, and decode the TB carried on the PDSCH channel to obtain transmission data information.

When the cluster user terminal where it is located is the called cluster user terminal, detect the PDCCH channel after CRC scrambling with the identifier of the TTCH channel in each TTI, and when it is detected that the PDCCH channel carries the scheduling information of the TTCH channel , according to the scheduling information of the TTCH channel, search for a TB carried on the PDSCH channel that includes the information carried by the TTCH channel, and decode the found TB.

Among them, the identifier of the TPCCH channel is TP-RNTI, the identifier of the TCCH channel and the identifier of the TTCH channel are G-RNTI. distinguish.

In addition, the execution unit 43 can be further configured to, when the trunking user terminal where it is located is the called trunking user terminal, after decoding the found TB, periodically detect the The PDCCH channel, and according to the detected scheduling information of the TTCH channel, search for the TB carried on the PDSCH channel that contains the information carried by the TTCH channel, and decode the found TB.

For the specific working process of the device embodiment shown in FIG. 4 , please refer to the corresponding description in the method embodiment shown in FIG. 3 , which will not be repeated here.

In a word, adopting the technical scheme of the present invention can not only shorten the call establishment time, but also improve resource utilization.

To sum up, the above are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (12)

1. A trunking service implementation method, applied in the digital trunking communication system based on time-division long-term evolution TD-LTE technology, is characterized in that, In the system, a downlink logical channel and a downlink transmission channel for realizing trunking services are newly added, and the downlink logical channels are the trunking paging control channel TPCCH for transmitting trunking paging control information, the trunking control channel TCCH for transmitting control information, and A trunking traffic channel TTCH for transmitting data information, and the downlink transmission channel is a trunking paging transmission channel TPCH carrying the TPCCH channel; The trunking paging control information is mapped from the TPCCH channel to the TPCH channel, and then the TPCH channel is mapped to the physical downlink shared channel PDSCH; the control information is mapped from the TCCH channel to the downlink shared channel DL-SCH, and then mapped by the DL-SCH channel To the PDSCH channel; data information is mapped from the TTCH channel to the DL-SCH channel, and then the DL-SCH channel is mapped to the physical downlink shared channel PDSCH; Respectively load the scheduling information of the TPCCH channel, TCCH channel and TTCH channel on the PDCCH with their respective identifiers; Each cluster user terminal periodically detects the physical downlink control channel PDCCH, searches for the transport block TB carried on the PDSCH channel according to the scheduling information of the found TPCCH channel, and decodes the TB to obtain the TPCCH channel information carried; According to the information carried by the TPCCH channel, each trunking user terminal judges whether itself belongs to a user terminal in the currently initiated trunking call, and if so, establishes a control plane channel of the trunking call; In the control plane channel, the user terminal detects the PDCCH channel in each transmission time interval TTI, and when detecting the scheduling information of the TCCH channel, searches for the information carried on the PDSCH channel according to the scheduling information of the TCCH channel. TB, and successfully decode the TB carried on the PDSCH channel, configure and establish a service plane channel; The calling group user terminal uses the established service plane channel to initiate a speech; The called trunking user terminal detects the PDCCH channel within the TTI, and when it detects the scheduling information carrying the TTCH channel, searches for the TB carried on the PDSCH channel according to the scheduling information of the TTCH channel, and searches for the TB carried on the PDSCH channel The TB on the channel is decoded to obtain the transmission data information. 2. The method according to claim 1, wherein the identifier of the TPCCH channel is a temporary trunking paging radio network identifier TP-RNTI; the identifier of the TCCH channel and the identifier of the TTCH channel are trunking service radio Network temporary identifier G-RNTI. 3. method according to claim 1, is characterized in that, the mark of described TPCCH channel is trunk paging radio network temporary mark TP-RNTI; In air interface layer two protocols, the mark of described TCCH channel and described The TTCH channels are identified by different logical channel numbers LCID. 4. The method according to claim 1, wherein the setting up of the control plane channel comprises: setting up entities and contexts related to the TCCH channel, and the entities related to the TCCH channel include: Packet Data Convergence Protocol PDCP entity, radio link Road control protocol RLC entity, media access control layer MAC entity and physical layer PHY entity. 5. The method according to claim 1, wherein, after searching for the TB carried on the PDSCH channel according to the scheduling information of the TTCH channel, and decoding the found TB, further comprising: Detecting the PDCCH channel, searching for TBs carried on the PDSCH channel according to the detected scheduling information of the TTCH channel, and decoding the TBs carried on the PDSCH channel to obtain transmission data information. 6. The method according to claim 5, characterized in that the method further comprises: After the speaking right of the calling group user terminal is preempted, all called group user terminals re-detect the PDCCH channel in each TTI, and when it is detected that the scheduling information of the TTCH channel is carried on the PDCCH channel, Searching for TBs carried on the PDSCH channel according to the scheduling information of the TTCH channel, and decoding the TBs carried on the PDSCH channel to obtain transmission data information. 7. The method according to any one of claims 1 to 6, wherein, before each cluster user terminal periodically detects the PDCCH channel, further comprising: The base station notifies each cluster user terminal of the sending opportunity and the sending period of the TPCCH channel through a broadcast message; the sending opportunity is the sending location information of the TPCCH channel. 8 . The method according to claim 7 , wherein the sending location information is the radio frame and subframe information used for sending the TPCCH channel; the subframe is a P0 subframe. 9. A trunking user terminal, applied in a digital trunking communication system based on time-division long-term evolution TD-LTE technology, is characterized in that, In the system, a downlink logical channel and a downlink transmission channel for realizing trunking services are newly added, and the downlink logical channels are the trunking paging control channel TPCCH for transmitting trunking paging control information, the trunking control channel TCCH for transmitting control information, and A trunking traffic channel TTCH for transmitting data information, and the downlink transmission channel is a trunking paging transmission channel TPCH carrying the TPCCH channel; The trunking paging control information is mapped from the TPCCH channel to the TPCH channel, and then the TPCH channel is mapped to the physical downlink shared channel PDSCH; the control information is mapped from the TCCH channel to the downlink shared channel DL-SCH, and then mapped by the DL-SCH channel To the PDSCH channel; data information is mapped from the TTCH channel to the DL-SCH channel, and then the DL-SCH channel is mapped to the physical downlink shared channel PDSCH; The cluster user terminal includes: The detection unit is configured to periodically detect the physical downlink control channel PDCCH, and if the PDCCH carries the scheduling information of the TPCCH channel, search for the transmission carried on the PDSCH channel according to the scheduling information of the TPCCH channel Block TB, and decode the TB on the PDSCH channel, obtain the information carried by the TPCCH channel, and establish the control plane channel of the trunking call; in the control plane channel, detect the PDCCH in each transmission time interval TTI channel, and when it is detected that the scheduling information of the TCCH channel is carried on the PDCCH channel, the TB carried on the PDSCH channel is searched according to the scheduling information of the TCCH channel, and the TB carried on the PDSCH channel is successfully decoded, configured and Establish business plane channel; The judging unit is configured to judge whether the cluster user terminal is the calling cluster user terminal or the called cluster user terminal according to the obtained information, and notify the execution unit of the judgment result; The execution unit is configured to use the established service plane channel to initiate a speech when the cluster user terminal where it is located is the calling cluster user terminal; When the cluster user terminal where it is located is the called cluster user terminal, detect the PDCCH channel in each TTI, and when it is detected that the scheduling information of the TTCH channel is carried on the PDCCH channel, according to the scheduling information of the TTCH channel Searching for TBs carried on the PDSCH channel, and decoding the TBs carried on the PDSCH channel to obtain transmission data information. 10. The trunking user terminal according to claim 9, wherein the identifier of the TPCCH channel is the temporary identifier of the trunking paging radio network TP-RNTI; the identifier of the trunking control channel TCCH and the identifier of the TTCH channel Temporarily identifies the G-RNTI for the trunking service radio network. 11. The trunking user terminal according to claim 9, wherein the identifier of the TPCCH channel is the temporary identifier TP-RNTI of the trunking paging radio network; in the air interface layer two protocol, the identifier of the TCCH channel and The identifiers of the TTCH channels are different logical channel numbers LCID. 12. The trunking user terminal according to claim 9, wherein the execution unit is further configured to, when the trunking user terminal is a called trunking user terminal, when the trunking user terminal is carried on the PDSCH channel After decoding the TB of the TCCH information, the PDCCH channel is detected, and according to the detected scheduling information of the TTCH channel, the TB carried on the PDSCH channel is searched, and the found TB is decoded to obtain the transmission Data information.

Images