WO2009062355A1

WO2009062355A1 - Method for sending multicast and broadcast service media access control layer protocol data unit

Info

Publication number: WO2009062355A1
Application number: PCT/CN2007/003980
Authority: WO
Inventors: Jianquan Song
Original assignee: Zte Corporation
Priority date: 2007-11-12
Filing date: 2007-12-29
Publication date: 2009-05-22
Also published as: CN101436943B; CN101436942A; CN101436943A; CN101436942B

Abstract

A method for sending a multicast and broadcast service media access control layer protocol data unit is provided. The method includes the steps of : the centralized scheduler in the multicast and broadcast service area converting the received multicast and broadcast service message into the multicast and broadcast service media access control layer protocol data unit of the network side, and sending it to the local scheduler in the multicast and broadcast service area, wherein the multicast and broadcast service media access control layer protocol data unit of the network side includes the header of the multicast and broadcast service and the net load of the multicast and broadcast service; and the local scheduler constructing the multicast and broadcast service media access control layer protocol data unit used for the air interface based on the net load of the multicast and broadcast service in the multicast and broadcast service media access control layer protocol data unit of the network side, and sending the multicast and broadcast service media access control layer protocol data unit used for the air interface based on the header of the multicast and broadcast service in the multicast and broadcast service media access control layer protocol data unit of the network side.

Description

Send multicast broadcast service media access control layer

TECHNICAL FIELD The present invention relates to the field of communications, and in particular, to a method for transmitting a multicast broadcast service medium access control layer protocol data unit. The requirements of the Multicast and Broadcast Service (MCBCS) are defined in the Service Provider Work Group (SPWG). In the IEEE802.16e-2005 specification, two types of multicast broadcast services are supported. (Multicast and Broadcast Service, abbreviated as MBS): An MBS service that is accessed by a single base station (BS), and an MBS service that is accessed by multiple BSs. For multi-BS access MBS services, macro-diversity is supported. To achieve macro-diversity, the same multicast mechanism (same sub-channel, symbol, modulation and coding, and permutation, etc.) must be used to transmit the same multicast broadcast at the same time. Service Medium Access Control Layer Protocol Data Unit (MBS MAC PDU). Neither the NWG protocol nor the IEEE 802.16e teaches how to implement downlink subframes that transmit the same MBS MAC PDU at the same time. SUMMARY OF THE INVENTION It is necessary to implement macro diversity of MBS services in an MBS area (a set of base stations that deliver the same multicast broadcast service, these base stations have the same multicast connection identity and security association) (that is, the terminal receives from multiple base stations) The same service, for the MBS service of multiple base stations, needs to support macro diversity), it is necessary to solve the same transmission mechanism to transmit the same MBS MAC PDU at the same time. The present invention is to solve how to schedule and construct MBS MAC PDUs for multicast broadcast services, and to ensure that MBS MAC PDUs can be transmitted at the same time. The method for transmitting a multicast broadcast service medium access control layer protocol data unit according to the present invention includes the following steps: Step 1: The centralized scheduler in the multicast broadcast service area converts the received multicast broadcast service into The network side multicast broadcast service medium access control layer protocol data unit is sent to the local scheduler in the multicast broadcast service area, where the network side multicast broadcast service medium access control layer protocol data unit includes a multicast broadcast service header and Multicast broadcast service payload; and step 2, the local scheduler is located at the network side multicast broadcast service media access control layer from the centralized scheduler The multicast broadcast service payload in the protocol data unit is configured for the multicast broadcast service medium access control layer protocol data unit of the air interface, and according to the network side multicast broadcast service medium access control layer protocol of the 11 centralized scheduler The multicast broadcast service header in the data unit transmits a multicast broadcast service medium access control layer protocol data unit for the air interface to the mobile terminal. Step 1 includes the following steps: The centralized scheduler selects all or part of the multicast broadcast service packets received as the multicast broadcast service payload; the centralized scheduler calculates the multicast broadcast service payload to be converted into a physical layer burst. The position occupied in the downlink subframe and the absolute time transmitted on the air interface and/or the calculation of the next scheduling information (ie, the next MBS MAP message), the position occupied in the downlink subframe after the transition to the physical layer burst, and the air interface The absolute time of the transmission, and the calculated location information, time information, necessary media access control layer (MAC) to physical layer (PHY) mapping rules, necessary PHY characteristics parameters (including modulation and coding methods, code repetitions) Hybrid automatic repeat request (HARQ) parameter setting, gain (Boosting) parameter, subchannel subcarrier alignment characteristics, etc., and multicast broadcast service payload, location information, time information, necessary MAC to PHY mapping rules And the code length occupied by the necessary PHY feature parameters as the multicast broadcast service header; and the centralized scheduler utilization group Payload broadcast traffic and multicast broadcast service header configured BCMCS network media access control layer protocol data unit sent to the local scheduler. The centralized scheduler decides to select some or all of the multicast broadcast service packets as the multicast broadcast service payload according to one or more of the following contents: the quality of service characteristics of the multicast broadcast service, and the current downlink subframe available resources. , MAC to PHY mapping rules, physical layer characteristics parameters. The centralized scheduler sends the network side multicast broadcast service medium access control layer protocol data unit to all local schedulers in the multicast broadcast service area at one time, or separately to each local according to the delay characteristics of each local scheduler. The scheduler sends a network side multicast broadcast service medium access control layer protocol data unit. The network side multicast broadcast service medium access control layer protocol data unit further includes a check code. In step 2, the local scheduler also performs integrity check on the network side multicast broadcast service medium access control layer protocol data unit according to the check code. If the network side multicast broadcast service medium access control layer protocol data unit fails the integrity check, the local scheduler determines whether to initiate a retransmission request or perform error processing according to a predetermined policy. The header of the network side multicast broadcast service medium access control layer protocol data unit may be separately sent as control information to the local service scheduler in the MBS Zone. In the second step, the local scheduler further constructs a multicast broadcast mapping information unit according to the information in the multicast broadcast service header in the data access layer protocol data unit of the network side multicast broadcast service medium.

(MBS MAP IE) and Multicast Broadcast Mapping (MBS MAP) messages, where the MBS MAP message contains zero or more of the following information elements: Multicast Broadcast Data Information Element (MBS DATA IE;), Extended Multicast Broadcast Data Information Unit (Extended MBS DATA IE), Multicast Broadcast Data Time Diversity Information Unit (MBS DATA Time Diversity IE). Optionally, the centralized scheduler may also construct these information elements and send them directly to the local scheduler in the multicast broadcast service header. In the second step, the local scheduler constructs the next one according to the absolute time and location information of the next MBS MAP message in the multicast broadcast service header in the data unit of the network side multicast broadcast service medium access layer protocol. The absolute time of the MBS MAP message sent over the air interface and the location information mapped to the PHY. If the centralized scheduler output in step 1 includes multiple instances of the multicast broadcast service data information unit (MBS DATA IE, Extended MBS DATA IE, MBS DATA Time Diversity IE), the centralized scheduler is used. On the one hand, the output of the device is taught to the upper layer service in the payload: according to the unit number, and the scheduling information of each instance is mapped to the PHY location information, in addition to the absolute time of the corresponding payload air interface transmission of the instance. It is necessary to include the necessary fields (mainly PHY characteristic parameters) of each instance of the base station configuration, and also needs to include the start and end points of the corresponding payload number of each instance scheduling information, and if the corresponding payload contains fragmentation information, it should also include fragmentation. information. In addition, the centralized scheduler output also needs to include the absolute time of the next scheduling information (ie, MBS MAP message) corresponding to each instance sent over the air interface and the location information mapped to the PHY. In step 2, the local scheduler sends the payload corresponding to each instance to the absolute time sent by the air interface. In step 2, the local scheduler constructs the MAC PDU and the DL MAP IE of the entire downlink subframe according to the multi-base station MBS service scheduling result and the local service scheduling result received from the centralized scheduler, and passes the entire downlink subframe through the air. The interface is sent out. The centralized scheduler calculates the absolute time of sending the multicast broadcast service payload on the air interface according to the delay between the centralized scheduler and the local scheduler reported by each local scheduler, where the delay includes at least the transmission delay. And processing delays. The delay may also include a retransmission delay and a time for the multicast broadcast service to be scheduled in advance. The delay may also include that the local scheduler reports the network side that it receives. The time difference between the time when the multicast broadcast service medium access control layer protocol data unit is determined and the time determined by the time information in the multicast broadcast service header. Optionally, the centralized scheduler calculates an absolute time for sending the multicast broadcast service payload on the air interface according to the maximum value in the delay reported by each local scheduler. The centralized scheduler may also receive the time and multicast broadcast of the network access multicast layer medium access control layer protocol data unit that is reported by each local scheduler according to the maximum value of the delays reported by each local scheduler. The time difference between the times determined by the time information in the service header, and the absolute time at which the payload of the multicast broadcast service is sent over the air interface is calculated. Optionally, the centralized scheduler uses the sum of the current absolute time and the network side delay as the absolute time for transmitting the multicast broadcast service payload on the air interface. The local scheduler reports the reception to the centralized scheduler when the local scheduler receives the network side multicast broadcast service medium access control layer protocol data unit at a later time than the time information determined in the multicast broadcast service header. The time difference between the time when the network side multicast broadcast service medium access control layer protocol data unit is determined and the time determined by the time information in the multicast broadcast service header. When the local scheduler receives the network side multicast broadcast service medium access control layer protocol data unit for a time earlier than the time information determined in the multicast broadcast service header, the local scheduler determines whether to win according to a predetermined policy. The time difference between the time when the network side multicast broadcast service medium access control layer protocol data unit is received and the time determined by the time information in the multicast broadcast service header is reported to the centralized scheduler. Wherein, for the case where the centralized scheduler adopts one-time transmission and separate transmission, the local scheduler adopts different predetermined policies to make a decision. The centralized scheduler according to the physical layer characteristic parameters of the multicast broadcast service (including modulation and coding mode, code repetition number, HARQ parameter setting, and arrangement characteristics of subchannel subcarriers, etc.), multicast broadcast service payload, and downlink subroutine The available radio resources in the frame calculate the position occupied by the multicast broadcast service payload in the downlink subframe after being converted into a physical layer burst. The network side multicast broadcast service medium access control layer protocol data unit further includes a multicast broadcast service downlink interval usage code and a description thereof, and/or a multicast broadcast service arrangement characteristic description identifier and a description thereof. The local scheduler and the centralized scheduler obtain the multicast broadcast by receiving the downlink broadcast service use code of the multicast broadcast service periodically and updated by the network manager and its description and/or the multicast broadcast service arrangement characteristic description identifier and the description thereof. The service downlink interval usage code and its description and/or the multicast broadcast service arrangement feature description identifier and its description. Optionally, the local scheduler receives the centralized scheduler The downlink broadcast service usage code and its description and/or the multicast broadcast service arrangement characteristic description identifier and the description thereof sent to the multicast broadcast service periodically or updated to obtain the downlink interval use code of the multicast broadcast service and its description and/or Or the multicast broadcast service arrangement description identifier and its description. The present invention can implement a multicast broadcast service supporting macro diversity, that is, all base stations in the MBS Zone range transmit the same at the same time using the same transmission mechanism (using the same subchannel, symbol, modulation and coding scheme, arrangement, etc.) MBS MAC PDIL Additionally, the present invention is capable of integrity checking of MBS MAC PDUs transmitted by the centralized scheduler to the local scheduler. At the same time, according to the present invention, the delay characteristic on the network side can be updated according to the adjustment amount fed back by the local scheduler; the centralized scheduler can send the network side MBS MAC PDU to the local scheduler at one time, so that the local scheduling with less delay is performed. The device will receive the MBS MAC PDU on the network side in advance, and it will take a long time for the cache to be sent over the air interface. The centralized scheduler may also send the network side MBS MAC PDU to the local scheduler according to the delay characteristics of each local scheduler, so that each local scheduler receives the time after being buffered or cached for a small time and then sent through the air interface. A one-time transmission requires a cache with a large number of local schedulers that consume less delay, and a separate cache that consumes more centralized schedulers. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a schematic diagram of a network composed of a centralized scheduler and a local scheduler; and FIG. 2 is a schematic diagram of inputs and inputs of a centralized scheduler. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The macro diversity of MBS is to ensure that each base station in the MBS Zone transmits the same content at the same time and at the same frame position, which requires a two-layer scheduler to cooperate. First, there is a centralized scheduler in the MBS Zone to complete the scheduling of the multi-base station MBS service, and send the scheduling result to the local scheduler of each base station in the MBS Zone. Second, there is one for each base station in the MBS Zone. Local scheduler, the local scheduler not only needs to complete the scheduling of local services (including unicast services and MBS services of a single BS), but also needs to be received from the centralized scheduler. The multi-base station MBS service scheduling result is combined with the local scheduling result, and then the combined scheduler sends the combined scheduling result through the air interface. That is, the method for transmitting a multicast broadcast service medium access control layer protocol data unit according to the embodiment of the present invention includes the following steps: Step 1: The broadcast scheduler in the multicast broadcast service area receives the broadcast broadcast The service packet is changed to the network side multicast broadcast service medium access control layer protocol data unit and sent to the local scheduler in the multicast broadcast service area i or, wherein the network side multicast broadcast service medium access control layer protocol data unit The multicast broadcast service header and the multicast broadcast service payload are included; and the second scheduler is configured according to the multicast broadcast service payload structure in the network side multicast broadcast service medium access control layer protocol data unit from the centralized scheduler. a multicast broadcast service medium access control layer protocol data unit for the air interface, and sending the multicast broadcast service header in the network side multicast broadcast service medium access control layer protocol data unit from the centralized scheduler to the mobile terminal Multicast broadcast service medium access control layer protocol data unit for air interface. The header in the network access control layer protocol data unit of the network side multicast broadcast service may be separately sent to the local service scheduler in the MBS Zone as the 4 air system information. As shown in Figure 1, the centralized scheduler can be located in the access network gateway (ASN-GW), in a selected BS, or in a separate external entity, but the local scheduler is always located in the BS. Among them, the centralized scheduler performs the following functions:

1. Receive MBS messages from other functional entities (for example, multicast routers, etc.) and place the received MBS messages in the cache.

2. The Quality of Service (QoS) feature of the MBS service, the burst characteristics, and the scheduling characteristics of the downlink subframes that need to be occupied, select some or all of the MBS packets in the cache as the payload, and calculate The payload is converted into position information occupied in the downlink subframe after the physical layer burst. Optionally, the next scheduling information is calculated, that is, the location information occupied by the next MBS MAP message in the downlink subframe after being converted into a physical layer burst.

3. Determine the absolute time the payload is sent over the air interface. Optionally, the next scheduling information is determined, that is, the absolute time that the next MBS MAP message is sent over the air interface.

4. Construct the MBS Header. In addition to the length information of the MBS MAC PDU, the MBS Header needs to include synchronization information from the centralized scheduler to the local scheduler. Local scheduling in the base station These synchronization information is used to construct the necessary fields of the MBS MAP IE and the MBS MAP message. The synchronization information includes part or all of the following: current scheduling information, the next scheduling information, that is, the absolute time that the next MBS MAP message is sent over the air interface, and the burst location information at the physical layer. The current scheduling information includes some or all of the following contents: Absolute time of the current scheduled payload transmission, and burst location information occupied by the physical layer, physical modulation and coding mode, number of coding repetitions, HARQ parameter setting, Boosting, multicast connection identifier/ Logical connection identifier (MCID/LCID), and physical layer burst arrangement. The content that is not dynamically changed in the synchronization information can also be transmitted from the centralized scheduler to the local scheduler during the establishment of the MBS service, and is not included in the synchronization information in the MBS Header. 5. Through the above steps, the centralized scheduler converts the MBS message into a Media Access Control (MAC) Protocol Data Unit (MBS MAC PDU) of the network side MBS, including the MBS Header and the payload.

6. Consider data integrity, you can add a checksum at the end of the MBS MAC PDU.

7. Send the grouped MBS MAC PDUs to all local schedulers in the MBS Zone. When the centralized scheduler sends the network side MBS MAC PDUs to all local schedulers in the MBS Zone, it can be sent all at once or according to the delay characteristics of each local scheduler. The network side multicast broadcast service medium access control layer protocol data unit can be sent as a control information to the local service scheduler in the MBS Zone. Figure 2 shows the input and output of the centralized scheduler. The output of the centralized scheduler is the network side MBS MAC PDU, which contains the following parts:

1. MBS Header, which is a required part.

2. Payload Payload, which is a required part. The payload is part or all of the MBS 4 message selected by the centralized scheduler from the receive buffer, or it can be part of an MBS 4 message.

3. Check code, which is an optional part. The school weight can be used for data integrity protection. Among them, the check code can use a cyclic redundancy check code (CRC). Among them, MBS Header contains some or all of the following fields:

1. Length. This refers to the length of the MBS MAC PDU from the centralized scheduler to the local scheduler. 2. The BS is used to construct the necessary fields for the MBS MAP IE and MBS MAP messages. The MBS MAP message further includes three information elements: MBS DATA IE, Extended MBS DATA IE, MBS DATA Time Diversity IE, and the MBS MAP message may include zero or more instances of each of the above information elements, each of each information element. Each instance contains the relevant field of the scheduling information corresponding to the payload of the instance and the related field of the next MBS MAP message corresponding to the instance. These fields must be included in the MBS Header, which are respectively described as follows:

• 2.1 MBS Header needs to include the current scheduling information corresponding to each instance. The current scheduling information corresponding to each instance includes some or all of the following contents: the absolute time of the current scheduled payload transmitted on the air interface, and the burst location information occupied by the physical layer, the physical modulation and coding mode, the number of coding repetitions, and the HARQ parameter setting. , Boosting, MCID/LCID, and physical layer burst column mode. The absolute time that the current scheduled payload is sent over the air interface can be represented by a frame number. If the content that is not dynamically changed in the current scheduling information is transmitted from the centralized scheduler to the local scheduler during the MBS service establishment process, it is not included in the synchronization information in the MBS Header. The physical layer burst occupancy location information can be described in the manner of 802.16e-2005 (ie, the starting point of the occupied subchannels and symbols, and the number of subchannels and symbols occupied), or a more optimized description manner. description.

2.2 If the output of the centralized scheduler contains multiple instances, the MBS Header also needs to contain current scheduling information for multiple instances. At this time, in addition to the information in 2.1, the current scheduling information of each instance needs to increase the starting point and ending sequence number of the payload of the instance in the MBS MAC PDU, which means that each upper layer service in the payload needs to be simultaneously transmitted. The SDUs coming in are numbered. At the same time, if the current scheduling information of an instance includes the upper layer SDU fragment, the current scheduling information includes the fragmentation information in addition to the start and end point information of the corresponding payload of the instance.

2. The 3 MBS Header also needs to include the next scheduling information for each instance. That is, the absolute time of the next MBS MAP message corresponding to each instance is sent over the air interface and the burst location information is occupied at the physical layer. The absolute time transmitted on the air interface in the next scheduling information can be represented by the frame number. The centralized scheduler determines the frame sequence number in the MBS Header (that is, the payload corresponding to each instance and the time each instance sends the next scheduling information on the air interface) as follows:

1. The local scheduler in the MBS Zone (located on the base station) reports the delay between the centralized scheduler and the local scheduler to the centralized scheduler; where the delay includes at least the transmission delay + the processing delay; , the reported delay should consider the retransmission delay, retransmission delay and each retransmission The time required is related to the number of retransmissions allowed. In addition, the delay of reporting may also be considered to add delay adjustment, and the time for scheduling the MBS service in advance may be included in the delay adjustment amount.

2. The centralized scheduler records all the delays reported from the local scheduler, and selects the maximum delay as the delay on the network side; the centralized scheduler can add a delay adjustment amount to the network based on the selected maximum delay. The delay of the side, the time of scheduling the MBS service in advance can be included in the delay adjustment amount. In addition, the centralized scheduler can update the delay of the local scheduler and the delay of the network side according to the delay adjustment amount fed back by the local scheduler.

3. When constructing the MBS MAC PDU, the centralized scheduler determines that the absolute time sent by the corresponding payload of each instance on the air interface is the current absolute time plus the delay on the network side; the centralized scheduler converts the absolute time sent by the air interface. It is the frame number and is filled in the current scheduling information of each instance in the MBS Header.

4. The centralized scheduler determines the absolute time sent by the next scheduling information of each instance (ie, the next MBS MAP message) on the air interface according to the QoS characteristics of the MBS service, and converts it into a frame number and fills it in the MBS Header. The method for determining the physical layer burst position occupied by the payload corresponding to each instance in the MBS MAC PDU is as follows:

1. Calculate according to the PHY characteristic parameters of the current MBS service (including the downlink modulation and coding scheme, the code repetition number, the HARQ parameter, the arrangement characteristics of the subchannel subcarriers, etc.).

2. Calculated based on the available radio resources in the downlink subframe according to the MBS burst. 3. Calculate based on the QoS characteristics of the current MBS service. The method for determining the next scheduling information corresponding to each instance (that is, the MBS MAP message occupies the physical layer burst position) is as follows:

1. Calculate according to the downlink burst PHY characteristic parameters (including the downlink modulation and coding scheme, the number of code repetitions > the HARQ parameter, the arrangement characteristics of the subchannel subcarriers, etc.) of the next MBS MAP message.

2. The next MBS MAP message is sent according to the available radio resources in the downlink subframe. In the MBS service, the modulation coding method and the number of coding repetitions should be considered. Scope, on the other hand, consider the service QoS characteristics, especially the bit error rate characteristics allowed by the service. If MBS DIUC is used to describe the modulation and coding mode of the MBS service, that is, the burst characteristics of the MBS service, there are multiple ways to implement the local scheduler to obtain the MBS DIUC and its corresponding burst characteristic description. Method 1: The network manager configures different MBS DIUC values and their corresponding burst characteristics, and periodically sends them to the local scheduler within the centralized scheduler and MBS Zone; if a change occurs, immediate synchronization is required. Method 2: The centralized scheduler periodically sends the MBS DIUC and its corresponding burst characterization to the local scheduler. If a change occurs, it needs to be synchronized immediately. Method 3: During the establishment of the MBS service, the centralized scheduler sends the MBS DIUC and its corresponding burst characteristic description to the local scheduler. If the MBS DIUC value of the service is not allowed to change during the process of the MBS service, the centralized scheduler describes the MBS DIUC used in the MBS service or directly describes the burst characteristics. Bring to the local scheduler. If the MBS service can dynamically change the value of the MBS DIUC, the MBS DIUC may be included in the MBS Header of the network side MBS MAC PDU. The MBS Permutation ID used in the downlink subframe of the MBS service indicates the subchannel and the subcarrier arrangement adopted by the burst corresponding to the MBS service in the downlink subframe, and all subchannel multiplexing is generally selected for the MBS service ( The way of FUSC) or the way of partial subchannel multiplexing (PUSC) of all subchannels. There are several ways to get the local scheduler to get the MBS Permutation ID and its description. Method 1: It can be configured in the Network Manager and sent periodically to the centralized scheduler and the local scheduler within the MBS Zone; if a change occurs, immediate synchronization is required. Method 2: The centralized scheduler periodically broadcasts to the local scheduler. If a change occurs, it needs to be synchronized immediately. Method 3: During the MBS service establishment process, the centralized scheduler sends the MBS Permutation ID and its description adopted by the MBS service to the local scheduler. If for a specific MBS service, the service is in the process of its MBS Permutation

The ID is not allowed to change. In the MBS service establishment process, the centralized scheduler brings the MBS Permutation ID adopted by the MBS service to the local scheduler. If the MBS service can dynamically change its permutation characteristics, the #column attribute value MBS Permutation ID may be included in the MBS Header of the network side MBS MAC PDU. After the centralized scheduler constructs the network side MBS MAC PDU, it needs to be sent to the MBS Zone. All local schedulers in the range, the centralized scheduler can send all local schedulers all at once or according to the delay characteristics of each local scheduler. The one-time transmission is that the centralized scheduler meets the transmission time required by the local scheduler with the largest delay, and sends the MBS MAC PDU to all local schedulers, so that the local scheduler with less delay needs to cache longer after receiving the MBS MAC PDU. After the time can be sent on the air interface. The separate dispatcher is sent to the local scheduler with large delay first, and the local scheduler with small backward delay is sent, that is, all local schedulers receive the MBS MAC PDU sent by the centralized scheduler at almost the same time. , thereby reducing the requirement of a local scheduler cache with a small latency. The local scheduler in the base station performs the following functions: 1. Receives MBS MAC PDUs from the centralized scheduler; if the network side MBS MAC

If the PDU contains an integrity check, the integrity face is first performed. If the integrity check is performed, on the one hand, the MBS MAP IE and the MBS MAP message are constructed according to the synchronization information in the MBS Header, and on the other hand, the payload from the centralized scheduler is reconstructed into the air according to the synchronization information in the MBS Header. The MBS MAC PDU of the interface is finally transmitted according to the absolute time sent by the air interface in the synchronization information in the MBS Header, and the MBS MAP PDU mapping of the air interface is sent to the burst in the physical layer. When the MBS MAP IE and the MBS MAP message are constructed according to the synchronization information in the MBS Header, the values of some fields can be directly used, and the values of some fields need to be converted; for example, the local scheduler constructs one of the information elements MBS DATA IE in the MBS MAP message. When the current scheduling information of the instance, the value of the frame offset field is constructed according to the frame number corresponding to the MBS Header and the current frame number, and the next scheduling information corresponding to the instance (ie, the next MBS MAP message) is also constructed. When the relevant field is used, the value of the frame offset field is constructed by the frame number corresponding to the MBS Header and the current frame number.

2. If the integrity check is not passed, then the pre-strategy can decide whether to initiate a retransmission request or to handle the error. The error handling includes discarding the MBS service scheduling result of the multiple BSs received from the centralized scheduler.

3. When the local scheduler performs local scheduling (including scheduling of MBS services for unicast and single BS), combined with the received scheduling result of the centralized scheduler for MBS services of multiple BSs, the utilization efficiency of the radio resources is improved. Because the scheduling of the MBS service of the multi-BS is always scheduled in advance by the centralized scheduler, when the local scheduler performs local scheduling, the radio resources not occupied by the MBS service of the multi-BS can be used for local scheduling. 4. The local scheduler constructs the MAC PDU and the DL MAP IE of the entire downlink subframe according to the scheduling result of the centralized scheduler and the scheduling result of the local scheduler, and transmits the entire downlink subframe through the air interface.

5. The delay adjustment function from the centralized scheduler to the local scheduler. The adjustment function includes: if the time when the local scheduler receives the network side MBS MAC PDU from the centralized scheduler is later than the transmission time of the air interface, the local scheduler calculates the time difference, whether the centralized scheduler uses one-time transmission or separate In the sending mode, the local scheduler needs to report the time difference to the centralized scheduler. If the local scheduler receives the network side MBS MAC PDU earlier than the air interface transmission time, the local scheduler calculates the time difference value and determines whether the difference is sent to the centralized scheduler. If the centralized scheduler uses a one-time transmission policy, the local scheduler needs to compare the time difference to a preset threshold of one. If it is greater than the threshold 1, the time difference value needs to be reported to the centralized scheduler. If the centralized scheduler uses a separate policy based on the delay characteristics of each local scheduler, the local scheduler needs to compare the time difference to a preset threshold of 2. If it is greater than the threshold 2, the time difference needs to be reported to the centralized scheduler. The above is only the embodiments of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. All modifications, equivalents, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the appended claims.

Claims

A method for transmitting a data unit of a medium access control layer protocol of a multicast broadcast service, characterized in that the following steps are included:

Step 1: The centralized scheduler in the multicast broadcast service area converts the received multicast broadcast service into a network-side multicast broadcast service medium access control layer protocol data unit and sends the data to the multicast broadcast service area. a local scheduler, where the network side multicast broadcast service medium access control layer protocol data unit includes a multicast broadcast service header and a multicast broadcast service payload;

Step 2: The local scheduler constructs a multicast for the air interface according to the multicast broadcast service payload in the network side multicast broadcast service medium access control layer protocol data unit from the centralized scheduler Broadcasting a service medium access control layer protocol data unit, and transmitting, according to the multicast broadcast service header in the network side multicast broadcast service medium access control layer protocol data unit from the centralized scheduler, to the mobile terminal A multicast broadcast service medium access control layer protocol data unit for an air interface. The method according to claim 1, wherein the step 1 includes the following steps: the centralized scheduler selects all or part of the received multicast broadcast service packet as the multicast broadcast service payload. ;

The centralized scheduler calculates a location occupied by the multicast layer service payload in the downlink subframe after the physical layer burst and an absolute time sent on the air interface, and/or calculates the next scheduling information to be converted to a location occupied by the physical layer burst in the downlink subframe and an absolute time transmitted on the air interface, and using the calculated location information, time information, and the multicast broadcast service payload as the group Broadcast broadcast service header;

The centralized scheduler uses the multicast broadcast service payload and the multicast broadcast service to construct the network side multicast broadcast service medium access control layer protocol data unit to send to the local scheduler. The method according to claim 2, wherein the centralized scheduler #> decides to select part or all of the multicast broadcast service message as the multicast broadcast according to one or more of the following contents: Service Payload: Quality of service characteristics of the multicast broadcast service, available resources of the current downlink subframe, mapping rules from the medium access control layer to the physical layer, and physical layer characteristics.

4. The method according to claim 3, wherein the centralized scheduler sends the network side multicast broadcast service medium access control layer protocol data unit to the multicast broadcast service area at one time The network-side multicast broadcast service medium access control layer protocol data unit is sent to each of the local schedulers by the time delay characteristics of all the local schedulers in the local scheduler.

The method according to claim 4, wherein the network side multicast broadcast service medium access control layer protocol data unit further includes a check code.

The method according to claim 5, wherein, in the step 2, the local scheduler further performs, according to the check code, the network side multicast broadcast service medium access control layer protocol data. The unit performs an integrity check.

The method according to claim 6, wherein if the network side multicast broadcast service medium access control layer protocol data unit fails the integrity check, the local scheduler determines whether according to a predetermined policy. Initiate a retransmission request or perform error handling.

8. The method of claim 7, wherein in the second step, the local scheduler # is in the group in the network side multicast broadcast service medium access control layer protocol data unit. The information in the broadcast broadcast service header constructs a multicast broadcast mapping information unit and a multicast broadcast mapping message, where the multicast broadcast mapping message includes zero or more instances of the following information units: a multicast broadcast data information unit, The multicast broadcast data information unit and the multicast broadcast data time diversity information unit are extended.

The method according to claim 8, wherein in the step two, the local scheduler is configured according to the group in the network side multicast broadcast service medium access control layer protocol data unit The broadcast broadcast service payload and its own scheduling result construct the multicast broadcast service medium access control layer protocol data unit for the air interface.

The method according to claim 8, wherein, in the step 1, the centralized scheduler further constructs the necessary information of the following information units: a multicast broadcast mapping information unit, a multicast broadcast mapping, where The necessary information of the multicast broadcast mapping includes necessary information of zero or more instances of the following information unit: a multicast broadcast data information unit, an extended multicast broadcast data information unit, and a multicast broadcast data time diversity information unit, The centralized scheduler constructs the necessary information to be sent to the local scheduler as part of the multicast broadcast service header.

The method according to any one of claims 1 to 10, wherein the centralized scheduler is configured according to the centralized scheduler reported by each local scheduler to each of the local schedulers. The delay, the absolute time of the multicast broadcast service payload corresponding to the instance of each multicast broadcast data unit being sent on the air interface, and the next scheduled information related to each multicast broadcast data information unit instance being sent over the air interface Time, wherein the delay includes at least a transmission delay and a processing delay.

12. The method according to claim 11, wherein the delay further comprises a retransmission delay.

13. The method according to claim 12, wherein the delay further comprises a time for the multicast broadcast service to be scheduled in advance.

The method according to any one of claims 1 to 10, wherein the centralized scheduler calculates the air interface transmission station according to the maximum value of the delays reported by each local scheduler. The absolute time of the multicast broadcast service payload.

The method according to any one of claims 1 to 10, wherein the centralized scheduler uses the sum of the current absolute time and the network side delay as the multicast broadcast service on the air interface. The absolute time of the payload.

The method according to claim 13, wherein the time when the local scheduler receives the network side multicast broadcast service medium access control layer protocol data unit is later than the multicast broadcast service header And the time when the local scheduler determines the time when the local scheduler receives the network side multicast broadcast service medium access control layer protocol data unit from the centralized scheduler The time difference between the times determined by the time information in the broadcast service #艮头.

The method according to claim 13, wherein when the local scheduler receives the network side multicast broadcast service medium access control layer protocol data unit, the time is earlier than the multicast broadcast service 4 When the time information in the header is determined, the local scheduler determines, according to a predetermined policy, whether to receive the time and the group of the network side multicast broadcast service medium access control layer protocol data unit The time difference between the times determined by the time information in the broadcast broadcast service header is reported to the centralized scheduler.

18. The method according to claim 17, wherein the local scheduler uses different predetermined policies to make a decision for the centralized scheduler to use one-time transmission and separate transmission.

The method according to claim 16, wherein the delay further includes a time reported by the local scheduler to receive the network access control layer protocol data unit of the network side multicast broadcast service. a time difference between times determined by the time information in the multicast broadcast service header.

The method according to claim 17, wherein the delay further includes a time reported by the local scheduler to receive the network access control layer protocol data unit of the network side multicast broadcast service. a time difference between times determined by the time information in the multicast broadcast service header.

The method according to claim 14, wherein when the local scheduler receives the network side multicast broadcast service medium access control layer protocol data unit, the time is later than the multicast broadcast service^ When the time information in the header is determined, the local scheduler reports to the centralized scheduler the time at which the network side multicast broadcast service medium access control layer protocol data unit is received and the group The time difference between the times determined by the time information in the broadcast service header.

The method according to claim 14, wherein the time when the local scheduler receives the network side multicast broadcast service medium access control layer protocol data unit is earlier than the multicast broadcast service header When the time information in the time is determined, the local scheduler determines, according to a predetermined policy, whether to receive the time of the network side multicast broadcast service medium access control layer protocol data unit and the multicast broadcast The time difference between the times determined by the time information in the service header is reported to the centralized scheduler.

23. The method according to claim 22, wherein, for the case where the centralized scheduler uses one-time transmission and separate transmission, the local scheduler uses different predetermined policies to determine the decision.

The method according to claim 23, wherein the centralized scheduler is based on a maximum value of delays reported by each local scheduler and a received report reported by each local scheduler The time of the network side multicast broadcast service medium access control layer protocol data unit and the group The time difference between the times determined by the time information in the broadcast service header is calculated, and the absolute time at which the multicast broadcast service payload is transmitted on the air interface is calculated.

The method according to claim 11, wherein the centralized scheduler calculates, according to the downlink burst characteristic of the multicast broadcast service, that the payload of the multicast broadcast service is changed to a physical layer burst and then downlink The position occupied in the sub-frame.

The method according to claim 25, wherein the centralized scheduler converts the sub-channel, and/or sub-occupied in the downlink subframe after the multicast broadcast service payload is converted into a physical layer burst. The carrier characteristic calculates a position occupied by the multicast broadcast service payload into a downlink subframe after being converted into a physical layer burst.

The method according to claim 26, wherein the centralized scheduler calculates, according to available radio resources in the downlink subframe, that the multicast broadcast service payload is converted into a physical layer burst and is in a downlink subframe. Occupied position.

The method according to claim 27, wherein the network side multicast broadcast service medium access control layer protocol data unit further includes a downlink broadcast service downlink interval usage code and its description and/or multicast. The broadcast service arrangement description identifier and its description.

The method according to claim 28, wherein the local scheduler and the centralized scheduler receive a downlink broadcast service usage code and a description thereof by using a multicast broadcast service periodically or updated by the network manager. The multicast broadcast service arrangement description identifier and its description are used to obtain the downlink broadcast service downlink interval usage code and its description and/or the multicast broadcast service 4 non-column feature description identifier and description thereof.

The method according to claim 28, wherein the local scheduler receives a downlink broadcast service usage code and a description thereof and/or a multicast broadcast service sent to the centralized scheduler periodically or during an update. Or the multicast broadcast service 4 non-column feature description identifier and the description thereof to obtain the downlink broadcast service downlink interval usage code and its description and/or the multicast broadcast service arrangement feature description identifier and a description thereof.

The method according to claim 29 or 30, characterized in that, in the process of establishing a multicast broadcast multimedia service, part or all of the mapping rule of the medium access control layer to the physical layer and the physical layer characteristic parameter are not transmitted. The parameter of the multicast broadcast service header further includes part or all of the mapping rules of the medium access control layer to the physical layer and the physical layer characteristic parameters.

The method according to claim 31, wherein the multicast broadcast service header further includes a length of part or all of the content of the network side multicast broadcast service medium access control layer protocol data unit.

33. The method according to claim 32, wherein if the multicast broadcast service payload is associated with a multicast broadcast data information unit, an extended multicast broadcast data information unit, and a multicast broadcast data time diversity information unit Corresponding to 0 or more instances, the centralized scheduler determines a payload range corresponding to each of the instances, calculates an absolute time of the payload range corresponding to each instance over the air interface, and each of the described The payload range corresponding to the instance is mapped to the location occupied by the physical layer, and the absolute time transmitted by the next scheduling information corresponding to each instance on the air interface and the position occupied by the physical layer, and corresponding to each of the instances The payload range, the absolute time of the payload range transmitted on the air interface, and the location information occupied by the physical layer and the absolute time and location information sent by the air interface on the next scheduling information corresponding to each of the instances are included in the multicast. Broadcast service header.

34. The method according to claim 32, wherein if the payload range corresponding to the instance is not an integer number of uplinks in the multicast wide service payload, the description of the instance includes The net load is the fragmentation information of the text.

The method according to claim 33 or 34, wherein the centralized scheduler stores the payload corresponding to each instance by numbering the upper layer information included in the multicast broadcast service payload The range is marked.

The method according to claim 35, wherein the centralized scheduler sends the multicast broadcast service header before or after transmitting the multicast broadcast service payload to the local service scheduler. The control information is separately sent to the local service scheduler.

37. The method according to claim 36, wherein the physical layer characteristic parameter is part or all of the following parameters: modulation coding mode, code repetition number, hybrid automatic repeat request parameter setting, gain parameter, sub Arrangement characteristics of channel subcarriers.

38. The method according to claim 37, wherein the next scheduling information refers to a next multicast broadcast mapping message.