Carrier aggregation downlink data distribution method

Abstract

The invention discloses a carrier aggregation downlink data distribution method, which comprises the following steps of: distributing downlink data on a PDCP (Packet Data Convergence Protocol) layer, distributing one path to an RLC (Radio Link Control) layer of a main cell, distributing one path to an RLC layer of an auxiliary cell, respectively marking a first mark and a second mark on the downlink data scheduled to an MAC (Media Access Control) layer on the RLC layer, and sending the data packet marked with the first mark to the MAC layer of the primary cell, and sending the data packet marked with the second mark to the MAC layer of the secondary cell. According to the invention, the problem of packet disorder caused by carrier aggregation shunting of the PDCP layer and the RLC layer can be effectively reduced. The method can be widely applied to the technical field of carrier aggregation.

Description

Technical Field

[0001] The present invention relates to the technical field of carrier aggregation, and in particular to a carrier aggregation downlink data offloading method. Background Art

[0002] In the existing carrier aggregation data downlink process, the RLC layer of the primary cell determines the amount of data that the carrier aggregation bears and allocates to the RLC layer buffer area of ​​the primary cell and the secondary cell, and sends the amount of data allocated to the RLC layer buffer area of ​​the secondary cell to the MAC layer of the secondary cell. Next, the RLC layer of the primary cell determines the amount of data requested from the primary cell side to the RLC layer of the primary cell, and the amount of data requested from the secondary cell side to the RLC layer of the primary cell. Then, the RLC layer of the primary cell allocates data according to the amount of data requested by the primary cell side and the secondary cell side, and composes the allocated data into RLC PDUs and sends them to the MAC layer of the primary cell and the MAC layer of the secondary cell respectively.

[0003] In the above process, when the RLC layer data of the primary cell is sent to the MAC layer for real-time scheduling, the data packets to be scheduled to the MAC layer of the secondary cell may be distributed to the MAC layer of the primary cell, resulting in the sequence numbers of the data packets scheduled to the MAC layer of the primary cell being 1, 3, 5, 7, and the sequence numbers of the data packets scheduled to the MAC layer of the secondary cell being 2, 4, 6, 8, which are out of order. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present invention is to provide a carrier aggregation downlink data offloading method, which can avoid the technical problem of data disorder at the MAC layer when scheduling downlink data from the RLC layer to the MAC layer.

[0005] The technical solution adopted by the present invention is: In a first aspect, the present invention provides a carrier aggregation downlink data diversion method, the method comprising: according to the bandwidth of the primary and secondary cells and the UE scheduling capability, the PDCP layer of the primary cell diverts the downlink data, one way is diverted to the RLC layer of the primary cell, and the other way is diverted to the RLC layer of the secondary cell, wherein the downlink data is sorted in the diversion process to form data packets with sequence numbers in order, and the RLC layer of the primary cell and the RLC layer of the secondary cell have a shared memory; when the first data packet of the RLC layer of the primary cell is scheduled to the MAC layer of the primary cell, the RLC layer of the primary cell determines whether the first data packet is to be scheduled by the secondary cell data packet, if yes, skip the first data packet and send a message to the secondary cell; if not, mark the first data packet with a first mark, and subsequently send the first data packet marked with the first mark to the MAC layer of the primary cell; when scheduling the second data packet of the RLC layer of the secondary cell to the MAC layer of the secondary cell, the RLC layer of the secondary cell determines whether the second data packet is the data packet to be scheduled by the primary cell, and if yes, skip the second data packet and send a message to the primary cell; if not, mark the second data packet with a second mark, and subsequently send the second data packet marked with the second mark to the MAC layer of the secondary cell.

[0006] The beneficial effects of the present invention are: The present invention uses a shared memory for the RLC layer of the primary cell and the RLC layer of the secondary cell. When scheduling downlink data from the shared memory to the MAC layer of the secondary cell, the packets to be subsequently scheduled in the primary cell are marked with the first tag. When real-time scheduling is performed, scheduling is started from the marked data packets. This ensures that the SN numbers of the data packets scheduled to the MAC layer of the primary cell are continuous 1, 2, 3, 4, and the SN numbers of the data packets scheduled to the MAC layer of the secondary cell are continuous 5, 6, 7, 8. In this way, the packet disorder problem caused by carrier aggregation and shunting at the RLC layer can be effectively reduced.

[0007] At the same time, the present invention also solves the disorder problem caused by the PDCP layer diversion. Downlink data is aggregated at the RLC layer, which can solve the disorder problem of the PDCP layer. Subsequently, the amount of data sent by the PDCP layer can be scheduled to the MAC layer at one time. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a flow chart of an embodiment of a carrier aggregation downlink data offloading method of the present invention; Figure 2 It is a structural schematic diagram of an embodiment of a carrier aggregation downlink data offloading method of the present invention. DETAILED DESCRIPTION

[0009] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0010] Please also read Figure 1 and Figure 2 .like Figure 1 As shown, the method comprises the following steps: S11: According to the bandwidth of the primary and secondary cells and the UE scheduling capability, the PDCP layer of the primary cell splits the downlink data, one way is split to the RLC layer of the primary cell, and the other way is split to the RLC layer of the secondary cell, wherein the downlink data is sorted in the splitting process to form data packets with sequence numbers in a sequential order, and the RLC layer of the primary cell and the RLC layer of the secondary cell have a shared memory; like Figure 2 As shown in the figure, the downlink data is sent from NG (5G core network) or S1 (4G core network) to the PDCP layer, and the PDCP layer divides the downlink data into two paths, one to the primary cell RLC layer and the other to the secondary cell RLC layer.

[0011] The diversion method includes at least three methods, which are as follows: First, the default ratio is 1:1 splitting, that is, data packets with odd sequence numbers are sent to the RLC layer of the primary cell, and data packets with even sequence numbers are sent to the RLC layer of the secondary cell.

[0012] Second, configure the ratio split. That is, send m data packets with sequence numbers from 0 to m-1 to the RLC layer of the primary cell; the secondary cell sends n data packets with sequence numbers from m to m+n to the RLC layer of the secondary cell, and the total number of packets is m+n. When m=n, it is equivalent to 1:1 split.

[0013] Third, traffic is split according to bandwidth capacity. If the bandwidth of the primary cell is 100M and the bandwidth of the secondary cell is 60M, traffic is split according to 100:60 or 50:30.

[0014] The data packets that are in sequence at the PDCP layer will have disordered sequence numbers received by the RLC layer after diversion; then, the downlink data continues to be aggregated at the RLC layer. Because the RLC layer has a cache, the data packets sent by the PDCP layer after a period of time will be saved in the cache chain corresponding to the RLC layer according to the SN (sequence number), which is equivalent to sorting.

[0015] It should be noted here that the RLC layer of the primary cell and the RLC layer of the secondary cell use shared memory, so that the RLC layer has only one data cache chain, and the scheduling of the MAC layer of the primary and secondary cells can be seen and scheduled to the corresponding layer of the opposite UE for processing.

[0016] S12: When scheduling the first data packet of the RLC layer of the primary cell to the MAC layer of the primary cell, the RLC layer of the primary cell determines whether the first data packet is a data packet to be scheduled by the secondary cell. If yes, the first data packet is skipped and a message is sent to the secondary cell; if no, the first data packet is marked with a first mark, and the first data packet marked with the first mark is subsequently sent to the MAC layer of the primary cell; S13: When the second data packet of the RLC layer of the secondary cell is scheduled to the MAC layer of the secondary cell, the RLC layer of the secondary cell determines whether the second data packet is the data packet to be scheduled by the primary cell. If so, the second data packet is skipped and a message is sent to the primary cell; if not, the second data packet is marked with a second mark, and the second data packet marked with the second mark is subsequently sent to the MAC layer of the secondary cell.

[0017] Step S12 and step S13 are parallel steps, and their order can be swapped.

[0018] Since the RLC layer of the primary cell and the RLC layer of the secondary cell use a shared memory, the contents of the first data packet and the second data packet are the same.

[0019] It should be noted that the first mark and the second mark are different. For example, the first mark is set to pcellSched=1, and the second mark is set to scellSched=1.

[0020] When subsequently packetizing, the first mark, the second mark and the sequence number of the data packet are combined to packetize in order. If the data scheduled to the primary cell is packetized, the data packets with the first mark are packetized in the sequence number order. If the data scheduled to the secondary cell is packetized, the data packets with the second mark are packetized in the sequence number order.

[0021] When retransmitting (transferring data from the main RLC layer to the MAC layer), the retransmission is carried out according to the protocol, and the retransmission sn number can also be guaranteed to be continuous.

[0022] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A carrier aggregation downlink data offloading method, characterized in that: include: According to the bandwidth of the primary and secondary cells and the UE scheduling capability, the PDCP layer of the primary cell splits the downlink data, one way is split to the RLC layer of the primary cell, and the other way is split to the RLC layer of the secondary cell, wherein the downlink data is sorted in the splitting process to form data packets with sequence numbers in a sequential order, and the RLC layer of the primary cell and the RLC layer of the secondary cell have a shared memory; When scheduling a first data packet of the RLC layer of the primary cell to the MAC layer of the primary cell, the RLC layer of the primary cell determines whether the first data packet is a data packet to be scheduled by the secondary cell, and if so, skips the first data packet and sends a message to the secondary cell; if not, marks the first data packet with a first mark, and subsequently sends the first data packet marked with the first mark to the MAC layer of the primary cell; When scheduling the second data packet of the RLC layer of the secondary cell to the MAC layer of the secondary cell, the RLC layer of the secondary cell determines whether the second data packet is the data packet to be scheduled by the primary cell. If so, the second data packet is skipped and a message is sent to the primary cell; if not, the second data packet is marked with a second mark, and the second data packet marked with the second mark is subsequently sent to the MAC layer of the secondary cell.

Images