Efficient 5G Dual-Connection Separate Bearer Data Transmission Method and System

Abstract

The present invention provides an efficient method and system for data transmission of 5G dual-connection split bearers, including: Step S1: Establish a dual-connection split bearer and initialize the state coefficients of the primary RLC entity and the secondary RLC entity; Step S2: Upon receiving a data transmission request, process the data to be transmitted and place it in the send queue; Step S3: Perform data split transmission; Step S4: The primary and secondary RLC entities process and send the data to be sent, and each reports the status of the logical channel to the PDCP entity; Step S5: Perform transmission status analysis. If there is a preset situation, perform data recovery and transfer transmission. The present invention reduces the packet reordering delay of the PDCP at the receiving end and reduces the service delay; by detecting the transmission status and buffer status of the logical channel, the data to be transmitted is reasonably split and transmitted, thereby reducing the data transmission delay, further reducing the PDCP reordering delay at the receiving end, and thus overall reducing the service delay and improving the service quality.

Description

Technical Field

[0001] The present invention relates to the field of data transmission, and more specifically, to an efficient 5G dual-connection split bearer data transmission method and system. Background Art

[0002] 5G dual-connection (NR-DC, NR-NR Dual-Connection) is an important technology introduced in the 3GPP Release 15 version and refined in the 3GPP Release 16 version. Through the dual-connection technology, the 5G master base station and the 5G secondary base station can use the non-ideal backhaul Xn interface to achieve multi-carrier transmission, thereby improving the terminal throughput and data transmission reliability. (As shown in the attached Figure 1 )

[0003] Three types of bearers are defined in 5G dual-connection: MCG bearer, SCG bearer, and Split bearer. The MCG bearer is a bearer that only transmits data through the master base station; the SCG bearer is a bearer that only transmits data through the secondary base station; the Split bearer is a bearer that transmits data through both the master base station and the secondary base station at the same time. (As shown in Figure 2 of the attached drawings)

[0004] The data of the split bearer is separated at the PDCP layer. That is, in the same transmission direction, each PDCP entity of the split bearer is associated with 2 RLC entities, one of which is the primary RLC entity (Primary RLC entity), and the other is the split secondary RLC entity (Split Secondary RLC entity). The split bearer is divided into two transmission modes, one is the replication mode, and the other is the splitting mode, and only one transmission mode can be activated at the same time. The replication mode means that the same data is replicated and transmitted on the primary RLC entity and the split secondary RLC entity; the splitting mode means that when the current data volume is large, the user data is selectively split and transmitted on the primary RLC entity and the split secondary RLC entity. The PDCP entity of the split bearer determines whether to perform split transmission by comparing the total amount of data to be sent with the split threshold (ul-DataSplitThreshold). If the total amount of data to be sent does not reach the threshold, the data is only transmitted through the primary RLC entity, otherwise the data can be transmitted simultaneously on the primary RLC entity and the split secondary RLC entity to perform data split transmission, thereby improving the transmission efficiency. For the split bearer, the received data packets may be out of order, so the data of the split bearer is reordered at the PDCP layer.

[0005] The relevant content of the transmission operation of the 3GPP protocol and the SDU discarding procedure is described in Section 5.2.1 Transmit operation of 3GPP TS 38.323-g10 and Section 5.4 of 3GPP TS 38.322-g10. It is described in this document that: submit the PDCP PDU to either the primary RLC entity or the split secondary RLC entity; however, the standard does not describe in detail how to split the flow. This method adopts an optimized splitting strategy to improve the service quality of the service;. It is described in the document that: If the transmitting PDCP entity is associated with two RLC entities, the UE should minimize the amount of PDCP PDUs submitted to lower layers before receiving request from lower layers and minimize the PDCP SN gap between PDCP PDUs submitted to two associated RLC entities to minimize PDCP reordering delay in the receiving PDCP entity. And this method adopts an optimized splitting strategy, which can reduce the PDCP SN GAP.

[0006] Patent document CN111132233B (application number: CN201811287597.7) discloses a control method for split bearers and related devices. The control method for split bearers includes: the terminal is configured with a target split bearer, and the target split bearer includes N transmission paths, where N is a positive integer greater than 2; determining an available transmission path set from the N transmission paths based on the amount of uplink data to be transmitted and the split bearer threshold of the target split bearer, where the available transmission path set is: the N transmission paths, or a transmission path set associated with the split bearer threshold; and performing uplink data transmission through a target transmission path in the available transmission path set. However, this invention does not have a flexible detection logic for the transmission status and buffer status of the logical channel, and the mitigation of data transmission delay is insufficient. Summary of the Invention

[0007] Aiming at the defects in the prior art, the purpose of the present invention is to provide an efficient 5G dual-connection split bearer data transmission method and system.

[0008] An efficient 5G dual-connection split bearer data transmission method provided by the present invention includes:

[0009] Step S1: Establish a dual-connection split bearer, and initialize the state coefficients of the primary RLC entity and the secondary RLC entity;

[0010] Step S2: Upon receiving a data transmission request, process the data to be transmitted and place it in the send queue;

[0011] Step S3: Perform data split transmission;

[0012] Step S4: The primary and secondary RLC entities process and send the data to be sent, and each reports the status of the logical channel to the PDCP entity;

[0013] Step S5: Perform transmission status analysis. If a preset situation exists, perform data recovery and transfer transmission.

[0014] Preferably, by monitoring and comparing the data buffer volume status and transmission status of the logical channels of the primary and secondary RLC entities, the data to be transmitted is reasonably split. The amount of data split by the logical channel cannot exceed the remaining space in the buffer. If the buffer is full, no data is sent to the logical channel of this path;

[0015] The data buffer volume status refers to the ratio of the amount of data to be transmitted to the total amount of data that can be buffered in the buffer;

[0016] The transmission status refers to the state of data transmission, and the air interface data transmission rate and transmission error packet rate are used as the status indicators of this state.

[0017] Preferably, in the said Step S1:

[0018] Initialize the transmission status coefficients of the logical channels of the primary RLC entity and the secondary RLC entity to 1 and the buffer status to empty;

[0019] The factors determined by the weighted transmission status coefficients of the logical channels include:

[0020] The average transmission rate on this logical channel over a period of time, which consists of one or several transmission intervals. The higher the average transmission rate, the higher the corresponding transmission status coefficient; if the average transmission rate is 0, the transmission status coefficient is 0;

[0021] For the AM RLC transmission entity, the amount of data that can be transmitted in the send window. If the data that has been transmitted has not received an acknowledgment from the receiving end, the amount of data that can be transmitted in the send window will become smaller until the send window is congested. The more congested the send window is, the lower the corresponding transmission status coefficient. If the send window is completely congested, the transmission status coefficient is 0;

[0022] For the AM RLC transmission entity, the packet error rate of data transmission reflects the channel quality. The packet error rate is statistically calculated based on the number of unacknowledged packets in the status report sent by the receiving end. The lower the packet error rate, the higher the corresponding transmission status coefficient.

[0023] Preferably, in the step S2:

[0024] PDCP receives a user data transmission request from the upper layer, processes the data to be transmitted through the protocol, and then puts it into the transmission queue.

[0025] In the step S3:

[0026] If the amount of data to be sent does not exceed the splitting threshold, it is sent on the primary RLC entity; if the amount of data to be sent exceeds the splitting threshold, PDCP compares the transmission status coefficients on the logical channels of the primary and secondary RLC entities, and distributes the user data to be transmitted proportionally. The amount of data sent to RLC does not exceed the available space in the RLC buffer.

[0027] The splitting threshold is configured by the base station for the terminal to control whether to enable the splitting function. If the amount of data is small and does not exceed the splitting threshold, there is no need to enable the splitting transmission function.

[0028] The logic of proportional distribution:

[0029] If the transmission status coefficient value of the logical channel of any one of the primary and secondary RLC entities is 0, no data to be transmitted is sent to this RLC entity.

[0030] If the transmission status coefficient values of the logical channels of the primary and secondary RLC entities are both non-zero, the amount of data sent on the corresponding logical channel of the RLC entity is as follows:

[0031] The amount of data transmitted on the logical channel of this RLC entity = the total amount of data to be transmitted * the transmission status coefficient of the logical channel of this RLC entity / the sum of the transmission status coefficients of the logical channels of the primary and secondary RLC entities.

[0032] Preferably, in the step S4:

[0033] The primary and secondary RLC entities process and send the data to be sent according to the 3GPP protocol.

[0034] The primary and secondary RLC entities respectively report the transmission status and buffer status of their own logical channels to the PDCP entity.

[0035] In the step S5:

[0036] PDCP performs transmission status analysis. If the coefficient of sending one logical channel is less than a preset value and the coefficient of another logical channel is greater than a preset value, part or all of the to-be-sent data on the logical channel with the coefficient less than the preset value will be transferred to the logical channel with the coefficient greater than the preset value for transmission. The amount of data sent to RLC does not exceed the free space in the RLC buffer.

[0037] Whether partial or full transfer is determined by the transmission state coefficient. A transmission state coefficient of 0 means that data can no longer be transmitted and all data is transferred. A non-zero transmission state coefficient means that data can still be transmitted, but the transmission efficiency is reduced and part of the data is transferred. The amount of data transferred = total cached data amount * (1-transmission state coefficient).

[0038] An efficient 5G dual-connection split bearer data transmission system provided by the present invention includes:

[0039] Module M1: establishes dual-connection split bearer and initializes the state coefficients of the primary RLC entity and the secondary RLC entity;

[0040] Module M2: receives a data transmission request, processes the data to be transmitted, and puts it into the sending queue;

[0041] Module M3: performs data diversion and transmission;

[0042] Module M4: The primary and secondary RLC entities process and send data to be sent, and each reports the status of the logical channel to the PDCP entity;

[0043] Module M5: Analyze the transmission status. If there is a preset situation, recover and transfer the data.

[0044] Preferably, the data to be transmitted is reasonably distributed by monitoring and comparing the data buffer status and transmission status of the primary and secondary RLC entity logical channels. The amount of data distributed to the logical channel cannot exceed the free space in the buffer area. If the buffer area is full, no data will be sent to the logical channel of the path.

[0045] The data cache capacity status refers to the ratio of the amount of data to be transmitted to the total amount of data that can be cached in the cache area;

[0046] The transmission status refers to the status of data transmission, with the air interface data transmission rate and transmission packet error rate as the status indicators.

[0047] Preferably, in the module M1:

[0048] Initialize the transmission state coefficient of the primary RLC entity and the secondary RLC entity logical channel to 1 and the buffer state to empty;

[0049] The factors that determine the weighting of the transmission status coefficient of the logical channel include:

[0050] The average transmission rate on this logical channel over a period of time, which is composed of one or several transmission intervals. The higher the average transmission rate, the higher the corresponding transmission state coefficient; when the average transmission rate is 0, the transmission state coefficient is 0.

[0051] For the AM RLC transmission entity, the amount of data that can be transmitted in the transmission window. If the transmitted data has not been acknowledged by the receiving end, the amount of data that can be transmitted in the transmission window will become smaller until the transmission window is congested. The more congested the transmission window is, the lower the corresponding transmission state coefficient. If the transmission window is completely congested, the transmission state coefficient is 0.

[0052] For the AM RLC transmission entity, the packet error rate of data transmission. The packet error rate reflects the channel quality and is statistically calculated from the number of unacknowledged packets in the status report sent by the receiving end. The lower the packet error rate, the higher the corresponding transmission state coefficient.

[0053] Preferably, in the module M2:

[0054] PDCP receives a user data transmission request from the upper layer, processes the data to be transmitted through the protocol, and puts it into the transmission queue.

[0055] In the module M3:

[0056] If the amount of data to be sent does not exceed the splitting threshold, it is sent on the primary RLC entity; if the amount of data to be sent exceeds the splitting threshold, PDCP compares the transmission state coefficients on the logical channels of the primary and secondary RLC entities, and distributes the user data to be transmitted proportionally. The amount of data sent to the RLC does not exceed the available space in the RLC buffer.

[0057] The splitting threshold is configured by the base station for the terminal to control whether to enable the splitting function. If the amount of data is small and does not exceed the splitting threshold, there is no need to enable the splitting transmission function.

[0058] The logic of proportional distribution:

[0059] If the transmission state coefficient value of the logical channel of any one of the primary and secondary RLC entities is 0, no data to be transmitted is sent to this RLC entity.

[0060] If the transmission state coefficient values of the logical channels of the primary and secondary RLC entities are both non-zero, the amount of data sent on the logical channel of the corresponding RLC entity is as follows:

[0061] The amount of data transmitted on the logical channel of this RLC entity = the total amount of data to be transmitted * the transmission state coefficient of the logical channel of this RLC entity / the sum of the transmission state coefficients of the logical channels of the primary and secondary RLC entities.

[0062] Preferably, in the module M4:

[0063] The primary and secondary RLC entities process and send the data to be sent according to the 3GPP protocol;

[0064] The primary and secondary RLC entities respectively report the transmission status and buffer status of their own logical channels to the PDCP entity;

[0065] In the module M5:

[0066] The PDCP performs transmission status analysis. If the coefficient of one of the logical channels for transmission is less than the preset value and the coefficient of the other logical channel is greater than the preset value, then part or all of the data to be sent on the logical channel with the coefficient less than the preset value is transferred to the logical channel with the coefficient greater than the preset value for transmission, and the amount of data sent to the RLC does not exceed the available space in the RLC buffer;

[0067] Whether to transfer part or all of the data is determined according to the transmission status coefficient. A transmission status coefficient of 0 means that data cannot be transmitted anymore, and all data is transferred; a non - zero transmission status coefficient means that data can still be transmitted, but the transmission efficiency has decreased, and part of the data is transferred. The amount of transferred data = total buffer data volume * (1 - transmission status coefficient).

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] 1. The present invention reduces the packet re - ordering delay of the receiving - end PDCP and reduces the service delay; by detecting the transmission status and buffer status of the logical channels, the data to be transmitted is reasonably split and transmitted, thereby reducing the data transmission delay, further reducing the receiving - end PDCP re - ordering delay, and thus overall reducing the service delay and improving the service quality.

[0070] 2. The present invention reduces data packet loss and guarantees the service quality of the service; it can flexibly transfer data to the logical channel with higher transmission efficiency for transmission, try to ensure that data packets can be normally transmitted, reduce the packet loss phenomenon, reduce the transmission delay, and guarantee the service quality of the service. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] By reading the following detailed description of the non - restrictive embodiments with reference to the accompanying drawings, other features, objects, and advantages of the present invention will become more apparent:

[0072] Figure 1 It is a schematic diagram of the 5G dual - connection scenario;

[0073] Figure 2 It is a system architecture diagram of 5G dual - connection;

[0074] Figure 3 It is the 5G dual - connection split - bearer split - flow processing process;

[0075] Figure 4 It is a solution for realizing traffic splitting of 5G dual - connection split bearers. Specific implementation manners

[0076] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all fall within the protection scope of the present invention.

[0077] Example 1:

[0078] According to an efficient 5G dual - connection split bearer data transmission method provided by the present invention, as Figures 1 - 4 shown, it includes:

[0079] Step S1: Establish a dual - connection split bearer, and initialize the state coefficients of the primary RLC entity and the secondary RLC entity;

[0080] Step S2: When receiving a data transmission request, process the data to be transmitted and put it into the sending queue;

[0081] Step S3: Perform data traffic splitting transmission;

[0082] Step S4: The primary and secondary RLC entities process and send the data to be sent, and each reports the status of the logical channel to the PDCP entity;

[0083] Step S5: Perform transmission status analysis. If there is a preset situation, perform data recovery and transfer transmission.

[0084] Specifically, by monitoring and comparing the data buffer volume status and transmission status of the logical channels of the primary and secondary RLC entities, the data to be transmitted is reasonably split. The data volume split by the logical channel cannot exceed the available space in the buffer. If the buffer is full, no data will be sent to the logical channel of this path;

[0085] The data buffer volume status refers to the ratio of the data volume to be transmitted and the total data volume that can be cached in the buffer;

[0086] The transmission status refers to the state of data transmission, and the air - interface data transmission rate and transmission error packet rate are used as the status indicators for this state.

[0087] Specifically, in the step S1:

[0088] Initialize the transmission status coefficients of the logical channels of the primary RLC entity and the secondary RLC entity to 1 and the buffer status to empty;

[0089] The factors determined by the weighted transmission status coefficients of the logical channels include:

[0090] The average transmission rate on this logical channel over a period of time, which consists of one or several transmission intervals. The higher the average transmission rate, the higher the corresponding transmission state coefficient; when the average transmission rate is 0, the transmission state coefficient is 0.

[0091] For the AM RLC transmission entity, the amount of data that can be transmitted in the transmission window. If the transmitted data has not been acknowledged by the receiving end, the amount of data that can be transmitted in the transmission window will become smaller until the transmission window is congested. The more congested the transmission window is, the lower the corresponding transmission state coefficient. If the transmission window is completely congested, the transmission state coefficient is 0.

[0092] For the AM RLC transmission entity, the packet error rate of data transmission. The packet error rate reflects the channel quality and is statistically calculated from the number of unacknowledged packets in the status report sent by the receiving end. The lower the packet error rate, the higher the corresponding transmission state coefficient.

[0093] Specifically, in the step S2:

[0094] PDCP receives a user data transmission request from the upper layer, processes the data to be transmitted through the protocol and puts it into the transmission queue.

[0095] In the step S3:

[0096] If the amount of data to be transmitted does not exceed the splitting threshold, it is transmitted on the primary RLC entity; if the amount of data to be transmitted exceeds the splitting threshold, PDCP compares the transmission state coefficients on the logical channels of the primary and secondary RLC entities, and distributes the user data to be transmitted proportionally. The amount of data sent to the RLC does not exceed the available space in the RLC buffer.

[0097] The splitting threshold is configured by the base station to the terminal to control whether to enable the splitting function. If the amount of data is small and does not exceed the splitting threshold, there is no need to enable the splitting transmission function.

[0098] The logic of proportional distribution:

[0099] If the transmission state coefficient value of the logical channel of any one of the primary and secondary RLC entities is 0, no data to be transmitted is sent to this RLC entity.

[0100] If the transmission state coefficient values of the logical channels of the primary and secondary RLC entities are both non-zero, the amount of data transmitted on the logical channel of the corresponding RLC entity is as follows:

[0101] The amount of data transmitted on the logical channel of this RLC entity = the total amount of data to be transmitted * the transmission state coefficient of the logical channel of this RLC entity / the sum of the transmission state coefficients of the logical channels of the primary and secondary RLC entities.

[0102] Specifically, in the step S4:

[0103] The primary and secondary RLC entities process and send the data to be sent according to the 3GPP protocol;

[0104] The primary and secondary RLC entities respectively report the transmission status and buffer status of their logical channels to the PDCP entity;

[0105] In the step S5:

[0106] The PDCP performs transmission status analysis. If the coefficient of one of the logical channels to be sent is less than the preset value and the coefficient of the other logical channel is greater than the preset value, then part or all of the data to be sent on the logical channel with the coefficient less than the preset value is transferred to the logical channel with the coefficient greater than the preset value for sending, and the amount of data sent to the RLC does not exceed the available space in the RLC buffer;

[0107] Whether to transfer part or all of the data is determined according to the transmission status coefficient. A transmission status coefficient of 0 means that data cannot be transmitted anymore, and all data is transferred; a non-zero transmission status coefficient means that data can still be transmitted, but the transmission efficiency has decreased, and part of the data is transferred. The amount of transferred data = total buffered data volume * (1 - transmission status coefficient).

[0108] Example 2:

[0109] Embodiment 2 is a preferred example of Embodiment 1 to more specifically illustrate the present invention.

[0110] Those skilled in the art can understand an efficient 5G dual-connection split bearer data transmission method provided by the present invention as a specific implementation manner of an efficient 5G dual-connection split bearer data transmission system. That is, the efficient 5G dual-connection split bearer data transmission system can be implemented by executing the step process of the efficient 5G dual-connection split bearer data transmission method.

[0111] An efficient 5G dual-connection split bearer data transmission system provided by the present invention includes:

[0112] Module M1: Establish a dual-connection split bearer and initialize the status coefficients of the primary RLC entity and the secondary RLC entity;

[0113] Module M2: Receive a data transmission request, process the data to be transmitted and put it into the send queue;

[0114] Module M3: Perform data split transmission;

[0115] Module M4: The primary and secondary RLC entities process and send the data to be sent, and respectively report the status of the logical channels to the PDCP entity;

[0116] Module M5: Analyze the transmission status. If there is a preset situation, perform data recovery and transfer transmission.

[0117] Specifically, by monitoring and comparing the data buffer status and transmission status of the primary and secondary RLC entity logical channels, reasonably divert the data to be transmitted. The amount of data diverted by the logical channel cannot exceed the remaining space in the buffer. If the buffer is full, no data will be sent to the logical channel of this path.

[0118] The data buffer status refers to the ratio of the amount of data to be transmitted to the total amount of data that can be cached in the buffer.

[0119] The transmission status refers to the status of data transmission, and the air interface data transmission rate and transmission error packet rate are used as the status indicators.

[0120] Specifically, in the module M1:

[0121] Initialize the transmission status coefficients of the primary and secondary RLC entity logical channels to 1 and the buffer status to empty.

[0122] The factors determined by weighting the transmission status coefficients of the logical channels include:

[0123] The average transmission rate on this logical channel over a period of time, which consists of one or several transmission intervals. The higher the average transmission rate, the higher the corresponding transmission status coefficient; if the average transmission rate is 0, the transmission status coefficient is 0.

[0124] For the AM RLC sending entity, the amount of data that can be sent in the sending window. If the data that has been sent has not received an acknowledgment from the receiving end, the amount of data that can be sent in the sending window will become smaller until the sending window is congested. The more congested the sending window is, the lower the corresponding transmission status coefficient. If the sending window is completely congested, the transmission status coefficient is 0.

[0125] For the AM RLC sending entity, the error packet rate of data transmission. The error packet rate reflects the channel quality and is statistically calculated from the unacknowledged numbers in the status report sent by the receiving end. The lower the error packet rate, the higher the corresponding transmission status coefficient.

[0126] Specifically, in the module M2:

[0127] PDCP receives a user data transmission request from the upper layer, processes the data to be transmitted through the protocol, and puts it into the sending queue.

[0128] In the module M3:

[0129] If the amount of data to be sent does not exceed the splitting threshold, it is sent on the primary RLC entity; if the amount of data to be sent exceeds the splitting threshold, the PDCP allocates the user data to be transmitted proportionally by comparing the transmission state coefficients on the logical channels of the primary and secondary RLC entities, and the amount of data sent to the RLC does not exceed the available space in the RLC buffer.

[0130] The splitting threshold is configured by the base station for the terminal to control whether to enable the splitting function. If the amount of data is small and does not exceed the splitting threshold, there is no need to enable the splitting transmission function.

[0131] The logic of proportional allocation:

[0132] If the transmission state coefficient value of the logical channel of any one of the primary and secondary RLC entities is 0, no data to be transmitted is sent to this RLC entity.

[0133] If the transmission state coefficient values of the logical channels of the primary and secondary RLC entities are both non-zero, the amount of data sent on the corresponding logical channel of the RLC entity is as follows:

[0134] The amount of data transmitted on the logical channel of this RLC entity = the total amount of data to be transmitted * the transmission state coefficient of the logical channel of this RLC entity / the sum of the transmission state coefficients of the logical channels of the primary and secondary RLC entities.

[0135] Specifically, in the module M4:

[0136] The primary and secondary RLC entities process and send the data to be sent according to the 3GPP protocol.

[0137] The primary and secondary RLC entities each report the transmission state and buffer state of their own logical channels to the PDCP entity.

[0138] In the module M5:

[0139] The PDCP performs transmission state analysis. If the coefficient of one of the logical channels to be sent is less than the preset value and the coefficient of the other logical channel is greater than the preset value, then part or all of the data to be sent on the logical channel with the coefficient less than the preset value is transferred to the logical channel with the coefficient greater than the preset value for sending, and the amount of data sent to the RLC does not exceed the available space in the RLC buffer.

[0140] Whether to transfer part or all is determined by the transmission state coefficient. A transmission state coefficient of 0 means that data cannot be transmitted anymore, and all data is transferred; a non-zero transmission state coefficient means that data can still be transmitted, but the transmission efficiency has decreased, and part of the data is transferred. The amount of data transferred = the total amount of cached data * (1 - the transmission state coefficient).

[0141] Example 3:

[0142] Embodiment 3 is a preferred example of Embodiment 1 to illustrate the present invention more specifically.

[0143] For the scenario of split bearer shunt transmission mode, the 3GPP standard defines a simple shunt strategy, that is, to determine whether to perform shunt transmission through the split threshold (ul-DataSplitThreshold), but does not clearly specify the specific shunt traffic. And this method dynamically allocates data traffic by monitoring the transmission status of logical channels on different paths, enabling service data to be transmitted to the peer end more quickly, reducing data transmission delay, and minimizing the SN gap of PDCP, reducing the PDCP reordering delay at the receiving end, and ensuring service quality.

[0144] In addition, for the scenario of split bearer shunt transmission mode, when the transmission on the logical channel of a certain path is abnormal (such as weak signal, network congestion, etc.), the data on this logical channel cannot be transmitted to the receiving end on time. According to the 3GPP regulations, these pending data will be discarded after the discard timer expires, which will affect service continuity or cause service anomalies. This method monitors the transmission status of the logical channel and the buffer status. When it detects that the transmission of the logical channel on a certain path is slow or abnormal, it can timely transfer the pending data on this path to the logical channel of another path for transmission, thus ensuring the normal transmission of data packets, reducing packet loss and transmission delay, improving the transmission efficiency and reliability of data, ensuring normal services, and enhancing the user experience.

[0145] In the NR dual-connection function defined by the 3GPP R16 standard, for split bearer, in the same transmission direction, each PDCP entity is associated with 2 RLC entities, one of which is the primary RLC entity (Primary RLC entity), and the other is the split secondary RLC entity (Split Secondary RLC entity). When sending data, the PDCP entity determines on which RLC entities to transmit data by comparing the total amount of data to be sent with the split threshold (ul-DataSplitThreshold). If the total amount of data to be sent does not reach the threshold, the data is only transmitted through the primary RLC entity; otherwise, the data is transmitted through both the primary RLC entity and the split secondary RLC entity simultaneously for split transmission. However, for the scenario of split transmission, when a certain RLC entity has a transmission anomaly due to certain reasons (such as poor signal, network congestion, etc.), it may cause the discard timer of the pending data packets on this path to expire. According to the 3GPP standard regulations, these pending data packets should be discarded, which will affect normal services.

[0146] This method innovatively improves the shunt data transmission mechanism. By detecting the data transmission efficiency of each logical channel, when it is detected that a certain logical channel is transmitting slowly or abnormally, within the allowable range of the discard timer, the data to be transmitted is timely shunted or transferred to the logical channel of another path for transmission, thereby ensuring the normal transmission of data packets, reducing packet loss and transmission delay, improving the data transmission efficiency and reliability, ensuring the normal operation of services, and enhancing the user experience.

[0147] Example 4:

[0148] Embodiment 4 is a preferred example of Embodiment 1 to more specifically illustrate the present invention.

[0149] This method reasonably shunts the data to be transmitted by monitoring and comparing the data buffer status and transmission status of the logical channels of the primary and secondary RLC entities. The amount of shunted data for the logical channel cannot exceed the available space in the buffer. If the buffer is full, no more data will be sent to the logical channel of this path.

[0150] The data buffer status refers to the ratio of the amount of data to be transmitted to the total amount of data that can be buffered in the buffer.

[0151] The transmission status refers to the state of data transmission, usually using the air interface data transmission rate and the transmission error packet rate as the state indicators.

[0152] The transmission status coefficient of the logical channel is determined by the following (not limited to) factors weighted:

[0153] 1. The average transmission rate of this logical channel in a recent period of time. This period of time can be composed of one or several transmission intervals (TTI). The higher the average transmission rate, the higher the corresponding transmission status coefficient. If the average transmission rate is 0, the transmission status coefficient is 0.

[0154] 2. For the AM RLC transmission entity, the amount of data that can be transmitted in the transmission window. If the transmitted data has not received an acknowledgment from the receiving end, the amount of data that can be transmitted in the transmission window will become smaller until the transmission window becomes congested. The more congested the transmission window, the lower the corresponding transmission status coefficient. If the transmission window is completely congested, the transmission status coefficient is 0.

[0155] 3. For the AM RLC transmission entity, the error packet rate of data transmission. The error packet rate reflects the channel quality to a certain extent. This error packet rate can be statistically calculated from the number of unacknowledged packets in the status report sent by the receiving end. The lower the error packet rate, the higher the corresponding transmission status coefficient.

[0156] The processing flow of this method is as shown in the appendix Figure 3 as follows. The process description is as follows:

[0157] Step 1: Establish a dual-connected split bearer, and initialize the transmission status coefficient (set to 1) and buffer status (empty) of the logical channels of the primary RLC entity and the secondary RLC entity.

[0158] Step 2: PDCP receives a user data transmission request from the upper layer (SDAP), processes the data to be transmitted through the protocol, and puts it into the send queue.

[0159] Step 3: If the amount of data to be sent does not exceed the split threshold (ul-DataSplitThreshold), it is sent on the primary RLC entity; otherwise, PDCP allocates the user data to be transmitted proportionally by comparing the transmission status coefficients on the logical channels of the primary and secondary RLC entities. However, the amount of data sent to the RLC cannot exceed the available space in the RLC buffer.

[0160] The split threshold is configured by the base station for the terminal, and its function is to control whether the terminal enables the split function. If the amount of data is small, that is, it does not exceed the split threshold, there is no need to enable the split transmission function.

[0161] Logic for proportional allocation:

[0162] If the transmission status coefficient value of the logical channel of any one of the primary and secondary RLC entities is 0, no data to be transmitted is sent to that RLC entity.

[0163] If the transmission status coefficient values of the logical channels of both the primary and secondary RLC entities are non-zero, the amount of data sent on the corresponding logical channel of the RLC entity is calculated by the following formula:

[0164] The amount of data transmitted on the logical channel of this RLC entity = the total amount of data to be transmitted * the transmission status coefficient of the logical channel of this RLC entity / the sum of the transmission status coefficients of the logical channels of the primary and secondary RLC entities.

[0165] Step 4: The primary and secondary RLC entities process and send the data to be sent according to the 3GPP protocol.

[0166] Step 5: The primary and secondary RLC entities respectively report the transmission status and buffer status of their logical channels to the PDCP entity.

[0167] Step 6: PDCP performs transmission status analysis. If the transmission status of one of the logical channels is poor (for example, the coefficient is less than 0.3, this threshold can be configured), and the transmission status of the other logical channel is good (for example, the coefficient is greater than 0.7, this threshold can be configured), then part or all of the data to be sent on the logical channel with poor transmission status is transferred to the logical channel with good transmission status for sending. However, the amount of data sent to the RLC cannot exceed the available space in the RLC buffer.

[0168] Part or all of the transfer is determined according to the transmission status coefficient. For example, if the transmission status coefficient is 0, it means that data cannot be transmitted anymore, and all data will be transferred. If the transmission status coefficient is non-zero, it means that data can still be transmitted, but the transmission efficiency has decreased, and part of the data can be transferred (the amount of transferred data can be the total cached data volume * (1 - transmission status coefficient))

[0169] Step 7: Subsequently, the PDCP receives a user data transmission request from the upper layer (SDAP) and repeats the processing in Step 2.

[0170] Example 5:

[0171] Embodiment 5 is a preferred example of Embodiment 1 to more specifically illustrate the present invention.

[0172] This method does not modify the 3GPP standard, but adds corresponding split flow strategy analysis modules to the PDCP entity and the RLC entity.

[0173] 1. The RLC entity adds the calculation of the transmission status coefficient of the logical channel and regular reporting.

[0174] 2. The PDCP entity adds a split flow adjudication strategy and performs data split flow processing.

[0175] As shown in the appendix Figure 4 , after creating a dual-connection split bearer, the PDCP entity of the split bearer will be associated with 2 RLC entities, one primary RLC entity and the other secondary RLC entity. The primary and secondary RLC entities regularly report their respective transmission statuses to the PDCP according to the transmission status monitoring strategy described in the technical solution. The PDCP entity makes a split flow adjudication based on the data volume in the PDU queue and the transmission status of the primary and secondary RLC entities.

[0176] The implementation method is illustrated by scenarios as follows. Suppose the amount of data to be transmitted in the PDCP PDU queue has exceeded the splitting threshold (ul-DataSplitThreshold), and the transmission state coefficients of the logical channels of the primary and secondary RLC entities are both 1 at this time. Then the PDCP entity will evenly distribute the data to be transmitted to the two RLC entities for transmission. If subsequently, due to reasons such as signal weakening, the transmission quality of the transmission channel of the secondary RLC entity deteriorates, resulting in a decrease in the transmission rate and an increase in the packet error rate, and the data in the RLC SDU buffer area accumulates. At this time, the transmission state monitoring module of the secondary RLC entity reports the new transmission state to the PDCP entity after analysis. The splitting decision module of the PDCP entity transfers the data that has not been transmitted from the secondary RLC entity to the primary RLC entity for transmission after analysis, and also sends the user data received from the SDAP subsequently to the primary RLC entity for transmission. When the transmission quality of the transmission channel of the secondary RLC entity improves, the transmission state monitoring module of the secondary RLC entity reports the new transmission state to the PDCP entity, and the splitting decision module of the PDCP entity re-analyzes and resumes the normal transmission on the secondary path.

[0177] Those skilled in the art know that in addition to implementing the system, device and its various modules provided by the present invention in the form of pure computer-readable program code, the method steps can be logically programmed to enable the system, device and its various modules provided by the present invention to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. to achieve the same program. Therefore, the system, device and its various modules provided by the present invention can be regarded as a hardware component, and the modules included therein for implementing various programs can also be regarded as the structure within the hardware component; the modules for implementing various functions can also be regarded as either software programs for implementing the method or the structure within the hardware component.

[0178] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific implementation manners, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. An efficient 5G dual-connection split bearer data transmission method, characterized in that: include: Step S1: establishing a dual-connection split bearer and initializing the state coefficients of the primary RLC entity and the secondary RLC entity; Step S2: After receiving the data transmission request, the data to be transmitted is processed and placed into the sending queue; Step S3: performing data split transmission; In step S3: If the amount of data to be sent does not exceed the offload threshold, it is sent on the primary RLC entity. If the amount of data to be sent exceeds the offload threshold, PDCP compares the transmission status coefficients of the logical channels of the primary and secondary RLC entities and distributes the user data to be transmitted proportionally, so that the amount of data sent to RLC does not exceed the free space in the RLC buffer area. The offload threshold is configured by the base station to control whether the terminal can enable the offload function. If the data volume does not exceed the offload threshold, there is no need to enable the offload transmission function. Proportional allocation logic: If the transmission state coefficient value of any RLC entity logical channel in the primary and secondary RLC entities is 0, no data to be transmitted is sent to the RLC entity; If the transmission state coefficient values of the primary and secondary RLC entity logical channels are both non-zero, the amount of data sent on the corresponding RLC entity logical channels is calculated as follows: The amount of data transmitted by the RLC entity logical channel = the total amount of data to be transmitted * the transmission state coefficient of the RLC entity logical channel / the sum of the transmission state coefficients of the primary and auxiliary RLC entity logical channels; Step S4: The primary and secondary RLC entities process and send the data to be sent, and each reports the status of the logical channel to the PDCP entity; Step S5: Analyze the transmission status. If a preset situation exists, recover and transfer the data. In step S5: PDCP performs transmission status analysis. If the coefficient of sending one logical channel is less than a preset value and the coefficient of another logical channel is greater than a preset value, part or all of the to-be-sent data on the logical channel with the coefficient less than the preset value will be transferred to the logical channel with the coefficient greater than the preset value for transmission. The amount of data sent to RLC does not exceed the free space in the RLC buffer. Whether partial or full transfer is determined by the transmission state coefficient. A transmission state coefficient of 0 means that data can no longer be transmitted and all data is transferred. A non-zero transmission state coefficient means that data can still be transmitted, but the transmission efficiency is reduced and part of the data is transferred. The amount of data transferred = total cached data amount * (1-transmission state coefficient).

2. The efficient 5G dual-connectivity split bearer data transmission method according to claim 1, characterized in that: By monitoring and comparing the data buffer status and transmission status of the primary and secondary RLC entity logical channels, the data to be transmitted is reasonably distributed. The amount of data distributed to the logical channel cannot exceed the free space in the buffer area. If the buffer area is full, no data will be sent to the logical channel of the path where the logical channel is located; The data cache capacity status refers to the ratio of the amount of data to be transmitted to the total amount of data that can be cached in the cache area; The transmission status refers to the status of data transmission, and the air interface data transmission rate and the transmission packet error rate are used as indicators of the transmission status.

3. The efficient 5G dual-connection split bearer data transmission method according to claim 1, characterized in that: In step S1: Initialize the transmission state coefficient of the primary RLC entity and the secondary RLC entity logical channel to 1 and the buffer state to empty; The factors that determine the weighting of the transmission status coefficient of the logical channel include: The average transmission rate of the logical channel over a period of time, where the period of time consists of one or more transmission intervals. The higher the average transmission rate, the higher the transmission state coefficient. If the average transmission rate is 0, the transmission state coefficient is 0. For the AM RLC sending entity, the amount of data that can be sent in the sending window. If the sent data has not received confirmation from the receiving end, the amount of data that can be sent in the sending window will decrease until the sending window is congested. The more congested the sending window is, the lower the transmission state coefficient will be. If the sending window is completely congested, the transmission state coefficient will be 0. For the AM RLC sending entity, the packet error rate of data transmission reflects the channel quality. The packet error rate is calculated by counting the number of unacknowledged packets in the status report sent by the receiving end. The lower the packet error rate, the higher the transmission status coefficient.

4. The efficient 5G dual-connectivity split bearer data transmission method according to claim 1, characterized in that: In step S2: PDCP receives user data transmission requests from upper layers and places the data to be transmitted into a transmission queue after protocol processing.

5. The efficient 5G dual-connectivity split bearer data transmission method according to claim 1, characterized in that: In step S4: The primary and secondary RLC entities process and send the data to be sent according to the 3GPP protocol; The primary and secondary RLC entities each report the transmission status and buffer status of the logical channel to the PDCP entity.

6. An efficient 5G dual-connection split bearer data transmission system, characterized in that: include: Module M1: establishes dual-connection split bearer and initializes the state coefficients of the primary RLC entity and the secondary RLC entity; Module M2: receives a data transmission request, processes the data to be transmitted, and puts it into the sending queue; Module M3: performs data diversion and transmission; In the module M3: If the amount of data to be sent does not exceed the offload threshold, it is sent on the primary RLC entity. If the amount of data to be sent exceeds the offload threshold, PDCP compares the transmission status coefficients of the logical channels of the primary and secondary RLC entities and distributes the user data to be transmitted proportionally, so that the amount of data sent to RLC does not exceed the free space in the RLC buffer area. The offload threshold is configured by the base station to control whether the terminal can enable the offload function. If the data volume does not exceed the offload threshold, there is no need to enable the offload transmission function. Proportional allocation logic: If the transmission state coefficient value of any RLC entity logical channel in the primary and secondary RLC entities is 0, no data to be transmitted is sent to the RLC entity; If the transmission state coefficient values of the primary and secondary RLC entity logical channels are both non-zero, the amount of data sent on the corresponding RLC entity logical channels is calculated as follows: The amount of data transmitted by the RLC entity logical channel = the total amount of data to be transmitted * the transmission state coefficient of the RLC entity logical channel / the sum of the transmission state coefficients of the primary and auxiliary RLC entity logical channels; Module M4: The primary and secondary RLC entities process and send data to be sent, and each reports the status of the logical channel to the PDCP entity; Module M5: Analyze the transmission status and if there is a preset situation, recover and transfer the data; In the module M5: PDCP performs transmission status analysis. If the coefficient of sending one logical channel is less than a preset value and the coefficient of another logical channel is greater than a preset value, part or all of the to-be-sent data on the logical channel with the coefficient less than the preset value will be transferred to the logical channel with the coefficient greater than the preset value for transmission. The amount of data sent to RLC does not exceed the free space in the RLC buffer. Whether partial or full transfer is determined by the transmission state coefficient. A transmission state coefficient of 0 means that data can no longer be transmitted and all data is transferred. A non-zero transmission state coefficient means that data can still be transmitted, but the transmission efficiency is reduced and part of the data is transferred. The amount of data transferred = total cached data amount * (1-transmission state coefficient).

7. The efficient 5G dual-connectivity split bearer data transmission system according to claim 6, characterized in that: By monitoring and comparing the data buffer status and transmission status of the primary and secondary RLC entity logical channels, the data to be transmitted is reasonably distributed. The amount of data distributed to the logical channel cannot exceed the free space in the buffer area. If the buffer area is full, no data will be sent to the logical channel of the path where the logical channel is located; The data cache capacity status refers to the ratio of the amount of data to be transmitted to the total amount of data that can be cached in the cache area; The transmission status refers to the status of data transmission, and the air interface data transmission rate and the transmission packet error rate are used as indicators of the transmission status.

8. The efficient 5G dual-connection split bearer data transmission system according to claim 6, characterized in that: In the module M1: Initialize the transmission state coefficient of the primary RLC entity and the secondary RLC entity logical channel to 1 and the buffer state to empty; The factors that determine the weighting of the transmission status coefficient of the logical channel include: The average transmission rate of the logical channel over a period of time, where the period of time consists of one or more transmission intervals. The higher the average transmission rate, the higher the transmission state coefficient. If the average transmission rate is 0, the transmission state coefficient is 0. For the AM RLC sending entity, the amount of data that can be sent in the sending window. If the sent data has not received confirmation from the receiving end, the amount of data that can be sent in the sending window will decrease until the sending window is congested. The more congested the sending window is, the lower the transmission state coefficient will be. If the sending window is completely congested, the transmission state coefficient will be 0. For the AM RLC sending entity, the packet error rate of data transmission reflects the channel quality. The packet error rate is calculated by counting the number of unacknowledged packets in the status report sent by the receiving end. The lower the packet error rate, the higher the transmission status coefficient.

9. The efficient 5G dual-connectivity split bearer data transmission system according to claim 6, characterized in that: In the module M2: PDCP receives user data transmission requests from upper layers and places the data to be transmitted into a transmission queue after protocol processing.

10. The efficient 5G dual-connection split bearer data transmission system according to claim 6, characterized in that: In the module M4: The primary and secondary RLC entities process and send the data to be sent according to the 3GPP protocol; The primary and secondary RLC entities each report the transmission status and buffer status of the logical channel to the PDCP entity.

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