A HARQ scheduling method and device for NR system

Abstract

The present invention records a HARQ scheduling method and device for NR system, which obtains the first channel quality indication CQI1 reported by the terminal UE last time; schedules the new transmission data, the physical layer uses the RV0 redundant version, and saves each RV; receives the ACK information fed back by the UE; if the ACK information is negative feedback, reads the second channel quality indication CQI2 reported by the current terminal UE; calculates the difference between the two CQIs, and determines whether the difference exceeds the threshold K; if it exceeds, uses the new modulation and coding strategy MCS and resource allocation method, recalculates each RV, and uses the RV0 redundant version to schedule the new transmission data. In addition, a HARQ scheduling device for NR system is also provided, including a recording module and a scheduling module. When the channel quality changes dramatically, the new transmission is directly scheduled to avoid the delay caused by retransmission and improve the data transmission efficiency; the RV version for scheduling retransmission is selected according to the statistical average number of RV transmissions to ensure that the optimal RV is scheduled for transmission, effectively reducing the number of retransmissions.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technologies, and in particular to a HARQ scheduling method and device and an electronic device for a NR system. Background Art

[0002] This section is intended to provide a background or context to embodiments of the invention that are recited in the claims. No description herein is admitted to be prior art by inclusion in this section.

[0003] With the development of mobile Internet, more and more devices are connected to mobile networks, and new services and applications are emerging. The surge in mobile data traffic will bring severe challenges to the network. In order to meet the growing demand for mobile traffic, the fifth generation (5G) mobile communication network came into being. The data transmission rate of 5G network is faster than wired Internet, 100 times faster than the previous 4G LTE cellular network, and has lower network latency.

[0004] In wireless communication systems, wireless channels are a metaphor for the path between the transmitter and receiver in wireless communication, which is often referred to as wireless frequency bands (Channels). Digital data channels can provide high-speed data transmission services for mobile users. In the 5G NR communication system, incremental redundancy (IR) is used for data channel transmission. The incremental redundancy (IR) scheme is one of the HARQ merging schemes with soft merging, which can generally be divided into tracking merging and incremental redundancy. In the incremental redundancy (IR) scheme, each retransmission does not need to carry exactly the same content as the original transmission. Instead, multiple sets of coded bits will be generated, each representing the same set of information bits. Whenever a retransmission is required, a different set of coded bits is usually used than in the previous transmission. The receiver merges the retransmission packet with the previous transmission attempt of the same data packet. That is, incremental redundancy (IR) divides the transmitted data into multiple sets of coded bits. When retransmission is required, a different set of coded bits from the previous one is usually transmitted, called a different redundant version (RV). Each RV carries a different parity bit. The receiving end combines the retransmitted data with the previously transmitted data.

[0005] Since retransmissions may carry extra parity bits that were not included in the previous transmission, retransmissions usually result in a reduction in the coding rate. And as the number of retransmissions increases, the receiver will accumulate more parity bits, increasing the probability of decoding. In addition, each retransmission does not necessarily have to contain the same number of coded bits as the original transmission, and different modulation methods can usually be used in different retransmissions.

[0006] When performing HARQ transmission, increasing the number of retransmissions can increase the success rate of demodulation at the receiving end, but at the same time, multiple retransmissions will cause transmission delays, which is intolerable in many scenarios. In addition, since each redundant version of HARQ transmission contains different content, the probability of decoding at the receiving end is also different. Therefore, it is very important to select the HARQ scheduling strategy to reduce the delay caused by retransmission while ensuring correct decoding at the receiving end.

[0007] Therefore, it is necessary to provide a HARQ scheduling method and device for an NR system with intelligent adjustment of scheduling strategy and low delay to optimize system resource allocation.

[0008] Terminology explanation:

[0009] NR: New Radio, new air interface, fifth generation new radio.

[0010] HARQ: Hybrid Automatic Repeat Request, is a technology that combines forward error correction coding and automatic repeat request (ARQ). The keywords of HARQ are storage, request retransmission, and combined demodulation. In the case of decoding failure, the receiving end saves the received data and asks the sending end to retransmit the data. The receiving end combines the retransmitted data with the previously received data before decoding.

[0011] RV: Redundancy Version, redundancy version, used to implement incremental redundancy (IR) HARQ transmission, that is, the redundant bits generated by the encoder are divided into several groups. Each RV defines a transmission starting point. Different RVs are used for the first transmission and each HARQ retransmission to achieve gradual accumulation of redundant bits and complete the incremental redundancy HARQ operation.

[0012] ACK: Acknowledge character. In data communication, a transmission control character sent by the receiving end to the sending end indicates that the received data has been confirmed to be received correctly.

[0013] MCS: Modulation and Coding Scheme, modulation and coding strategy, implements the configuration of 802.11n radio rate. Each MCS index value corresponds to the physical transmission rate under a set of parameters. MCS is used to indicate the modulation and coding method of the data. Summary of the invention

[0014] In order to solve the above problems, the present invention provides a HARQ scheduling method and device for a NR system, which can optimize the redundancy version selection during the transmission process, reduce the number of HARQ retransmissions, and achieve the effect of improving data transmission efficiency and reducing delay.

[0015] To achieve the above object, the present invention provides a HARQ scheduling method for a NR system, comprising the following steps:

[0016] S1: Obtain the first channel quality indicator CQI1 reported by the terminal UE last time;

[0017] S2: Schedule new data transmission. The physical layer uses the RV0 redundancy version and saves each RV.

[0018] S3: receiving ACK information fed back by UE;

[0019] S4: If the ACK information is negative feedback, read the second channel quality indicator CQI2 reported by the current terminal UE;

[0020] S5: Calculate the difference between the two CQIs, and determine whether the difference exceeds a threshold value K;

[0021] S6: If it exceeds, use the new modulation and coding strategy MCS and resource allocation method, recalculate each RV, and use the RV0 redundancy version to schedule new transmission data.

[0022] Optionally, the following process is also included before step S1:

[0023] Step S0-1: After each HARQ transmission is completed, the average number of transmissions of each redundancy version RV is recorded.

[0024] Optionally, the following process is also included after step S3:

[0025] Step 3-1: If the ACK information is positive feedback, return to step S2.

[0026] Optionally, if the difference does not exceed the threshold K, step S7 is executed: a non-0RV redundant version with a smaller average number of transmission times is selected for retransmission scheduling.

[0027] Optionally, the threshold K value is 2.

[0028] Optionally, in step S7, if the average number of transmissions is the same, the retransmission of the redundancy version RV is scheduled in the order of versions 2, 3, and 1, and the physical layer uses the saved data.

[0029] In addition, the present invention also provides a HARQ scheduling device for an NR system, including:

[0030] A recording module, used to record the first channel quality indicator CQI1 reported by the terminal UE last time, and record the second channel quality indicator CQI2 reported by the current terminal UE, and record the average number of transmissions of each redundancy version RV after each HARQ transmission is completed;

[0031] The scheduling module is used to schedule new transmission data. The physical layer uses the RV0 redundancy version and saves each RV; receives the ACK information fed back by the UE. If the ACK information is negative feedback, reads the second channel quality indication CQI2 reported by the current terminal UE; calculates the difference between the two CQIs, and determines whether the difference exceeds the threshold K. If so, uses the new modulation and coding strategy MCS and resource allocation method, recalculates each RV, and uses the RV0 redundancy version to schedule new transmission data.

[0032] Optionally, if the scheduling module determines that the difference does not exceed a threshold value K, it selects a non-0RV redundant version with a smaller average number of transmission times for retransmission scheduling, where the threshold value K is 2.

[0033] Optionally, if the average number of transmissions is the same, the scheduling module schedules the retransmission of the redundant version RV in the order of versions 2, 3, and 1, and the physical layer uses the saved data.

[0034] In addition, the present invention also provides an electronic device, comprising:

[0035] Memory for storing computer programs;

[0036] The processor is used to execute the computer program stored in the memory, and when the computer program is executed, the above-mentioned HARQ scheduling method for the NR system is implemented.

[0037] The advantages and beneficial effects of the present invention are as follows: Compared with the situation where there is a delay problem in HARQ transmission scheduling in the existing NR system, the present invention provides a HARQ scheduling method and device for the NR system. When scheduling transmission, refer to the channel quality indication CQI reported by the receiving end, judge the retransmission scheme according to the CQI, and perform HARQ scheduling. The channel quality is taken into account when scheduling retransmission. When the channel quality changes drastically (CQI interpolation is greater than the threshold K), the new transmission is directly scheduled according to the channel status to avoid the delay caused by retransmission and improve data transmission efficiency. When selecting to schedule retransmission, the RV version for scheduling retransmission is selected based on the statistical average number of RV transmissions to ensure that the optimal RV is scheduled for transmission, effectively reducing the number of retransmissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only partial introductions to some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 A schematic diagram of a flow chart of a HARQ scheduling method for an NR system in an embodiment is shown; DETAILED DESCRIPTION

[0040] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings and examples. It should be understood that these embodiments are provided only to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0041] Those skilled in the art know that the embodiments of the present invention can be implemented as a method, system, apparatus, device or computer program product, etc. Therefore, the present disclosure can be specifically implemented in the following forms, namely: complete hardware, complete software (including firmware, resident software, microcode, etc.), or a combination of hardware and software.

[0042] In one embodiment, the present invention provides a HARQ scheduling method for a NR system, which is applied to a 5G communication system. Figure 1 As shown, when scheduling transmission, the present invention refers to the channel quality indicator CQI reported by the receiving end, determines the retransmission scheme according to the CQI, and intelligently adjusts the HARQ scheduling strategy. When the channel quality changes drastically, the new transmission is directly scheduled according to the channel status to avoid the delay caused by retransmission and improve the data transmission efficiency. And when scheduling the RV version of the retransmission, it is selected according to the statistical average number of RV transmissions to ensure that the optimal RV is scheduled for transmission, effectively reducing the number of retransmissions.

[0043] In this embodiment, a HARQ scheduling method for an NR system is provided, including the following steps:

[0044] S1: Obtain the first channel quality indicator CQI1 reported by the terminal UE (User Equipment) last time;

[0045] S2: Schedule new data transmission. The physical layer uses the RV0 redundancy version and saves each RV.

[0046] S3: receiving ACK information fed back by UE;

[0047] S4: If the ACK information is negative feedback (NACK), read the second channel quality indicator CQI2 reported by the current terminal UE;

[0048] S5: Calculate the difference between the two CQIs (|CQI1-CQI2|), and determine whether the difference exceeds a threshold K;

[0049] S6: If it exceeds, use the new modulation and coding strategy MCS and resource allocation method, recalculate each RV, and use the RV0 redundancy version to schedule new transmission data.

[0050] Among them, CQI (Channel Quality Indicator) represents the quality of the current channel, which corresponds to the signal-to-noise ratio of the channel and has a value range of 0 to 31. When the CQI value is 0, the channel quality is the worst; when the CQI value is 31, the channel quality is the best. Common values ​​are 12 to 24. The CQI of a given channel depends on the transmission (modulation) scheme used by the communication system.

[0051] The HARQ operation corresponds to four different redundancy versions, RV = 0, 1, 2, and 3. The starting position of the bit stream extracted from the circulator will be different depending on the HARQ redundancy version RV value.

[0052] The ACK information NACK (Negative Acknowledgement) fed back by the UE is a negative feedback. The receiver notifies the sender only when it has not received the data. The receiver periodically notifies the sender of all the unreceived packet sequence numbers through feedback messages for retransmission. This can reduce the frequency of feedback packets and bandwidth usage, and can also notify the sender in a timely manner to retransmit lost packets.

[0053] Preferably, the following process is also included before step S1:

[0054] Step S0-1: After each HARQ transmission is completed, the average number of transmissions of each redundancy version RV is recorded.

[0055] Preferably, the following process is also included after step S3:

[0056] Step 3-1: If the ACK information is positive feedback, return to step S2, schedule new transmission data, the physical layer uses RV0, and saves each RV.

[0057] Preferably, the threshold K value is 2. When the difference |CQI1-CQI2| exceeds the threshold 2, it can be considered that the channel quality has changed dramatically. At this time, the new transmission is directly scheduled, that is, the new modulation and coding strategy MCS and resource allocation method are used, each RV is recalculated, and the RV0 redundancy version is used to schedule the new transmission data. This avoids the delay caused by retransmission and improves data transmission efficiency.

[0058] Preferably, if the difference |CQI1-CQI2| does not exceed the threshold value K, step S7 is performed: a non-0RV redundant version with a smaller average number of transmissions is selected for retransmission scheduling. When |CQI1-CQI2|≤2, it can be considered that the channel quality is relatively stable and retransmission can be selected. At this time, when scheduling the RV version for retransmission, the selection is made based on the statistical average number of RV transmissions to ensure that the optimal RV is scheduled for transmission, effectively reducing the number of retransmissions.

[0059] Preferably, in step S7, if the average number of transmissions is the same, the retransmission of the redundancy version RV is scheduled in the order of versions 2, 3, and 1, and the physical layer uses the stored data.

[0060] like Figure 1 As shown, this embodiment provides a HARQ scheduling method for an NR system, and the specific operation process is as follows:

[0061] Step S0-1: After each HARQ transmission is completed, record the average number of transmissions of each redundancy version RV;

[0062] S1: Obtain the first channel quality indicator CQI1 reported by the terminal UE last time;

[0063] S2: Schedule new data transmission. The physical layer uses the RV0 redundancy version and saves each RV.

[0064] S3: receiving ACK information fed back by UE;

[0065] Step 3-1: If the ACK information is positive feedback, return to step S2, schedule new transmission data, the physical layer uses RV0, and saves each RV.

[0066] S4: If the ACK information is negative feedback NACK, read the second channel quality indicator CQI2 reported by the current terminal UE;

[0067] S5: Calculate the difference between the two CQIs (|CQI1-CQI2|), and determine whether the difference exceeds a threshold K;

[0068] S6: If the difference |CQI1-CQI2| exceeds the threshold K, the new modulation and coding strategy MCS and resource allocation method are used to recalculate each RV, and the RV0 redundancy version is used to schedule the new transmission data, that is, jump to step S2;

[0069] S7: If the difference |CQI1-CQI2| does not exceed the threshold K, the non-0RV redundant version with a smaller average transmission number is preferentially selected for retransmission scheduling; when the average transmission number is the same, the retransmission redundant version RV is scheduled in the order of version 2, 3, and 1, that is, the redundant version RV2, RV3, and RV1 are scheduled in the order, and the physical layer uses the saved data.

[0070] In addition, in one embodiment, the present invention further provides a HARQ scheduling device for an NR system, the device including but not limited to a recording module and a scheduling module, wherein:

[0071] A recording module, used to record the first channel quality indicator CQI1 reported by the terminal UE last time, and record the second channel quality indicator CQI2 reported by the current terminal UE, and record the average number of transmissions of each redundancy version RV after each HARQ transmission is completed;

[0072] The scheduling module is used to schedule new transmission data. The physical layer uses the RV0 redundancy version and saves each RV; receives the ACK information fed back by the UE. If the ACK information is negative feedback, reads the second channel quality indication CQI2 reported by the current terminal UE; calculates the difference between the two CQIs, and determines whether the difference exceeds the threshold K. If so, uses the new modulation and coding strategy MCS and resource allocation method, recalculates each RV, and uses the RV0 redundancy version to schedule new transmission data.

[0073] Preferably, if the scheduling module determines that the difference does not exceed a threshold value K, the scheduling module selects a non-0RV redundant version with a smaller average number of transmissions for retransmission scheduling, wherein the threshold value K is 2. If the average number of transmissions is the same, the scheduling module schedules the retransmission redundant version RV in the order of version 2, 3, and 1, and the physical layer uses the saved data.

[0074] In addition, in one embodiment, the present invention further provides an electronic device, including:

[0075] Memory for storing computer programs;

[0076] The processor is used to execute the computer program stored in the memory, and when the computer program is executed, the above-mentioned HARQ scheduling method for the NR system is implemented.

[0077] The electronic device in this embodiment may be an integrated circuit board, a PC (Personal Computer), a portable computer or other electronic devices with a processor.

[0078] The memory may include a computer system readable medium in the form of a volatile memory, such as a random access memory (RAM) and / or a cache memory. The processor executes various functional applications and data processing by running a computer program stored in the memory. Specifically, the processor may execute a computer program stored in the memory, and when the computer program is executed, at least the following instructions are executed:

[0079] S1: Obtain the first channel quality indicator CQI1 reported by the terminal UE last time;

[0080] S2: Schedule new data transmission. The physical layer uses the RV0 redundancy version and saves each RV.

[0081] S3: receiving ACK information fed back by UE;

[0082] S4: If the ACK information is negative feedback, read the second channel quality indicator CQI2 reported by the current terminal UE;

[0083] S5: Calculate the difference between the two CQIs, and determine whether the difference exceeds a threshold value K;

[0084] S6: If it exceeds, use the new modulation and coding strategy MCS and resource allocation method, recalculate each RV, and use the RV0 redundancy version to schedule new transmission data.

[0085] In addition, although the operations of the method of the present invention are described in a specific order in the drawings, this does not require or imply that the operations must be performed in this specific order, or that all the operations shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps.

[0086] Although the spirit and principle of the present invention have been described with reference to the above specific embodiments, it should be understood that the present invention is not limited to the disclosed specific embodiments, and the division of various aspects does not mean that the features in these aspects cannot be combined to benefit, and such division is only for the convenience of expression. The present invention is intended to cover various modifications and equivalent arrangements included in the spirit and scope of the attached claims.

Claims

1. A HARQ scheduling method for a NR system, characterized in that: The following steps are involved: S1: Obtain the first channel quality indicator CQI1 reported by the terminal UE last time; S2: Schedule new data transmission. The physical layer uses the RV0 redundancy version and saves each RV redundancy version. S3: receiving ACK information fed back by UE; S4: If the ACK information is negative feedback, read the second channel quality indicator CQI2 reported by the current terminal UE; S5: Calculate the difference between the two CQIs, and determine whether the difference exceeds a threshold value K; S6: If it exceeds, use the new modulation and coding strategy MCS and resource allocation method to recalculate each RV, and use the RV0 redundancy version to schedule the new transmission data; if the difference does not exceed the threshold K, execute step S7: select the non-0RV redundancy version with a smaller average transmission number for retransmission scheduling; In step S7, if the average number of transmissions is the same, the redundancy version RV is retransmitted in the order of version 2, 3, and 1, and the physical layer uses the saved data; The receiver sends negative feedback only when it does not receive data, and periodically notifies the sender of all unreceived packet numbers through feedback messages.

2. A HARQ scheduling method for an NR system according to claim 1, characterized in that: The following process is also included before step S1: Step S0-1: After each HARQ transmission is completed, the average number of transmissions of each redundancy version RV is recorded.

3. A HARQ scheduling method for NR system according to claim 1, characterized in that: After step S3, the following process is also included: Step 3-1: If the ACK information is positive feedback, return to step S2.

4. The HARQ scheduling method for NR system according to claim 1, characterized in that: The threshold K value is 2.

5. A HARQ scheduling device using the HARQ scheduling method for NR system according to claim 1, characterized in that: include: A recording module, used to record the first channel quality indicator CQI1 reported by the terminal UE last time, and record the second channel quality indicator CQI2 reported by the current terminal UE, and record the average number of transmissions of each redundancy version RV after each HARQ transmission is completed; The scheduling module is used to schedule new transmission data. The physical layer uses the RV0 redundancy version and saves each RV; receives the ACK information fed back by the UE. If the ACK information is negative feedback, reads the second channel quality indication CQI2 reported by the current terminal UE; calculates the difference between the two CQIs, and determines whether the difference exceeds the threshold K. If so, uses the new modulation and coding strategy MCS and resource allocation method, recalculates each RV, and uses the RV0 redundancy version to schedule new transmission data.

6. A HARQ scheduling device for an NR system according to claim 5, characterized in that: If the scheduling module determines that the difference does not exceed the threshold K, it selects a non-0RV redundant version with a smaller average number of transmission times for retransmission scheduling, where the threshold K value is 2.

7. The device for 5G NR system scheduling optimization according to claim 6, characterized in that: If the average number of transmissions is the same, the scheduling module schedules the retransmission of the redundant version RV in the order of versions 2, 3, and 1, and the physical layer uses the stored data.

8. An electronic device comprising: Memory for storing computer programs; A processor, configured to execute a computer program stored in a memory, and when the computer program is executed, implements the HARQ scheduling method for an NR system according to any one of claims 1 to 4.

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