A method for retransmission data control based on wireless channel quality

Abstract

The present invention relates to the field of wireless communication technologies, and particularly relates to a method for controlling retransmitted data based on wireless channel quality. Parameters such as a retransmission control rate, a retransmission times control threshold, a retransmission control increase step, a retransmission control decrease step, a retransmission times decrease threshold, and a retransmission times increase threshold are set. Furthermore, by determining whether the MCS in the timer is in a steady state and jointly adjusting the maximum retransmission times with the set parameters, the maximum retransmission times can be controlled according to the quality of the channel, achieving an adaptive adjustment of the maximum retransmission times. Therefore, by adaptively adjusting the maximum retransmission times, the present invention can reduce the waste of air interface resources while ensuring the effectiveness of data transmission.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technologies, and particularly relates to a method for controlling retransmitted data based on wireless channel quality. Background Art

[0002] In 5G communication, currently two frequency bands are mainly used, namely FR1 (sub 6Ghz) and FR2 (millimeter wave). In terms of data loss and errors, both are mainly processed by the harq (hybrid automatic repeat request) mechanism of the MAC (Medium Access Control) layer. That is, through harq with soft combining, the received error packets are saved in a harq buffer and merged with the retransmitted packets received subsequently to obtain a more reliable packet, and then the packet is decoded. If it still fails, retransmission is repeated and soft combining is performed again.

[0003] In the scheduling user DCI (Downlink Control Information), NDI (New Data Indicator) will be carried to indicate whether it is a new transmission (NDI flips) or a retransmission (NDI does not flip) under the same harq process ID; different RVs (redundant versions) are used for UL retransmission, and the RV is determined by DCI0.

[0004] Currently, for both FR1 and FR2, general manufacturers can set the maximum downlink and uplink retransmission times by themselves. Regardless of the quality of the channel, if the set maximum retransmission times all fail, that is, the retransmission fails. When the channel condition is poor, for example, the MCS (Modulation and coding scheme) has dropped to 0, most of the last few retransmission services still fail. Especially when a large traffic service is being carried out at this time, the RB occupancy will also be relatively large, and retransmission has a higher scheduling priority. The last few retransmissions are equivalent to occupying a large amount of air interface resources and are still ineffective scheduling, resulting in a large waste of air interface resources; when the MCS is stable at other levels (MCS > 0), it may occasionally happen that retransmission occurs 4 times, that is, the data transmission still fails, and the effectiveness of the data transmission on the air interface cannot be guaranteed at this time. Based on this, the setting of the maximum retransmission times does not consider the quality of the channel, resulting in a waste of air interface resources and unable to guarantee the effectiveness of data transmission. Therefore, there is an urgent need for a technology to control the maximum retransmission times according to the quality of the channel, so as to reduce the waste of air interface resources and ensure the effectiveness of data transmission. Summary of the Invention

[0005] To solve the problem that the setting of the maximum number of retransmissions does not consider the quality of the channel, resulting in a waste of radio interface resources and an inability to ensure the effectiveness of data transmission, the purpose of the present invention is to provide a method for controlling retransmitted data based on the quality of the wireless channel. The specific technical solution is as follows:

[0006] Set a retransmission control rate, a retransmission number control threshold, a retransmission control increase step size, a retransmission control decrease step size, a retransmission number decrease threshold, and a retransmission number increase threshold;

[0007] Determine whether the MCS in the timer is in a steady state;

[0008] When the MCS is in a steady state, start measuring the maximum number of retransmissions, and record the current retransmission control rate and MCS;

[0009] If the current retransmission control rate is greater than the retransmission number control threshold and the MCS is greater than 0, then add the retransmission control increase step size to the value of the retransmission number adjustment step size; if the MCS is equal to 0, then subtract the retransmission control decrease step size from the value of the retransmission number adjustment step size;

[0010] If the current retransmission control rate is less than or equal to the retransmission number control threshold, then subtract the retransmission control decrease step size from the value of the retransmission number adjustment step size; and so on. When the value of the retransmission number adjustment step size reaches the retransmission number decrease threshold, reduce the maximum number of retransmissions by a set number; when the value of the retransmission number adjustment step size reaches the retransmission number increase threshold, increase the maximum number of retransmissions by a set number;

[0011] When the MCS is not in a steady state, then clear the timer to 0, clear the measurement of the retransmission number to 0, and clear the retransmission number adjustment step size to 0.

[0012] Preferably, the retransmission control rate is the proportion of the number of times when the retransmission number in a certain number of packets is the maximum number of retransmissions.

[0013] Preferably, the retransmission number control threshold, the retransmission control increase step size, the retransmission control decrease step size, the retransmission number decrease threshold, and the retransmission number increase threshold can all be configured by the manufacturer itself.

[0014] The embodiments of the present invention have at least the following beneficial effects:

[0015] The present invention provides an effective guarantee for data transmission in FR1 and FR2 multi-user scenarios or scenarios with poor signal quality by setting a parameter retransmission control rate, a retransmission count control threshold, a retransmission control increase step, a retransmission control decrease step, a retransmission count decrease threshold, and a retransmission count increase threshold. By jointly adjusting the maximum retransmission count using the set parameters and channel quality, the maximum retransmission count can be adaptively adjusted according to the channel quality. This not only ensures the effectiveness of data transmission but also saves the use of air interface resources, enabling the full utilization of scheduling resources. Specifically, when the channel quality is extremely poor (MCS = 0), it saves the occupancy of air interface resources and enables the full utilization of scheduling resources; when the channel quality is good (MCS ≥ 1), it ensures the effectiveness of data transmission without wasting air interface resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the description of the embodiments or the prior art. Obviously, the following-described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0017] Figure 1 It is a flowchart of an embodiment of a method for retransmission data control based on wireless channel quality according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] To further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation manners, structures, features, and effects of the solution proposed according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0020] Please refer to Figure 1 , which shows a flowchart of a method for retransmission data control based on wireless channel quality provided by an embodiment of the present invention. The method includes the following steps:

[0021] Step 1, set a retransmission control rate, a retransmission count control threshold, a retransmission control increase step, a retransmission control decrease step, a retransmission count decrease threshold, and a retransmission count increase threshold.

[0022] The retransmission control ratio (RCR) is the ratio of the number of times the retransmission count reaches the maximum retransmission count within a certain number of packets. For example, if the current maximum retransmission count is configured as n times, and the ratio of the number of times the retransmission count reaches n times within 100 packets is m%, then the retransmission control ratio is m%; the retransmission control ratio is a parameter at the UE (user equipment) level.

[0023] The retransmission count control threshold (RCH) is set as the threshold value for adjusting the retransmission count. Similar to the Bler threshold, the retransmission count control threshold can be configured by the manufacturer itself. After reaching the retransmission count control threshold, the retransmission count is adjusted by the retransmission adjustment step size; RCH is a parameter at the base station level.

[0024] Preferably, the retransmission count control threshold, the retransmission control increase step size, the retransmission control decrease step size, the retransmission count decrease threshold, and the retransmission count increase threshold can all be configured by the manufacturer itself.

[0025] In this embodiment, the base station configures 4 cells. The maximum retransmission count for each cell in both the uplink and downlink is set to 4 times, supporting the 256Qam table. The uplink and downlink Bler thresholds are set to 10%, the retransmission count control threshold is set to 5%, the retransmission control increase step size is 1, the retransmission control decrease step size is 1, the retransmission count decrease threshold is -5, and the retransmission count increase threshold is 5. Each cell has 2 UEs (user equipment) respectively. The two UEs are connected and are in the midpoint and extremely poor points respectively. The identifiers of the two UEs in cell 1 are 61 and 125 respectively. As other implementation methods, the implementer can set the values of the retransmission count control threshold, the retransmission control increase step size, the retransmission control decrease step size, the retransmission count decrease threshold, and the retransmission count increase threshold according to the actual situation.

[0026] In the above embodiment, by setting parameters such as the retransmission control ratio, the retransmission count control threshold, the retransmission control increase step size, the retransmission control decrease step size, the retransmission count decrease threshold, and the retransmission count increase threshold, the purpose of adaptively adjusting the maximum retransmission count is achieved. It avoids the problems that in 5G FR1 and FR2, data error correction processing is all implemented by the MAC layer through the harq mechanism, and the retransmission does not adjust the MCS. The setting of the maximum retransmission count during retransmission is generally set by the manufacturer itself, and the inability to perform adaptive adjustment will cause a large amount of radio resource waste and the problem that the data transmission effectiveness of the radio interface cannot be guaranteed.

[0027] Step 2: Determine whether the MCS in the timer is in a steady state. When the MCS is in a steady state, start measuring the maximum retransmission times, and record the current retransmission control rate and MCS. If the current retransmission control rate is greater than the retransmission times control threshold and the MCS is greater than 0, then add the retransmission control boost step size to the value of the retransmission times adjustment step size. If the MCS is equal to 0, then subtract the retransmission control reduction step size from the value of the retransmission times adjustment step size. If the current retransmission control rate is less than or equal to the retransmission times control threshold, then subtract the retransmission control reduction step size from the value of the retransmission times adjustment step size. And so on. When the value of the retransmission times adjustment step size reaches the retransmission times reduction threshold, reduce the maximum retransmission times by a set number of times. When the value of the retransmission times adjustment step size reaches the retransmission times boost threshold, increase the maximum retransmission times by a set number of times. When the MCS is not in a steady state, clear the timer to 0, clear the retransmission times measurement to 0, and clear the retransmission times adjustment step size to 0.

[0028] MCS refers to the base station telling the terminal what modulation method and coding rate the PDSCH channel transmitted by the base station uses, or what modulation method and coding rate the terminal should use when transmitting the PUSCH channel.

[0029] Specifically, the method for determining whether the MCS in the timer is in a steady state is as follows: After the timer times out, determine whether the value of the MCS is stably at a fixed value without change. If, after the timer times out, the value of the MCS is stably at a fixed value without change, then it is determined that the MCS in the timer is in a steady state. For example, after the timer times out, the value of the MCS is stably at 0 without change, which indicates that the MCS is in a steady state and the MCS is stably 0. If the value of the MCS changes after the timer times out, then it is determined that the MCS in the timer is not in a steady state.

[0030] It should be noted that the initial value of the retransmission times adjustment step size is 0, and the change of the retransmission times adjustment step size is divided into 2 cases, namely, the first case of change: add the retransmission control boost step size to the value of the retransmission times adjustment step size; the second case of change: subtract the retransmission control reduction step size from the value of the retransmission times adjustment step size.

[0031] When the MCS is in a steady state, start measuring the maximum retransmission times, and record the current retransmission control rate and MCS. If the current retransmission control rate is greater than the retransmission times control threshold and the MCS is greater than 0, then add the retransmission control boost step size to the value of the retransmission times adjustment step size, corresponding to the first case of change of the retransmission times adjustment step size.

[0032] When the MCS is in a steady state, start measuring the maximum number of retransmissions, and record the current retransmission control rate and MCS; if the current retransmission control rate is greater than the retransmission number control threshold and the MCS is equal to 0, then the value of the retransmission number adjustment step size minus the retransmission control reduction step size corresponds to the second change case of the retransmission number adjustment step size.

[0033] When the MCS is in a steady state, start measuring the maximum number of retransmissions, and record the current retransmission control rate and MCS; if the current retransmission control rate is less than or equal to the retransmission number control threshold, then the value of the retransmission number adjustment step size minus the retransmission control reduction step size also corresponds to the second change case of the retransmission number adjustment step size.

[0034] Furthermore, when the value of the retransmission number adjustment step size reaches the retransmission number reduction threshold, reduce the maximum number of retransmissions by a set number; when the value of the retransmission number adjustment step size reaches the retransmission number increase threshold, increase the maximum number of retransmissions by a set number.

[0035] In this embodiment, UE125 performs ordinary data services at the extremely poor point, obtains the MCS at this point, the MCS is stable at 0 within the timer, and the Bler threshold is about 30%.

[0036] Measure and count the number of retransmissions when the MCS of UE125 is stable at 0. If the proportion of 4 retransmissions reaches 5%, that is, the retransmission control rate reaches the retransmission number control threshold, then the value of the retransmission number adjustment step size is -1. Since the initial value of the retransmission number adjustment step size is 0, the value of the retransmission number adjustment step size is -1 at this time. When the value of the retransmission number adjustment step size is -5, the number of retransmissions is reduced by 1 time, and the number of retransmissions at this time is 3 times. Then the maximum number of retransmissions maintained by this UE is changed to 5, corresponding to reducing the set number by 1 for the maximum number of retransmissions. In this embodiment, the value of the set number is 1. As other implementation manners, the implementer can also adjust the value of the set number according to the actual situation.

[0037] It should be noted that if the number of retransmissions of UE61 is reduced to 3 times, the maximum number of retransmissions maintained by this UE is changed to the statistics when the retransmission reaches 3 times.

[0038] In this embodiment, UE61 performs ordinary data services at the midpoint, obtains the MCS at this point, the MCS is in a steady state within the timer, for example, the MCS is stable at 12, and the Bler threshold fluctuates between 5% and 10%.

[0039] Measure and count the number of retransmissions of UE61 when the MCS is stable at 12. If the proportion of the number of retransmissions reaching 4 times reaches 5%, that is, the retransmission control rate reaches the retransmission number control threshold, then the value of the retransmission number adjustment step is increased by 1. If the proportion of the number of retransmissions reaching 4 times does not reach 5%, then the value of the retransmission number adjustment step is decreased by 1, and so on. When the value of the retransmission number adjustment step reaches 5, the number of retransmissions of this UE is increased by 1 to be 5 retransmissions, that is, the value of the maximum number of retransmissions is 5; when the value of the retransmission number adjustment step reaches -5, the number of retransmissions is decreased by 1 to be 3 retransmissions, that is, the value of the maximum number of retransmissions is 3. Among them, the value of the maximum number of retransmissions has a maximum value and a minimum value. In this embodiment, the maximum value is set to 6 and the minimum value is set to 3. In the specific operation process, the implementer can adjust the values of the maximum and minimum values according to the actual situation.

[0040] In this embodiment, if the number of retransmissions of UE61 reaches 5 times, the maximum number of retransmissions maintained for this UE is changed to the statistics of reaching 5 retransmissions.

[0041] It is judged that the priority of the 5th retransmission of UE61 user is reduced, that is, the scheduling priority is retransmission > new transmission > 5th and 6th retransmissions, so as to ensure the traffic stability of other users during multi-user scheduling.

[0042] It should be noted that a retransmitted data control method based on wireless channel quality proposed by the present invention adjusts the maximum number of retransmissions by setting parameters, namely retransmission control rate, retransmission number control threshold, retransmission control increase step, retransmission control decrease step, retransmission number decrease threshold, and retransmission number increase threshold; and jointly adjusts the maximum number of retransmissions by using the set parameters and channel quality, so that the maximum number of retransmissions can be adaptively adjusted according to the channel quality, which can further ensure the data transmission reliability of the UE when MCS > 0, and avoid the waste of radio interface resources caused by multiple ineffective retransmissions at extremely poor points when MCS = 0.

[0043] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for retransmission data control based on wireless channel quality, characterized in that, The method includes the following steps: Set a retransmission control rate, a retransmission times control threshold, a retransmission control increase step size, a retransmission control decrease step size, a retransmission times decrease threshold, and a retransmission times increase threshold. The retransmission control rate is the proportion of the number of times when the retransmission times within a certain number of packets reach the maximum retransmission times; Judge whether the MCS in the timer is in a steady state; When the MCS is in a steady state, start measuring the maximum retransmission times, and record the current retransmission control rate and MCS; If the current retransmission control rate is greater than the retransmission times control threshold and the MCS is greater than 0, then add the retransmission control increase step size to the value of the retransmission times adjustment step size; if the MCS is equal to 0, then subtract the retransmission control decrease step size from the value of the retransmission times adjustment step size; If the current retransmission control rate is less than or equal to the retransmission times control threshold, then subtract the retransmission control decrease step size from the value of the retransmission times adjustment step size; when the value of the retransmission times adjustment step size reaches the retransmission times decrease threshold, reduce the maximum retransmission times by a set number of times; when the value of the retransmission times adjustment step size reaches the retransmission times increase threshold, increase the maximum retransmission times by a set number of times; When the MCS is not in a steady state, clear the timer to 0, clear the retransmission times measurement to 0, and clear the retransmission times adjustment step size to 0.

2. The retransmission data control method based on wireless channel quality according to claim 1, characterized in that The retransmission times control threshold, the retransmission control increase step size, the retransmission control decrease step size, the retransmission times decrease threshold, and the retransmission times increase threshold can all be configured by the manufacturer himself.

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