CN101207461B - Method and apparatus for self-adapting regulation of threshold value - Google Patents

Abstract

The embodiment of the present invention discloses a method for self-adaptive adjustment of a threshold value. The method includes: obtaining information on the receiving situation of data packets; adjusting the threshold value according to the adjustment mode corresponding to the information on receiving the data packets, The later threshold value is used as the current threshold value. The invention also discloses a threshold value adaptive adjustment device. The application of the present invention can realize the adaptive adjustment of the threshold value, so that the control operation based on the threshold value can adapt to the requirements of the rapidly changing wireless environment and improve the communication quality.

Description

A method and device for adaptive threshold value adjustment

technical field

The invention relates to control technology, in particular to a threshold value self-adaptive adjustment method and device. the

Background technique

The IEEE 802.16e protocol makes it possible to use a terminal to enjoy wireless broadband access services at any time and anywhere. The Worldwide Interoperability for Microwave Access Forum (WIMAX, Worldwide Interoperability for Microwave Access Forum) system based on the IEEE 802.16e protocol appears. become a hot spot of concern. Key technologies such as Hybrid Automatic Repeat Request (HARQ, Hybrid Automatic Repeat Request) and Adaptive Modulation and Coding (AMC, Adaptive Modulation and Coding), etc., enable the WIMAX system to further improve the main performance such as speed, throughput and capacity. the

In the WIMAX system, control operations such as AMC control and power control need to involve the use of threshold values. Taking AMC control as an example, in the downlink direction, that is, when the base station (BS, Base Station) sends data packets to the mobile station (MS, Mobile Station), downlink AMC control is required. In the uplink direction, that is, the MS sends data packets to the BS , uplink AMC control is required. The basic principle of AMC is to control the modulation and coding mode of data transmission. At present, the threshold value used in AMC control is a fixed threshold value, and the application of a fixed threshold value cannot meet the needs of rapidly changing wireless channels. the

Taking downlink AMC control as an example, the IEEE 802.16e protocol provides the following two ideas for downlink AMC control:

1) The AMC control implemented by the MS, the MS selects the downlink modulation and coding scheme (MCS, Modulation and Coding Scheme) according to the AMC threshold value, and measures the value through the effective carrier to interference and noise ratio (Effective CINR, Effective Carrier to interference and noise ratio) Inform the BS of the MCS method selected, and the BS uses the modulation and coding method specified in the MCS method selected by the MS for data transmission;

2) The AMC control implemented by the BS, the MS reports the physical CINR (Physical CINR) measurement value to the BS, and the BS selects the MCS mode according to the reported measurement value and the AMC threshold value, and then follows the modulation specified in the MCS mode selected by itself Encoding for data transmission. the

In the above-mentioned existing protocol, only the idea of how to use the threshold value to carry out related control operations is provided. In this idea, the fixed AMC threshold value is used, and it does not involve what standard the threshold value adaptive adjustment is based on, and how to Realize the adaptive adjustment of the threshold value. the

Taking the AMC control as an example above, it shows that in the existing scheme, the implementation of the fixed threshold value is adopted in the relevant control, which will cause the control operation based on the fixed threshold value to be unable to adapt to the requirements of the rapidly changing wireless environment. Reduced communication quality. the

An embodiment of the present invention provides a method for adaptive threshold value adjustment, which can realize adaptive threshold value adjustment, so that the control operation based on the threshold value can adapt to the requirements of the wireless environment and improve communication quality. the

An embodiment of the present invention provides a threshold value adaptive adjustment device, which can realize the threshold value adaptive adjustment, so that the control operation based on the threshold value can adapt to the requirements of the wireless environment, and improve the communication quality. the

The technical scheme of the embodiment of the present invention is realized like this:

A method for adaptive threshold value adjustment, preset adjustment step size Step_size and error packet number target value PER_Target, and set the current error packet number as Bad_Packet_Num, the current correct data packet number as Good_Packet_Num, then the lifting step size is Step_up=Bad_Packet_Num ×(Step_size-PER_Target×Step_size), reduce the step size to Step_down=Good_Packet_Num×PER_Target×Step_size; the method includes:

Obtaining information on the reception of data packets, including: counting the number of negative acknowledgment NACK information of the data packets, taking the number of data packets whose number of times the NACK information reaches the preset maximum number of retransmissions as the number of error packets, and counting the number of times of the NACK information that has reached the preset maximum number of retransmissions. The number of data packets reaching the preset maximum number of retransmissions is taken as the number of correct data packets;

Adjust the threshold value, including: if there is no data packet transmission, increase the threshold value by 0; or if there is data packet transmission, and there is currently an error packet, increase the threshold value by the above-mentioned lifting step; or if there is data packet transmission, And there is currently no error packet, and the threshold value is reduced by the step size;

Use the adjusted threshold as the current threshold. the

A device for adaptive threshold value adjustment, preset adjustment step size Step_size and error packet number target value PER_Target, and set the current error packet number as Bad_Packet_Num, and the current correct data packet number as Good_Packet_Num, then the lifting step size is Step_up=Bad_Packet_Num ×(Step_size-PER_Target×Step_size), reducing the step size is Step_down=Good_Packet_Num×PER_Target×Step_size; the device includes:

The information acquisition module includes: a second execution unit for counting the number of negative acknowledgment NACK information of the data packet; a second calculation unit for counting the number of NACK information counted by the second execution unit to a preset maximum number of retransmissions The number of data packets is used as the current number of error packets, and the number of data packets whose number of NACK information does not reach the preset maximum number of retransmissions is used as the current number of correct data packets;

The information acquisition module includes: a second execution unit for counting the number of negative acknowledgment NACK information of the data packet; a second calculation unit for counting the number of NACK information counted by the second execution unit to a preset maximum number of retransmissions The number of data packets is used as the current number of error packets, and the number of data packets whose number of NACK information does not reach the preset maximum number of retransmissions is used as the current number of correct data packets;

The adjustment module includes: a third determination unit, configured to determine whether there is currently a data packet transmission, and whether there is an error packet currently, to obtain a determination result; a third adjustment execution unit, configured to determine if the determination result of the third determination unit If there is currently no data packet transmission, add 0 to the threshold value; or if the determination result of the third determination unit is that there is currently data packet transmission and there is an error packet, increase the threshold value by the lifting step; or if the The determination result of the third determining unit is that there is currently data packet transmission and there is no packet error, and the threshold value is reduced by the reduction step; the adjusted threshold value is used as the current threshold value. the

It can be seen that the method and device for adaptive adjustment of the threshold value provided by the embodiments of the present invention adjust the threshold value according to the adjustment mode corresponding to the information of the data packet reception situation after obtaining the information of the data packet reception situation, and the The adjusted threshold value is used as the current threshold value, so that the adaptive adjustment of the threshold value is realized based on the information of the received data packet, so that the control operation based on the adaptively adjusted threshold value can adapt to the fast Changes in the wireless environment require improved communication quality. the

Description of drawings

Fig. 1 is the method flowchart of threshold value self-adaptive adjustment of the embodiment of the present invention;

Fig. 2 is the flow chart of threshold value adaptive adjustment based on ACK and NACK information in the embodiment of the present invention;

Fig. 3 is the flow chart of threshold value self-adaptive adjustment based on the average retransmission times of the embodiment of the present invention;

Fig. 4 is the schematic diagram that the embodiment of the present invention carries out adaptive adjustment of the threshold value based on the current number of error packets and the current number of correct data packets;

Fig. 5 is the flow chart that the embodiment of the present invention carries out threshold adaptive adjustment based on current error packet number and current correct data packet number;

Fig. 6 is the flow chart of the first specific example of the method for threshold value self-adaptive adjustment of the embodiment of the present invention;

Fig. 7 is the flow chart of the second specific example of the method for threshold value self-adaptive adjustment of the embodiment of the present invention;

FIG. 8 is a schematic structural diagram of a device for adaptive adjustment of a threshold value according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of an application of an apparatus for adaptively adjusting a threshold value in an ARQ/HARQ system according to an embodiment of the present invention. the

Detailed ways

In order to make the purpose and advantages of the embodiments of the present invention more clear, the embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings. the

Fig. 1 is the flow chart of the method for threshold value self-adaptive adjustment of the embodiment of the present invention, and this process comprises:

Step 101: Acquiring information about data packet reception. the

Step 102: Adjust the threshold value according to the adjustment method corresponding to the information of the data packet receiving situation, and use the adjusted threshold value as the current threshold value. the

In the method for self-adaptive adjustment of the threshold value in the embodiment of the present invention, after obtaining the information of the receiving situation of the data packet, the threshold value is adjusted according to the adjustment mode corresponding to the obtained information, and the adjusted threshold value is used as the current threshold value, Therefore, the adaptive adjustment of the threshold value is realized based on the obtained information on the receiving situation of the data packet, so that the control operation based on the adaptively adjusted threshold value can adapt to the requirements of the wireless environment and improve the communication quality. the

In the embodiment of the present invention, in the above step 101, the information of the data packet receiving situation may include but not limited to the following situations, such as ACK or NACK information, or the average number of retransmissions, or the number of error packets, etc., to obtain these information There can also be various means, which will be described in detail below. the

In the above step 102, the threshold value is adjusted according to the adjustment method corresponding to the information of the data packet receiving situation. The adjustment method may also have multiple methods, and a detailed description will be given below. the

In the embodiment of the present invention, after the above step 102, that is, after the threshold value is adjusted, specific control operation steps such as AMC control or power control may be further included in combination with specific application scenarios. the

Taking AMC control as an example, the specific implementation manners of the feedback mechanism, information acquisition, threshold adaptive adjustment method, and control operation based on adaptive threshold adjustment in the method provided by the embodiment of the present invention are described in detail below. the

1) ARQ/HARQ feedback mechanism

In the Automatic Repeat Request (ARQ, Automatic Repeat Request) technology, the sending end sends an error-detectable data packet to the receiving end, and the receiving end judges whether there is an error in the received data packet according to the coding rules after receiving it, and passes The feedback information feeds back the judgment result to the sending end, and the sending end resends the data packet that the receiving end considers to be wrong according to the judgment result in the feedback information to the receiving end until the receiving end thinks it is correct. the

HARQ technology is an extension based on the above-mentioned ARQ technology. The receiving end first decodes, corrects, and merges the received data packets to recover the data packets. If the errors in the data packets can be corrected, it accepts the data packet and sends The terminal feeds back acknowledgment (ACK, Acknowledgment) information, otherwise it feeds back negative acknowledgment (NACK, NegativeAcknowledgment) information for the data packet to the sending end, and the sending end will retransmit the error data packet. Therefore, compared with the ARQ technology, the HARQ technology adds an error correction function. the

2) Information Statistics

Based on the ARQ/HARQ feedback mechanism selected in the embodiment of the present invention, the information of obtaining data packet reception may include but not limited to: the total number of sent data packets, or the number of correctly sent data packets, or the number of feedback after sending each data packet The number of times of ACK information and NACK information, or the number of retransmission times of each data packet, etc. It can be understood that the acquisition of the information on the receiving situation of the data packet is not limited to the above listed ones, and other information different from the above listed ones can be obtained according to actual needs. the

The information obtained above can also be used to calculate other statistical information useful for subsequent adaptive adjustment of the threshold value, such as the average number of retransmission times or the number of error packets. Among them, the average number of retransmissions is defined by the following formula:

Average retransmission times = increased retransmission times between two statistics / total number of data packets sent between two statistics. the

The number of retransmissions increased between two statistics in the above formula refers to the number of retransmissions of data packets between two statistics, which may include the total number of retransmissions of several data packets. The average number of retransmissions means that between the two statistics in the above formula, the number of retransmissions of the current data packet is averaged with the number of retransmissions of the previous or several previous data packets to obtain the average number of retransmissions. The specific number of statistical data included can be specifically determined according to the actual situation. When the number is selected to be large, the impact of burst interference can be avoided, and when the number is selected to be small, it has better sensitivity to channel quality changes. Based on the application of the average number of retransmissions, it is also possible to record the data frame number corresponding to the obtained information while obtaining the information, which is beneficial to more flexibly checking whether the current statistical data has met the predetermined number. For example, after the current statistics start, through the recorded data frame number, check whether the received data meets the number of statistical data every n data frames. If it is satisfied, the average number of retransmissions can be calculated. The above n can be based on Different values need to be determined. the

If the NACK information of a data packet has reached the maximum number of retransmissions N, it means that the receiving end has received N wrong data packets, and because the sending end judges that the data packet has reached the maximum number of retransmissions, it will not send it again. According to this The error of the data packet can be known by the information, so the number of error packets can be defined by the following formula: the number of error packets=the number of data packets whose number of NACK times reaches the maximum number of retransmissions. Correspondingly, the number of correctly received data packets=the number of data packets whose NACK times do not reach the maximum number of retransmissions. the

3) Threshold value adaptive adjustment method

Divide the AMC control into M MCS levels, each level corresponds to an MCS mode, and the levels are expressed as MCS ₁ , MSC ₂ , ...MCS _M from low to high, and the AMC control corresponding to each MCS level The threshold values are respectively T(1), T(2), . . . T(M). Selecting a certain level of MCS mode means that the sending end needs to perform data transmission according to the modulation and coding mode specified in the MCS mode during data transmission.

In the embodiment of the present invention, the threshold adaptive adjustment methods may include the following three types:

① Adaptively adjust the threshold value according to ACK information or NACK information. The maximum number of times, the adjustment step size δ _UP and the adjustment step size δ _{Down are} preset, and adaptive threshold adjustment is performed according to ACK information or NACK information. FIG. 2 shows the flow of this adjustment method. When the NACK feedback information appears for the first time in a certain data packet, the continuous error counting of the data packet starts, and the accumulation can start from 0. The process shown in Figure 2 includes:

Step 201: Count ACK or NACK information. the

Step 202: Judging whether the statistical information is NACK information, if yes, proceed to step 203, otherwise directly execute step 205. the

Step 203: Determine whether the continuous error count corresponding to the NACK information reaches the preset maximum number of times, if yes, continue to execute step 204, otherwise directly execute step 205. the

Step 204: Raise the AMC thresholds T(1), T(2), ... T(M) corresponding to each level by an adjustment step δ _UP , and end the adaptive adjustment of the thresholds process.

Step 205: Decrease the AMC threshold values T(1), T(2), . . . T(M) corresponding to each level by a step size δ _Down .

After the above step 204 or step 205 is completed, the adaptively adjusted AMC thresholds corresponding to each MCS level can be obtained, and the adjusted thresholds are used as the current thresholds. the

The above is aimed at the situation where the receiving end only receives one data packet at a time. Assuming that there is a situation where the receiving end receives several data packets at a time, then perform steps 201 to 203 according to the above method for different data packets. If these several data packets If the continuous statistics count of NACK information of one data packet in the packet reaches the preset maximum number of times, step 204 is executed after step 203 . the

② Adaptively adjust the threshold value according to the average number of retransmissions. Preset the number of target retransmissions, the adjustment step size δ _UP and the adjustment step size δ _Down , and adaptively adjust the threshold value according to the calculated average number of retransmissions. Figure 3 shows the flow of this adjustment method, which includes :

Step 301: Count the average number of retransmissions. the

Step 302: Obtain the target number of retransmissions, determine whether the calculated average number of retransmissions is higher than the target number of retransmissions, if yes, continue to execute step 303, otherwise directly execute step 304. the

Step 303: Increase the AMC control thresholds T(1), T(2), . . . T(M) corresponding to each level by an adjustment step δ _UP , and end the process.

Step 304: Decrease the AMC control thresholds T(1), T(2), . . . T(M) corresponding to each level by an adjustment step δ _Down .

Similarly, after the above step 303 or step 304 is completed, the adaptively adjusted AMC thresholds corresponding to each MCS level can be obtained, and the adjusted thresholds are used as the current thresholds. the

③ Adaptively adjust the threshold value according to the current number of error packets and the current number of correct data packets. You can set the target value of the number of error packets, the increase step size and the decrease step size. When there are currently error packets, the threshold value will be increased by a set increase step size. When there is no error packet, the threshold value will be decreased by a set decrease step Long, if there is no data transmission at present, it will neither increase nor decrease, and keep the threshold value unchanged. the

For the above implementation manner, a preferred implementation manner can be adopted. The target value of the number of error packets is set to PER_Target, and the adjustment step is Step_size, and the unit is dB. If there is currently an error packet, calculate a larger step size increase based on Step_size, if there is currently no error packet, calculate a smaller step size decrease based on Step_size, if no data packet is transmitted, neither increase nor decrease, maintain the threshold The value remains unchanged, that is, in this preferred embodiment, the raising step size and the lowering step size are calculated in real time according to the adjustment step size, the current number of error packets or the current number of correct data packets. The following pseudo code can be used to describe the process of adaptively adjusting the threshold value in this preferred embodiment using the current number of error packets and the current number of correct data packets. Assume that an adaptive adjustment of the AMC control threshold is performed at each moment, where i represents the current moment, i-1 represents the previous moment at time i, T_target(i) represents the threshold value corresponding to time i, and Step_up represents the step size of the lift value, Step_down indicates the reduced step value, Bad_Packet_Num indicates the current number of error packets, and Good_Packet_Num indicates the current number of correct data packets. the

IF No Data Packet; no data packet

Step_size is 0; the step size will not be increased or decreased when there is no data packet

T_target(i)=T_target(i-1); the threshold value at time i is equal to the threshold value at time i-1

ELSE IF ERRPR The number of Packet/PDU is greater than 0; there is an error packet

Step_up=Bad_Packet_Num(Step_size-PER_target*Step_size); raise the step size

T_target(i)=T_target(i-1)+Step_up; the threshold value at time i is equal to the threshold value at time i-1 plus the step size of the lift

ELSE; the number of data packets without error packets

     Step_down = Good_Packet_Num*PER_target*Step_size; reduce the step size

T_target(i)=T_target(i-1)-Step_down; the threshold at time i is equal to the threshold at time i-1 minus the reduced step size

Fig. 4 is a schematic diagram of the above-mentioned method for adaptively adjusting the threshold value using the current number of error packets and the number of correct data packets, wherein the horizontal axis represents the time, the vertical axis represents the threshold value adjustment value, and the G mark marked on the horizontal axis reduces the step Long, B indicates the lifting step size, and N indicates no operation. Fig. 5 shows the above-mentioned flow of the method for using the number of error packets to adjust the adaptive threshold, the flow includes:

Step 501: Count the current number of error packets and the current number of correct data packets. the

Step 502: Obtain the target value of the number of error packets. the

Step 503: Judging whether there is data packet transmission at present, if not, then execute step 504, otherwise execute 505. the

Step 504: Set the step value to 0, and then execute step 508. the

Step 505: Determine whether the current number of error packets is greater than 0, that is, whether there is currently an error packet, if not, execute step 506, otherwise directly execute step 507. the

Step 506: Calculate the step value to be reduced, and then execute Step 508. the

Step 507: Calculate the step size to be lifted. the

Step 508: According to the calculated step value, calculate the current AMC threshold value corresponding to each level. the

After the above step 508, the adjusted AMC threshold can be obtained. the

Three threshold value adaptive adjustment methods are introduced above, and different threshold value adjustment methods can be used to obtain information about different data packet reception conditions. The threshold value is adjusted according to the adjustment method corresponding to the obtained information, and the adjusted threshold value is used as the current threshold value, thereby realizing adaptive adjustment of the threshold value based on the information of the received data packet received, so that The control operation based on the self-adaptive adjustment threshold value can adapt to the requirements of the wireless environment and improve the communication quality. the

④ AMC control

Assuming that the AMC control is divided into 1~M MCS levels, the AMC control threshold corresponding to level i is T(i), and the value of i is from 1 to M. According to the physical CINR measurement value, different MCS methods can be selected. . If the physical CINR measurement value satisfies T(i)<=CINR<T(i+1), then T(i) is used as the AMC threshold value, and the corresponding MCS(i) is selected as the MCS mode; if the physical CINR measurement value satisfies CINR <=T(1), select T(1) as the AMC threshold value, and select the corresponding MCS(1) as the MCS mode; if the physical CINR measurement value satisfies CINR>=T(M), select T(M) as AMC threshold value, the corresponding MCS(M) is selected as the MCS mode. the

After the new MCS mode is selected, the coded modulator at the sending end can be controlled to use the new MCS mode to send data packets to the receiving end. the

Taking the WIMAX system as a specific application scenario, two specific examples of the downlink AMC control implemented by the BS and the MS in the embodiment of the present invention are given below. the

6 is a flow chart of the first specific example of the method provided by the embodiment of the present invention. In this specific example, the downlink AMC control implemented by the BS is described, and the MCS level is also divided for the AMC control. Each level corresponds to an AMC threshold value . The process shown in Figure 6 includes:

Step 601: the BS sends a downlink data packet to the MS through the air interface. the

Step 602: The MS feeds back ACK or NACK information in ARQ/HARQ to the BS through the air interface according to the reception situation of the downlink data packet. the

Step 603: The MS feeds back the measured value of the downlink physical CINR to the BS. the

Step 604: The BS obtains the ACK or NACK message of ARQ/HARQ according to the need of adaptive adjustment of the threshold value, or obtains the information of the data reception condition such as the average number of retransmissions, or the number of error packets, and performs AMC threshold based on the obtained information. Adaptive adjustment of the value. The acquisition of the above information and the adaptive adjustment of the threshold value are both performed by the BS, and the specific implementation methods can be the same as those described above. When the information acquisition is implemented, only one of the methods needs to be adopted, that is, Can. the

Step 605: The BS selects the MCS mode by using the adaptively adjusted AMC threshold value combined with the physical CINR measurement value fed back by the MS. the

After this step, when the BS sends a downlink data packet to the MS next time, it will use the modulation and coding method specified in the selected MCS method, and at the same time inform the MS of the selected MCS method, so that when the MS receives the downlink data packet, It can be decoded according to the MCS method. The BS sends the downlink data packet and the MCS method can be realized through the downlink bandwidth allocation description (DL-MAP, Downlink band width allocation Map) message in the existing protocol. the

The above step 602 and step 603 do not have a strict sequence relationship, and may also be performed simultaneously. the

The first specific example shown in FIG. 6 above describes the downlink AMC control implemented by the BS. It can be understood that the method provided by the embodiment of the present invention can also be applied to the scenario of uplink AMC control. In the scenario of uplink AMC control, the MS first sends uplink data packets to the BS through the air interface, and then the BS obtains information about data reception, such as ACK or NACK messages, or the average number of retransmissions, or the number of error packets, etc., and the AMC value threshold Carry out self-adaptive adjustment, combined with the physical CINR measurement value measured by itself to select the desired MCS mode, the MS can be notified of its own uplink bandwidth allocation description (UL-MAP, Uplink band width allocation Map) message through the existing protocol. In the desired MCS mode, the MS sends data packets according to the modulation and coding method specified by the MCS method specified by the BS, that is, the MS executes the modulation and coding method specified in the MCS method selected by the BS. the

The first specific example of the method for self-adaptive adjustment of the threshold value in the embodiment of the present invention, for the uplink or downlink AMC control implemented by the BS, based on the obtained information about the receiving situation of the data packet, the adaptive adjustment of the AMC threshold value is realized, thereby The AMC control based on the adaptively adjusted AMC threshold value can adapt to the requirements of the wireless environment and improve the communication quality. the

Fig. 7 is a flow chart of the second specific example of the method provided by the embodiment of the present invention. In this specific example, the downlink AMC control implemented by the MS is described, and the MCS level is also divided for the AMC control, and each level corresponds to an AMC threshold value . The process shown in Figure 7 includes:

Step 701: the BS sends a downlink data packet to the MS through the air interface. the

Step 702: The MS obtains ARQ/HARQ feedback information according to the reception of downlink data packets, obtains ACK or NACK information, or the average number of retransmissions, or the number of error packets, etc., and adaptively adjusts the AMC control threshold, Likewise, the specific ways of acquiring the above information and adaptively adjusting the threshold value can be the same as those described in detail above, and only one of the ways needs to be adopted in the specific realization of the information acquiring. the

Step 703: The MS selects a desired MCS mode by using the adaptively adjusted AMC threshold value combined with the physical CINR measurement value. the

Step 704: The MS feeds back ACK or NACK information to the BS through the air interface. the

Step 705: The MS encodes the expected MCS mode into an effective CINR, and feeds it back to the BS through the air interface. The effective CINR can be fed back to the BS through a channel quality indication feedback channel (CQICH, Channel Quality Information Channel) or other methods. the

Step 706: The BS transmits the data packet directly according to the MCS mode carried by the effective CINR fed back by the MS. the

The above step 704 and step 705 do not have a strict sequence relationship, and can also be performed at the same time. the

Although the above-mentioned specific examples all take AMC control as an example, it can be understood that in other control operations that need to use the threshold value, the adaptive adjustment method of the threshold value can still use the above-mentioned specific example. way of listing. For example, in power control in a WIMAX system, the above-mentioned threshold value may be an inner-loop power control threshold value, and power control may be performed according to the inner-loop power control threshold value. the

The second specific example of the method for self-adaptive adjustment of the threshold value in the embodiment of the present invention is aimed at the downlink AMC control implemented by the MS, based on the information of the received data packet received, the self-adaptive adjustment of the AMC threshold value is realized, so that the AMC threshold value based on The AMC control performed by the adaptively adjusted AMC threshold value can adapt to the requirements of the wireless environment and improve communication quality. the

Those of ordinary skill in the art can understand that all or part of the steps in the methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, and when the program is executed , including the following steps:

Obtain information about the reception of data packets;

The threshold value is adjusted according to the adjustment manner corresponding to the information on the receiving situation of the data packet, and the adjusted threshold value is used as the current threshold value. Wherein, the storage medium may be ROM, RAM, magnetic disk or optical disk and so on. the

Figure 8 is a schematic diagram of a device for adaptive adjustment of a threshold value according to an embodiment of the present invention, the device includes:

The information obtaining module is used to obtain the information of the receiving situation of the data packet. the

The adjustment module is configured to adjust the threshold value according to the adjustment method corresponding to the information on the receiving situation of the data packet acquired by the information acquisition module, and use the adjusted threshold value as the current threshold value. the

The device for adaptively adjusting the threshold value in the embodiment of the present invention, after obtaining the information about the receiving situation of the data packet, adjusts the threshold value according to the adjustment mode corresponding to the obtained information, and uses the adjusted threshold value as the current threshold value, Therefore, the self-adaptive adjustment of the threshold value is realized based on the obtained information of the receiving situation of the data packet, so that the control operation based on the threshold value can adapt to the requirement of the wireless environment and improve the communication quality. the

According to different application scenarios, in the device provided by the embodiment of the present invention, each module may correspond to different divisions, and several specific examples are introduced below. the

1) When the information of the above-mentioned data packet receiving situation is ACK information or NACK information, the above-mentioned adjustment module may include:

The first judging unit is configured to judge whether the information on the receiving situation of the data packet acquired by the information acquiring module is ACK information or NACK information, and obtain a judging result. the

The first adjustment execution unit is configured to reduce the threshold value by a preset adjustment step if the determination result obtained by the first determination unit is ACK information; or, if the determination result obtained by the determination unit is NACK information , and the accumulated number of received NACK information does not reach the preset maximum value, the threshold value is reduced by the preset adjustment step size; or, if the judgment result obtained by the determination unit is NACK information, and the accumulated number of received NACK information When the preset maximum value is reached, the threshold value is raised by a preset adjustment step. the

2) When the above-mentioned data packet reception information is the average number of retransmissions, the above-mentioned information acquisition module includes:

The first execution unit is used to obtain the number of data packet retransmissions increased between two statistics, and the total number of data packets sent between two statistics. the

The first calculation unit is used to divide the number of data packet retransmissions increased between the two statistics obtained by the execution unit by the total number of data packets sent between the two statistics to obtain the average number of retransmissions as the data packet reception situation Information. the

On the basis of the above structure of the information acquisition module, the adjustment module in the device may include:

The second determination unit is configured to determine whether the average number of retransmissions obtained by the first calculation unit is higher than a preset target number of retransmissions, and obtain a determination result. the

The second adjustment execution unit is configured to increase the threshold value by a preset adjustment step if the judgment result obtained by the second judgment unit is that the average number of retransmissions is higher than the preset target number of retransmissions; or the judgment unit The obtained determination result is that the average number of retransmissions is lower than the preset target number of retransmissions, and the threshold value is reduced by a preset adjustment step. the

3) When the information of the above-mentioned data packet reception situation is the current number of error packets and the current number of correct data packets, the information acquisition module in the device may include:

The second execution unit is used to count the number of times of NACK information of the data packet. the

The second calculation unit is configured to use the number of data packets whose number of NACK information counted by the second execution unit reaches the preset maximum number of retransmissions as the current number of error packets; The number of data packets of retransmission times is used as the current correct number of data packets. the

On the basis of the structure of the above-mentioned information acquisition module, preset the adjustment step size Step_size and the target value PER_Target of the number of error packets, and set the current number of error packets as Bad_Packet_Num and the current number of correct data packets as Good_Packet_Num, then the step size Step_up=Bad_Packet_Num when lifting ×(Step_size-PER_Target×Step_size), the step size when reducing is Step_down=Good_Packet_Num×PER_Target×Step_size; the above-mentioned adjustment module can include:

The third judging unit is used to judge whether there is currently data packet transmission and whether there is currently an error packet, and obtain a judging result. the

The third adjustment execution unit is configured to add 0 to the threshold value if the determination result of the third determination unit is that there is currently no data packet transmission; or, if the determination result of the third determination unit is that there is currently data packet transmission, And when there is an error packet, the threshold value is increased by the step size during the increase; or, if the determination result of the third determination unit is that there is currently a data packet transmission, and there is no error packet, the threshold value is reduced by the The step size when lowering. the

The device for self-adaptive adjustment of the threshold value in the embodiment of the present invention, according to the information of different data packet reception conditions, further structural design is carried out on the modules in the device, based on the obtained information of the data packet reception conditions, according to the corresponding different adjustment methods, The adaptive adjustment of the threshold value is realized, so that the control operation based on the adaptively adjusted threshold value can adapt to the requirement of the wireless environment and improve the communication quality. the

In the case of the different structures of the modules in the above-mentioned 1)-3), the threshold value adjusted by the adjustment module can be used for AMC control including more than one MCS level, and the threshold value includes a value corresponding to each MCS level threshold value. the

On this basis, it is assumed that the MCS grade includes grades 1 to M, and the current threshold corresponding to the i grade is T(i); the device also includes:

The MCS mode selection module is used to select the MCS mode of the i level when the physical CINR measurement value is greater than or equal to T(i), but less than T(i+1); when the physical CINR measurement value is less than or equal to T(1), Select the MCS mode of the first level; when the physical CINR measurement value is greater than or equal to T(M), select the MCS mode of the Mth level. the

Considering the situation of downlink AMC control, if the device is located in the base station, the device also includes:

The first transceiver module is used to send downlink data packets and the MCS mode selected by the MCS mode selection module to the terminal, receive ACK information or NACK information fed back by the terminal, and physical CINR measurement values. the

Considering the situation of uplink AMC control, if the device is located in the base station, the device also includes:

The second transceiver module is configured to receive the uplink data packet sent by the terminal, and send the MCS mode selected by the MCS mode selection module to the terminal. the

Measurement module for measuring physical CINR measurements. the

Still considering the situation of downlink AMC control, if the device is located in the terminal, the device also includes:

The third transceiver module is configured to receive the downlink data packet sent by the base station, encode the MCS mode selected by the MCS mode selection module into an effective CINR and send it to the base station. the

The device for self-adaptive adjustment of the threshold value in the embodiment of the present invention, for uplink or downlink AMC control, supplements the modules that can be further included in the device, based on the obtained information about the reception of data packets, according to the corresponding adjustment method, realizes The AMC threshold value is adaptively adjusted, so that the AMC control operation based on the adaptively adjusted AMC threshold value can adapt to the requirements of the wireless environment and improve communication quality. the

It can be seen from the above description that the device provided by the embodiment of the present invention can be applied in different scenarios, either at the transmitting end or at the receiving end. FIG. 9 shows that the device of the embodiment of the present invention is applied in an ARQ or HARQ system schematic diagram. In FIG. 9 , the device for adaptively adjusting the threshold value according to the embodiment of the present invention is located at the sending end, and its working mode is exactly the same as that of the described device at the sending end, and will not be repeated here. the

To sum up, the above are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention. the

Claims (11)

1. A method for threshold value adaptive adjustment, characterized in that the preset adjustment step size Step_size and the target value PER_Target of the number of error packets, and setting the current number of error packets as Bad_Packet_Num and the current number of correct data packets as Good_Packet_Num, then raise The step size is Step_up=Bad_Packet_Num×(Step_size-PER_Target×Step_size), and the reduction step size is Step_down=Good_Packet_Num×PER_Target×Step_size; the method includes: Obtaining information on the reception of data packets, including: counting the number of negative acknowledgment NACK information of the data packets, taking the number of data packets whose number of times the NACK information reaches the preset maximum number of retransmissions as the number of error packets, and counting the number of times of the NACK information that has reached the preset maximum number of retransmissions. The number of data packets reaching the preset maximum number of retransmissions is taken as the number of correct data packets; Adjust the threshold value, including: if there is no data packet transmission, increase the threshold value by 0; or if there is data packet transmission, and there is currently an error packet, increase the threshold value by the above-mentioned lifting step; or if there is data packet transmission, And currently there is no error packet, and the threshold value is reduced by the step size; Use the adjusted threshold as the current threshold. 2. The method according to claim 1, wherein the threshold value is used for adaptive modulation and coding (AMC) control, and the AMC control includes more than one modulation and coding mode control MCS level, and the threshold value includes the corresponding The threshold value of each MCS level; The adjusting the threshold value is adjusting the threshold value of each MCS level. 3. The method according to claim 2, wherein, assuming that the MCS grade includes grades 1 to M, the current threshold value corresponding to the i grade is T(i), and the threshold value is adjusted to be After the adjusted threshold is used as the current threshold, it further includes: When the physical carrier-to-interference-noise ratio CINR measurement value is greater than or equal to T(i), but less than T(i+1), select the i-th level MCS mode; or When the physical CINR measurement value is less than or equal to T(1), choose the MCS method of level 1; or When the physical CINR measurement value is greater than or equal to T(M), the MCS mode of the Mth level is selected. 4. The method according to claim 3, wherein, before obtaining the information of the data packet receiving situation, it further comprises: the base station sends the downlink data packet to the terminal, the base station receives ACK information or NACK information fed back from the terminal, and physical CINR measurements; After the selection of the MCS mode, it further includes: when the base station sends a downlink data packet to the terminal next time, sending the selected MCS mode to the terminal through a downlink bandwidth allocation description DL-MAP message. 5. The method according to claim 3, further comprising: the terminal receiving the downlink data packet sent by the base station; After the selection of the MCS mode, it further includes: the terminal encodes the selected MCS mode into an effective CINR and sends it to the base station. 6. The method according to claim 3, further comprising: the base station receiving the uplink data packet sent by the terminal; The base station measures the physical CINR measurement value; After the selection of the MCS mode, it further includes: the base station sends the selected MCS mode to the terminal through an uplink bandwidth allocation description UL-MAP message. 7. A device for threshold value adaptive adjustment, characterized in that the preset adjustment step size Step_size and the target value PER_Target of the number of error packets, and setting the current number of error packets as Bad_Packet_Num and the current number of correct data packets as Good_Packet_Num, then raise The step size is Step_up=Bad_Packet_Num×(Step_size-PER_Target×Step_size), and the reduction step size is Step_down=Good_Packet_Num×PER_Target×Step_size; the device includes: The information acquisition module includes: a second execution unit for counting the number of negative acknowledgment NACK information of the data packet; a second calculation unit for counting the number of NACK information counted by the second execution unit to a preset maximum number of retransmissions The number of data packets is used as the current number of error packets, and the number of data packets for which the number of times of the NACK information does not reach the preset maximum number of retransmissions is used as the current number of correct data packets; The adjustment module includes: a third determination unit, configured to determine whether there is currently a data packet transmission, and whether there is an error packet currently, to obtain a determination result; a third adjustment execution unit, configured to determine if the determination result of the third determination unit If there is currently no data packet transmission, add 0 to the threshold value; or if the determination result of the third determination unit is that there is currently data packet transmission and there is an error packet, increase the threshold value by the lifting step; or if the The determination result of the third determining unit is that there is currently data packet transmission and there is no packet error, and the threshold value is reduced by the reduction step; the adjusted threshold value is used as the current threshold value. 8. The device according to claim 7, wherein the threshold value adjusted by the adjustment module is used for AMC control comprising more than one MCS level, and the threshold value includes a value corresponding to each MCS level Threshold value; Assume that the MCS level includes levels 1 to M, and the current threshold value corresponding to the i-th level is T(i); the device also includes: The MCS mode selection module is used to select the MCS mode of the i-th level when the physical CINR measurement value is greater than or equal to T(i) but less than T(i+1); or, when the physical CINR measurement value is less than or equal to T(1) , select the first-level MCS mode; or, when the physical CINR measurement value is greater than or equal to T(M), select the M-th level MCS mode. 9. The device according to claim 8, further comprising: The first transceiver module is configured to send downlink data packets and the MCS mode selected by the MCS mode selection module to the terminal, receive ACK information or NACK information fed back by the terminal, and receive physical CINR measurement values fed back by the terminal. 10. The device according to claim 8, further comprising: The second transceiver module is used to receive the uplink data packet sent by the terminal, and send the MCS mode selected by the MCS mode selection module to the terminal; Measurement module for measuring physical CINR measurements. 11. The device of claim 8, further comprising: The third transceiver module is configured to receive the downlink data packet sent by the base station, encode the MCS mode selected by the MCS mode selection module into an effective CINR and send it to the base station.

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