WO2009074111A1

WO2009074111A1 - Adaptive threshold adjusting method and device

Info

Publication number: WO2009074111A1
Application number: PCT/CN2008/073402
Authority: WO
Inventors: Jun Wang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-12-10
Filing date: 2008-12-09
Publication date: 2009-06-18
Also published as: CN101207461A; CN101207461B

Abstract

An adaptive threshold adjusting method and an adaptive threshold adjusting device, the method includes: acquiring the information about data packet reception (101); adjusting the threshold according to the adjustment manner corresponding to the information about data packet reception, and taking the adjusted threshold as the current threshold (102). The invention can implement adaptive threshold adjustment, and make the control operation based on the threshold to adapt to the requirement of the fast-changing wireless circumstance, and improve the communication quality.

Description

Method and device for adaptively adjusting threshold value

Technical field

The present invention relates to control technology, and in particular, to a method and apparatus for adaptive adjustment of threshold values. Background technique

IEEE (Institute of Electrical and Electronics Engineers) The 802.16e protocol makes it possible to enjoy wireless broadband access services at any time and any place using a single terminal. The World Microwave Interoperability Forum based on the IEEE 802.16e protocol. (WIMAX, Worldwide Interoperability for Microwave Access Forum) has become a hot spot of attention as soon as it emerged. Its key technologies, Hybrid Automatic Repeat Request (HARQ) and Adaptive Modulation and Coding (AMC), enable the WIMAX system to further improve its key features such as speed, throughput and capacity.

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

The following takes the AMC control as an example. The IEEE 802.16e protocol provides the following two ideas for implementing downlink AMC control:

1) AMC control by MS, MS selects the downlink modulation coding mode (MCS, Modulation and Coding Scheme) according to the AMC threshold, and passes the effective carrier interference to noise ratio

(Efficient CINR, Effective Carrier to interference and noise ratio), the value of the MCS mode selected by the BS, and the BS uses the modulation and coding mode specified in the MCS mode selected by the MS for data transmission;

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

The above-mentioned existing protocols only provide the idea of how to use the threshold to perform related control operations. In this idea, the fixed AMC threshold is used, which does not involve the criteria for adaptive adjustment of the threshold, and how to implement it. Adaptive adjustment of threshold values.

The above AMC control is taken as an example to illustrate the implementation of the fixed threshold in the relevant control in the existing scheme, which will result in the control operation based on the fixed threshold not adapting to the requirements of the rapidly changing wireless environment. , reducing the quality of communication.

Summary of the invention

The embodiment of the invention provides a method for adaptively adjusting a threshold value, which can adaptively adjust the threshold value, 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 embodiment of the invention provides a device for adaptively adjusting a threshold value, which can adaptively adjust the threshold value, 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 technical solution of the embodiment of the present invention is implemented as follows:

A method for adaptively adjusting a threshold value, the method comprising:

Obtain information on the reception status of the data packet;

The threshold value is adjusted according to the adjustment method corresponding to the information of the data packet receiving situation, and the adjusted threshold value is used as the current threshold value.

A device for adaptively adjusting a threshold value, the device comprising:

An information acquiring module, configured to obtain information about a data packet receiving situation;

The adjusting module is configured to adjust the threshold according to the information corresponding to the information received by the information acquiring module, and use the adjusted threshold as the current threshold.

It can be seen that, in the method and device for adaptively adjusting the threshold value provided by the embodiment of the present invention, after obtaining the information of the data packet receiving situation, according to the adjustment manner corresponding to the information of the data packet receiving situation, The threshold value is adjusted, and the adjusted threshold value is used as the current threshold value, so that the adaptive adjustment of the threshold value is implemented based on the acquired information of the received data packet, so that the adaptive adjustment threshold is based on the threshold The control operations performed can adapt to the requirements of a rapidly changing wireless environment and improve communication quality.

DRAWINGS

1 is a flowchart of a method for adaptively adjusting a threshold value according to an embodiment of the present invention;

2 is a flowchart of adaptively adjusting threshold values based on ACK and NACK information according to an embodiment of the present invention;

FIG. 3 is a flowchart of adaptive threshold adjustment based on the average number of retransmissions according to an embodiment of the present invention; FIG. 4 is a schematic diagram of adaptively adjusting threshold values based on current packet error number and current correct data packet number according to an embodiment of the present invention; ;

FIG. 5 is a flowchart of adjusting threshold value based on the current number of error packets and the current correct number of data packets according to an embodiment of the present invention;

FIG. 6 is a flowchart of a first specific example of a method for adaptively adjusting threshold values according to an embodiment of the present invention; FIG. 7 is a flowchart of a second specific example of a method for adaptively adjusting threshold values according to an embodiment of the present invention; A schematic structural diagram of an apparatus for adaptively adjusting a threshold value according to an embodiment of the invention;

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

detailed description

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

FIG. 1 is a flowchart of a method for adaptively adjusting a threshold value according to an embodiment of the present invention, where the process includes: Step 101: Acquire information about a data packet receiving situation.

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

The method for adaptively adjusting the threshold value in the embodiment of the present invention, in obtaining information about the reception status of the data packet After that, the threshold value is adjusted according to the adjustment manner corresponding to the obtained information, and 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 acquired information of the data packet receiving situation. Therefore, the control operation based on the adaptive adjustment threshold can adapt to the requirements of the wireless environment and improve the communication quality.

In the embodiment of the present invention, in the foregoing step 101, the information about the data packet receiving situation may include, but is not limited to, a plurality of situations, such as an ACK (Acknowledgement) or a Negative Acknowledgement (NACK, Negative Acknowledgement) information, or an average weight. There are a variety of means for obtaining such information, such as the number of transmissions, or the number of errors, and a detailed description will be given below.

In the above step 102, the threshold value is adjusted according to the adjustment manner corresponding to the information of the data packet receiving situation, and the adjustment manner may also be in various manners, and a detailed description will be given below.

In the embodiment of the present invention, after the step 102 is adjusted, the specific application scenarios are further combined, and the specific control operation steps of the AMC control or the power control may be further included.

The following takes the AMC control as an example to describe in detail the specific implementation manners of the feedback mechanism, the information acquisition, the threshold adaptive adjustment mode, and the control operation based on the adaptive adjustment threshold in the method provided by the embodiment of the present invention.

1) ARQ/HARQ feedback mechanism

In the automatic repeat request (ARQ) technology, the transmitting end sends an error-detectable data packet to the receiving end, and after receiving the data, the receiving end determines whether there is an error in the received data packet according to the encoding rule, and passes the error. The feedback information feeds the judgment result to the transmitting end, and the transmitting end sends the data packet that the receiving end thinks is erroneous to the receiving end according to the judgment result in the feedback information until the receiving end thinks that it is correct.

The HARQ technology is based on an extension of the above ARQ technology. The receiving end recovers the data packet by decoding, correcting, and merging the received data packet first. If the error in the data packet can be corrected, the data packet is accepted and sent. The terminal feeds back the ACK information, otherwise the NACK information for the data packet is fed back to the transmitting end, and the transmitting end performs retransmission of the error data packet. Therefore, HARQ technology is relative to ARQ Technically, error correction has been added.

2) Information statistics

Based on the ARQ/HARQ feedback mechanism selected by the embodiment of the present invention, the information about obtaining the data packet receiving status may include, but is not limited to, the total number of the sent data packets, or the number of correctly sent data packets, or the feedback after sending each data packet. The number of times of ACK information and NACK information, or the number of retransmissions of each data packet, and the like. It can be understood that the information for obtaining the reception status of the data packet is not limited to the above-mentioned several types, and other information different from the above enumeration can be obtained according to actual needs.

It is also possible to calculate other statistical information useful for adaptive adjustment of subsequent threshold values, such as the average number of retransmissions or the number of error packets, by using the information obtained above. The average number of retransmissions is defined by the following equation: Average number of retransmissions = number of retransmissions between two statistics / total number of packets sent between statistics.

The number of retransmissions between the two statistics in the above formula refers to the number of times the packet is retransmitted between the two statistics, which may include the total number of retransmissions of several packets. The average number of retransmissions is 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 previous data packets, and the average number of retransmissions is obtained. The number of statistics included in the specific data can be determined according to the actual situation. When the number of selections is large, the influence of burst interference can be avoided. When the number of selection is small, the sensitivity to channel quality is better. Based on the application of the average number of retransmissions, it is also possible to record the data frame number corresponding to the acquired information while acquiring the information, which is advantageous for checking more flexibly whether the current statistical data has already met the predetermined number. For example, after the current statistics start, check whether the received data has met the number of statistical data by using the recorded data frame number every n data frames. If it is satisfied, the average number of retransmissions can be calculated. The above n can be based on Need to determine different values.

If the NACK information of a certain packet has reached the maximum number of retransmissions N, it indicates that the receiving end has received N times of error packets, and because the transmitting end determines that the data packet has reached the maximum number of retransmissions, it is no longer sent. The packet can be informed of the packet error, so the number of packets can be defined by the following formula: Number of packets = NACK The number of packets that have reached the maximum number of retransmissions. Correspondingly, correct Number of received packets = The number of packets whose number of NACKs did not reach the maximum number of retransmissions.

3) Threshold adaptive adjustment method

The AMC control is divided into M MCS levels, each level corresponds to one MCS mode, and the level is represented as MCS1 and MSC2 MCSM from low to high, and the AMC control threshold corresponding to each MCS level is T(l), respectively. Τ(2) Τ(Μ). When a certain level of MCS mode is selected, it is equivalent to the data transmission when the transmitting end transmits data according to the modulation and coding mode specified by the MCS mode.

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

1 The threshold value is adaptively adjusted according to the ACK information or the NACK information. The preset maximum number of times, the adjustment step size ^ ^5, and the adjustment step size ^^, the adaptive threshold adjustment is performed based on the ACK information or the NACK information, and FIG. 2 shows the flow of the adjustment method. When a packet has the NACK feedback information for the first time, it starts counting statistics of consecutive packets of the packet, which can be accumulated from 0. The process shown in Figure 2 includes:

Step 201: Count ACK or NACK information.

Step 202: Determine whether the statistical information is NACK information. If yes, proceed to step 203; otherwise, directly perform step 205.

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

Step 204: Raise the AMC threshold values T(l) and Τ(2) Τ(Μ) corresponding to each level by one adjustment step length ^ ³ , and end the process of adaptively adjusting the threshold value.

Step 205: Decrease the AMC thresholds T(l) and Τ(2) Τ(Μ) corresponding to each level by one step.

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

The above is for the case where the receiving end receives only one data packet at a time, assuming that there is a receiving end In the case of receiving a plurality of data packets, the steps 201 to 203 are performed according to the above methods for different data packets, respectively, if the number of consecutive NACK information of one of the plurality of data packets reaches the preset maximum number of times. Then, after step 203, step 204 is performed.

2 The threshold value is adaptively adjusted according to the average number of retransmissions. The preset target retransmission times, the adjustment step size ^^, and the adjustment step size ^^ are adaptively adjusted according to the average number of retransmission times. Figure 3 shows the flow of the adjustment method, and the process includes :

Step 301: Count the average number of retransmissions.

Step 302: Obtain the number of retransmissions of the target, and determine whether the calculated average number of retransmissions is higher than the number of retransmissions. If yes, proceed to step 303. Otherwise, go to step 304.

Step 303: Raise the AMC control threshold T(l) Τ(2) Τ(Μ) corresponding to each level by one adjustment step ^ End process.

Step 304: Lower the AMC control thresholds T(l), Τ(2) Τ(Μ) corresponding to each level by one adjustment step

Similarly, after the above step 303 or step 304 is completed, the AMC threshold corresponding to each MCS level after the adaptive adjustment can be obtained, and the adjusted threshold value is taken as the current threshold value.

3 The threshold value is adaptively adjusted according to the current number of packet errors and the current correct number of packets. You can set the target number of the number of packets, the step size and the step size. When there is a current packet error, the threshold is raised by a set step. If there is no packet error, the threshold is lowered by one. Long, if there is no data transmission at present, it will not increase or decrease, and the threshold will remain unchanged.

For the foregoing implementation manner, a preferred implementation manner may be adopted. The target value of the number of error packets is set to PER_Target, and the adjustment step size is Step-size, and the unit is dB. If there is a current packet error, calculate a larger step size according to Step-size. If there is no packet error, calculate a smaller step size according to Step-size. If there is no packet transmission, it will not increase or decrease. Maintaining the threshold value unchanged, that is, in the preferred embodiment, the stepping step and the decreasing step size are based on the adjustment step size, The current number of error packets or the current correct number of packets is calculated in real time. The process of adaptively adjusting the threshold value using the current number of error packets and the current correct number of packets in the preferred embodiment can be described using the following pseudo code. It is assumed that the adaptive adjustment of the AMC control threshold is performed once every time, where i represents the current time, i-1 represents the previous moment of time i, and T_target(i) represents the threshold corresponding to time i, Step_up indicates The step value of the step up, Step_down indicates the reduced step value, Bad_Packet_Num indicates the current number of packets, and Good-Packet-Num indicates the current correct number of packets.

IF No Data Packet; no data packet

Step—size is 0; no step size is raised or no step size when there is no data packet

T target ( i ) = T target ( i-1 ); The threshold at time i is equal to the threshold at time i-1 ELSE IF ERRPR Packet/PDU is greater than 0;

Step_up = Bad_ Packet_um (Step_size - PER- target* Step-size); 4 sets of steps

T target ( i ) = T target ( i-1 ) + Step up; The threshold at time i is equal to the i-1 threshold plus the step size of the lift

ELSE; number of packets without error packets

Step— down = Good— Packet— um *PER— target* Step— size;

T target ( i ) = T target ( i-1 ) - Step down; The threshold at time i is equal to the threshold value at time i-1 minus the step size of reduction

Figure 4 is a schematic diagram of the method for adaptively adjusting the threshold value using the current number of packet errors and the correct number of packets, wherein the horizontal axis represents the time, the vertical axis represents the threshold adjustment value, and the G flag indicated on the horizontal axis is reduced. Long, B identifies the step size, and the N flag has no operation. FIG. 5 shows the above method flow for performing adaptive threshold adjustment using the number of error packets, and the process includes:

Step 501: Count the current number of packet errors and the current correct packet number statistics.

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

Step 503: Determine whether there is currently a data packet transmission, if not, execute step 504, otherwise Execute 505.

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

Step 505: Determine whether the current number of error packets is greater than 0, that is, whether there is a current packet error. If no, go to step 506; otherwise, go to step 507.

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

Step 507: Calculate the step value to be raised.

Step 508: Calculate the current AMC threshold corresponding to each level according to the calculated step value. After the above step 508, the adjusted AMC threshold can be obtained.

The above describes the three types of threshold adaptive adjustment methods, to obtain different data packet receiving situation information, you can use different threshold adjustment methods. Adjusting the threshold according to the adjustment method corresponding to the obtained information, and using the adjusted threshold as the current threshold, thereby adaptively adjusting the threshold based on the acquired information of the received data packet, thereby enabling The control operation based on the adaptive adjustment threshold can adapt to the requirements of the wireless environment and improve communication quality.

4 AMC control

Assume that the AMC control is divided into 1 to M MCS levels. The AMC control threshold of the corresponding level i is T(i), and the value of i ranges from 1 to M. According to the physical CINR measurement value, different MCS modes can be selected. . If the physical CINR measurement satisfies T(i)<=CINR<T(i+l), then T(i) is used as the AMC threshold, and the corresponding MCS (3⁄4 is selected as the MCS mode; if the physical CINR measurement satisfies the CINR< =T(1), then T(l) is selected as the AMC threshold, and the corresponding MCS(l) is selected as the MCS mode. If the physical CINR measurement satisfies CINR>=T(M), T(M) is selected as the AMC. For the threshold value, the corresponding MCS (M) is selected as the MCS mode.

After selecting the new MCS mode, the coded modulator of the transmitting end can be controlled to send a data packet to the receiving end in a new MCS mode.

In the following, the WIMAX system is used as a specific application scenario, and two specific examples of downlink AMC control implemented by the BS and the MS in the embodiment of the present invention are shown.

FIG. 6 is a flowchart of a first specific example of a method according to an embodiment of the present disclosure, 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, and each level corresponds to an AMC threshold. The process shown in Figure 6 includes:

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

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

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

Step 604: The BS acquires an ACK or NACK message of the ARQ/HARQ according to the requirement of adaptive adjustment of the threshold value, or obtains information about the data reception status such as the average number of retransmissions or the number of error packets, and performs an AMC threshold according to the obtained information. Adaptive adjustment of values. The acquisition of the above information and the adaptive adjustment of the threshold are performed by the BS. The specific manner of execution can be the same as that described in the foregoing. When the information is specifically implemented, only one of the methods is needed. Just fine.

Step 605: The BS uses the adaptively adjusted AMC threshold, and then combines the physical CINR measurement value of the MS feedback to select the MCS mode.

After the step of transmitting the downlink data packet to the MS, the BS uses the modulation and coding mode specified by the MCS mode selected above, and simultaneously informs the MS of the selected MCS mode, 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 mode by using the Downlink band width allocation Map (DL-MAP) message in the existing protocol.

The above steps 602 and 603 have no strict sequential relationship, and may be performed simultaneously. The first specific example shown in FIG. 6 described above describes the downlink AMC control implemented by the BS. In the uplink AMC control scenario, the MS first sends an uplink data packet to the BS through an air interface, and then the BS obtains information about the data reception status, such as an ACK or NACK message, or an average number of retransmissions, or a number of error packets, and the AMC value threshold. The adaptive adjustment is performed, and the desired MCS mode is selected according to the physical CINR measurement value measured by itself, and the MS itself can be informed by the existing uplink bandwidth allocation map (UL-MAP) message of the existing protocol. In the desired MCS mode, the MS transmits a data packet according to a modulation and coding scheme defined by the MCS mode specified by the BS, that is, the MS performs a modulation and coding scheme defined in the MCS mode selected by the BS.

The first specific example of the method for adaptively adjusting the threshold value in the embodiment of the present invention, for the uplink or downlink AMC control implemented by the BS, implements adaptive adjustment of the AMC threshold value based on the acquired information of the data packet receiving condition, thereby The AMC control based on the AMC threshold of the adaptive adjustment can adapt to the requirements of the wireless environment and improve the communication quality.

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

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

Step 702: The MS obtains ARQ/HARQ feedback information, obtains ACK or NACK information, or average retransmission times, or the number of error packets according to the receiving condition of the downlink data packet, and adaptively adjusts the AMC control threshold. Similarly, the specific manner of obtaining the above information and adaptively adjusting the threshold value may be the same as the manner specifically described above. When the information is specifically obtained, only one of the methods may be used.

Step 703: The MS uses the adaptively adjusted AMC threshold and then combines the physical CINR measurement to select the desired MCS mode.

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

Step 705: The MS encodes the expected MCS mode into a valid CINR, and feeds back to the BS through an air interface, and can feed back the effective CINR to the BS through a Channel Quality Information Channel (CQICH) or other manner.

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

The above steps 704 and 705 have no strict order relationship and can also be performed simultaneously.

Although the above specific examples are based on the AMC control, it can be understood that in other control operations that require threshold values, the adaptive adjustment of the threshold value can still be made. Use the methods listed in the specific examples above. For example, in the power control in the WIMAX system, the threshold may be an inner loop power control threshold, and power control may be performed according to the inner loop power control threshold.

A second specific example of the method for adaptively adjusting the threshold value in the embodiment of the present invention, for the downlink AMC control implemented by the MS, based on the acquired information of the received data packet condition, adaptively adjusting the AMC threshold value, thereby enabling The AMC control performed by the adaptively adjusted AMC threshold can adapt to the requirements of the wireless environment and improve the communication quality.

Those skilled in the art can understand all or part of the steps in the method of implementing the above embodiments.

The related hardware may be instructed by a program, and the program may be stored in a computer readable storage medium, and when executed, the program includes the following steps:

Obtain information on the reception status of the data packet;

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

FIG. 8 is a schematic diagram of an apparatus for adaptively adjusting a threshold value according to an embodiment of the present invention. The apparatus includes: an information acquiring module, configured to obtain information about a data packet receiving situation.

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

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 respectively introduced below. 1) When the information of the data packet receiving condition is ACK information or NACK information, the foregoing adjusting module may include:

The first determining unit is configured to determine whether the information of the data packet reception status acquired by the information acquiring module is ACK information or NACK information, and obtain a determination result.

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

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

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

a first calculating unit, configured to divide the number of data packet retransmissions between the two statistics obtained by the execution unit, and divide the total number of data packets sent between the two statistics, and obtain the average number of retransmissions as the data packet receiving situation. Information.

On the basis of the foregoing structure of the information acquiring module, the adjusting module in the device may include: a second determining unit, configured to determine whether the average number of retransmissions obtained by the first calculating unit is higher than a preset number of retransmission times, The result of the judgment.

a second adjustment execution unit, configured to: if the determination result obtained by the second determining unit is that the average number of retransmissions is higher than the preset number of retransmissions, the threshold adjustment step is preset; or the determining unit The result of the determination is that the average number of retransmissions is lower than the preset number of retransmissions, and the threshold is decreased by a preset adjustment step.

3) When the information of the data packet receiving condition is the current number of packets and the current number of packets, the information acquiring module in the device may include: The second execution unit is configured to count the number of NACK information of the data packet.

a second calculating unit, configured to use, as the current number of packets, the number of NACK information counted by the second execution unit to reach a preset maximum number of retransmissions; The number of packets of the number of retransmissions is the current correct number of packets.

Based on the structure of the information acquisition module, the preset step size Step-size and the number of error packets PER_Target are preset, and the current number of packet errors is Bad_Packet-Num, and the current correct packet number is Good-Packet. — Num, the step size when uplifting is Step-up=Bad— Packet—Num χ (Step-size - PER—Target x Step-size), and the step size when decreasing is Step-down=Good— Packet— Num χ PER — Target x Step— size; The above adjustment module can include:

The third determining unit is configured to determine whether there is currently a data packet transmission, and whether there is currently a packet error, and the determination result is obtained.

a third adjustment execution unit, configured to: if the determination result of the third determining unit is that there is no current packet transmission, increase the threshold value by 0; or, if the determination result of the third determining unit is that there is currently a data packet transmission, And when there is a packet error, the step value is raised to the threshold when the threshold is raised; or, if the determination result of the third determining unit is that there is currently a packet transmission, and there is no packet error, the threshold value is lowered. The step size when reducing.

The device for adaptively adjusting the threshold value according to the embodiment of the present invention further designs the module in the device according to the information of different data packet receiving conditions, and according to the obtained information of the data packet receiving situation, according to different adjustment modes. The adaptive adjustment of the threshold value is realized, so that the control operation based on the threshold value of the adaptive adjustment can adapt to the requirements of the wireless environment and improve the communication quality.

In the case of the above 1) - 3) different configurations of the modules in the device, the adjustment module adjusted threshold value may be used for AMC control including more than one MCS level, the threshold value including corresponding to each of the MCS levels Threshold.

On the basis of the above, the MCS level includes the levels 1 to M, and the current threshold corresponding to the i-th level is T(i); the device further includes: The MCS mode selection module is configured 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); when the physical CINR measurement value is less than or equal to T(l), The MCS mode of the first level is selected; when the physical CINR measurement value is greater than or equal to T(M), the MCS mode of the Mth level is selected.

Considering the case of the downlink AMC control, if the device is located in the base station, the device further includes: a first transceiver module, configured to send the downlink data packet and the MCS mode selected by the MCS mode selection module to the terminal, and receive the ACK information fed back by the terminal. Or NACK information, and physical CINR measurements.

Considering the uplink AMC control, if the device is located in the base station, the device further includes: a second transceiver module, configured to receive an uplink data packet sent by the terminal, and send the MCS mode selected by the MCS mode selection module to the terminal.

A measurement module for measuring physical CINR measurements.

Still considering the case 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, and encode the MCS mode selected by the MCS mode selection module into a valid CINR to send to the base station.

The device for adaptively adjusting the threshold value in the embodiment of the present invention supplements the module that can be further included in the device for the uplink or downlink AMC control, and implements the information based on the received data packet according to the corresponding adjustment mode. The adaptive adjustment of the AMC threshold value enables the AMC control operation based on the AMC threshold of the adaptive adjustment to adapt to the requirements of the wireless environment and improve the communication quality.

It can be seen from the above description that the device provided by the embodiment of the present invention can be applied to different scenarios, and can be located at the transmitting end or at the receiving end. FIG. 9 shows that the device in the embodiment of the present invention is applied to the ARQ or HARQ system. Schematic diagram. In FIG. 9, the device for adaptively adjusting the threshold value in the embodiment of the present invention is located at the transmitting end, and its working mode is exactly the same as the case where the device described above is located at the transmitting end, and details are not described herein again. In conclusion, the above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A method for adaptively adjusting a threshold value, the method comprising:

Obtain information on the reception status of the data packet;

The threshold value is adjusted according to the adjustment manner corresponding to the information of the data packet receiving situation, and the adjusted threshold value is used as the current threshold value.

2. The method for adaptively adjusting a threshold value according to claim 1, wherein the information of the data packet reception status is an acknowledgement ACK information or a negative acknowledgement NACK information;

The adjusting manner includes: if the information is ACK information, lowering the threshold by a preset adjustment step or

If the information is NACK information, if the accumulated number of the NACK information does not reach the preset maximum value, the preset adjustment step is decreased to the threshold value, otherwise the preset adjustment step is raised to the threshold value.

The method for adaptively adjusting the threshold value according to claim 1, wherein the information of the data packet receiving condition is an average number of retransmissions;

The information for obtaining the data packet receiving condition is: using the number of data packet retransmissions between the two statistics, and dividing by the total number of data packets sent between the two statistics, obtaining the average number of retransmissions.

The method for adaptively adjusting the threshold value according to claim 3, wherein the adjusting manner comprises:

If the average number of retransmissions is higher than the preset number of retransmissions, the preset adjustment step of the threshold is raised or

If the average number of retransmissions is lower than the preset number of retransmissions, the threshold is lowered by a preset adjustment step.

The method for adaptively adjusting the threshold value according to claim 1, wherein the information of the data packet receiving situation is the current number of packet errors and the current correct number of packets;

The information for obtaining the data packet reception status is:

Counting the number of NACK information of the data packet, and reaching the preset maximum retransmission of the number of NACK information The number of data packets of the number of times is used as the number of error packets;

The number of data packets whose number of times of the NACK information does not reach the preset maximum number of retransmissions is used as the correct number of packets.

The method for adaptively adjusting the threshold value according to claim 5, wherein the preset adjustment step size_size and the number of error packets target value PER_Target are set, and the current error packet number is Bad-Packet. — Num, the current correct number of packets is Good—Packet—Num, then step-up=Bad—Packet—Num χ (Step—size - PER—Target x Step—size), step by step is Step-do Wn=Good— Packet— um ^x PER—Target ^x Step— size;

The adjustment manner includes: if there is no data packet transmission, the threshold value is increased by 0; or

If there is a packet transmission, and there is currently a packet error, the threshold is raised to the threshold; or if there is a packet transmission, and there is currently no packet error, the threshold is lowered by the threshold.

The method for adaptively adjusting threshold values according to any one of claims 1 to 6, wherein the threshold value is used for adaptive modulation and coding AMC control, and the AMC control includes one or more modulation codes. Controlling an MCS level, the threshold value including a threshold value corresponding to each of the MCS levels;

The threshold is adjusted to adjust the threshold of each MCS level.

The method for adaptively adjusting the threshold value according to claim 7, wherein the MCS level includes levels 1 to M, and the current threshold corresponding to the i-th level is T(i), After adjusting the threshold value and using the adjusted threshold as the current threshold, it further includes:

When the physical carrier interference-to-noise ratio CINR measurement is greater than or equal to T(i) but less than T(i+1), the MCS mode of the i-th level is selected; or

When the physical CINR measurement value is less than or equal to T(l), the MCS mode of the first level is selected; or when the physical CINR measurement value is greater than or equal to T(M), the MCS mode of the Mth level is selected.

The method for adaptively adjusting the threshold value according to claim 8, wherein the obtaining the information of the data packet reception situation further comprises: the base station transmitting the downlink data packet to the terminal, and the base station receiving the ACK from the terminal feedback Information or NACK information, and physical CINR measurements; After the MCS mode is selected, the method further includes: when the base station sends the downlink data packet to the terminal, sending the selected MCS mode to the terminal by using a downlink bandwidth allocation description DL-MAP message.

The method for adaptively adjusting the threshold value according to claim 8, wherein the obtaining the information of the data packet receiving situation further comprises: receiving, by the terminal, a downlink data packet sent by the base station; after the selecting the MCS mode The method further includes: the terminal coding the selected MCS mode into a valid CINR and transmitting the same to the base station.

The method for adaptively adjusting the threshold value according to claim 8, wherein the obtaining the information of the data packet reception situation further comprises: the base station receiving the uplink data packet sent by the terminal; and the base station measuring the physical CINR measurement value. ;

The selecting the MCS mode further includes: the base station transmitting, by the uplink MCS mode, the UL-MAP message to the terminal by using the uplink bandwidth allocation description.

12. A device for adaptively adjusting a threshold value, the device comprising:

The adjusting module is configured to adjust the threshold according to the adjustment manner corresponding to the information of the data packet receiving status acquired by the information acquiring module, and use the adjusted threshold as the current threshold.

The apparatus for adaptively adjusting the threshold value according to claim 12, wherein the information of the data packet receiving condition is ACK information or NACK information; and the adjusting module includes:

a first determining unit, configured to determine whether the information of the data packet receiving status acquired by the information acquiring module is ACK information or NACK information, and obtain a determination result;

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

The device for adaptively adjusting the threshold value according to claim 12, wherein the information of the data packet receiving condition is an average number of retransmissions; and the information acquiring module comprises: a first execution unit, configured to obtain an increased number of data packet retransmissions between two statistics, and a total number of data packets sent between the two statistics;

And a first calculating unit, configured to divide the number of data packet retransmissions between the two statistics obtained by the execution unit, and divide the total number of data packets sent between the two statistics to obtain an average number of retransmissions.

The apparatus for adaptively adjusting a threshold value according to claim 14, wherein the adjustment module comprises:

a second determining unit, configured to determine whether the average number of retransmissions obtained by the first calculating unit is higher than a preset number of retransmissions, and obtain a determination result;

a second adjustment execution unit, configured to: if the result of the determination by the second determining unit is that the average number of retransmissions is higher than the preset number of retransmissions, the threshold is raised to a preset adjustment step; or, if The determination result obtained by the determining unit is that the average number of retransmissions is lower than the preset number of retransmissions, and the threshold is decreased by a preset adjustment step.

The apparatus for adaptively adjusting the threshold value according to claim 12, wherein the information of the data packet reception status is the current number of error packets and the current correct data packet number; and the information acquisition module includes:

a second execution unit, configured to count the number of NACK information of the data packet;

The apparatus for adaptively adjusting the threshold value according to claim 16, wherein the preset adjustment step size_size and the number of error packets target value PER_Target are set, and the current error packet number is Bad-Packet. — Num, the current correct number of packets is Good—Packet—Num, then step-up=Bad—Packet—Num χ (Step—size - PER—Target x Step—size), step by step is Step-do Wn=Good— Packet— um ^x PER—Target ^x Step— size;

The adjustment module includes:

a third determining unit, configured to determine whether there is currently a data packet transmission, and whether there is currently a packet error, Determining the result of the judgment;

a third adjustment execution unit, configured to increase the threshold value by 0 if the determination result of the third determining unit is that no data packet is currently transmitted; or

If the determination result of the third determining unit is that there is currently a packet transmission, and there is a packet error, the threshold is raised to the threshold; or

If the result of the determination by the third determining unit is that there is currently a packet transmission and there is no packet error, the threshold value is decreased by the reduced step size.

The apparatus for adaptively adjusting a threshold value according to any one of claims 12 to 17, wherein the threshold value adjusted by the adjustment module is used for AMC control including more than one MCS level, the door The limit value includes a threshold value corresponding to each of the MCS levels;

The MCS level includes a level 1 to M, and the current threshold corresponding to the i-th level is T(i); the device further includes:

The MCS mode selection module is configured 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(l) When the MCS mode of the first level is selected, or when the physical CINR measurement value is greater than or equal to T(M), the MCS mode of the Mth level is selected.

The device for adaptively adjusting the threshold value according to claim 18, wherein the device further comprises:

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

The apparatus for adaptively adjusting the threshold value according to claim 18, wherein the apparatus further comprises:

a second transceiver module, configured to receive an uplink data packet sent by the terminal, and send the MCS mode selected by the MCS mode selection module to the terminal;

A measurement module for measuring physical CINR measurements.

The apparatus for adaptively adjusting a threshold value according to claim 18, wherein the apparatus further comprises: