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CN-122027419-A - Method and system suitable for comprehensive tester to analyze Wi-Fi OFDMA multi-user performance

CN122027419ACN 122027419 ACN122027419 ACN 122027419ACN-122027419-A

Abstract

The invention provides a method and a system suitable for a comprehensive tester to analyze Wi-Fi OFDMA multi-user performance, wherein the method comprises the following steps: a Client field splitting step, a Client channel estimating step, a Client residual frequency offset estimating step, a Client equalizing step, a Client pilot tracking step, a Client demodulating step, a first judging step, a Client result analyzing step, a second judging step and a comprehensive signal analyzing step, after the comprehensive tester uses the method, the comprehensive tester can support the measurement requirements of the DUT transmitted to the clients through OFDMA, evaluate various receiving indexes of each access Client and the receiving indexes of the whole DUT, and meet the signal analysis requirements of the comprehensive tester on multi-user OFDMA access of the DUT equipment.

Inventors

  • JIANG WU

Assignees

  • 深圳市极致汇仪科技有限公司

Dates

Publication Date
20260512
Application Date
20251226

Claims (9)

  1. 1. The method for analyzing Wi-Fi OFDMA multi-user performance by using the comprehensive tester is characterized by comprising the following steps of: Splitting the fields of all clients based on the information analyzed by the SIG field, acquiring the information of the frequency band of each Client, establishing an index for each Client, and enabling the clients to be user terminals accessed to the AP network; channel estimation of clients, namely sequentially carrying out channel estimation processing on each Client; The Client residual frequency offset estimation is used for calculating residual frequency offset on own frequency bands of all clients; the Client balancing, namely carrying out residual frequency offset compensation on clients based on residual frequency offset on own frequency bands of the clients; Acquiring the integral phase offset of all pilot frequency sub-carriers and the phase offset of all pilot frequency sub-carriers relative to the sub-carrier serial numbers, carrying out phase tracking compensation, and then updating a channel estimation value for the next OFDM symbol; the Client demodulation, which is to demap the subcarrier constellation points with the phase tracking compensation to obtain the standard reference position after demapping each subcarrier constellation point; A first judging step of judging whether the OFDM symbols of the Client are all demapped, if not, returning to the Client residual frequency offset estimating step of the next OFDM symbol, and if so, executing the Client result analyzing step; Analyzing the Client result, namely after traversing all OFDM symbols, calculating the signal receiving performance of the Client; Judging whether all Client result analysis is completed or not, if not, returning to the Client channel estimation step of the next Client, and if so, executing the comprehensive signal analysis step; and (3) comprehensive signal analysis, namely calculating the performance index of the whole received signal and analyzing the performance of the whole received signal.
  2. 2. The method for analyzing Wi-Fi OFDMA multi-user performance by using a comprehensive tester according to claim 1, wherein in the Client field splitting step, frequency domain subcarriers of each split Client are: acquiring MU frames of data frames of multiple clients, wherein the total number of the analyzed MU frame symbols is S, the index subscript is S, and the MU frames are shared The index subscript of each Client is First, the The number of subcarriers of each Client is Index subscript is Carrier number of First, the The pilot subcarrier number of each Client is Index subscript is Carrier number of , For the serial number of the Client, For the number of sub-carriers, Frequency domain subcarriers of MU frame are denoted as The pilot subcarriers are denoted as The frequency domain subcarriers of the training sequence HE/EHT-STF field are represented as The frequency domain subcarriers of the training sequence HE/EHT-LTF field are represented as The reference signal of the training sequence HE/EHT-STF field is denoted as The reference signal of the training sequence HE/EHT-LTF field is denoted as Wherein Client index OFDM symbol index Subcarrier index , 。
  3. 3. The method for analyzing Wi-Fi OFDMA multiuser performance by using a comprehensive tester according to claim 2, wherein in the Client channel estimation step, the analysis is performed one by one until all clients are detected, and the specific processing procedure is as follows: acquisition of reference signals for the HE/EHT-STF field of a training sequence And a reference signal of a training sequence HE/EHT-LTF field And frequency domain subcarriers corresponding to the HE/EHT-STF field of the received training sequence And frequency domain subcarriers of a training sequence HE/EHT-LTF field , Channel estimation based on training sequence HE/EHT STF field The method comprises the following steps: , Channel estimation based on training sequence HE/EHT-LTF field The method comprises the following steps: , By using The number of active subcarriers representing the training sequence HE/EHT STF field, Indicating the number of effective subcarriers of the HE/EHT-LTF field of the training sequence, the total number of effective subcarriers The final channel estimation calculation formula is: 。
  4. 4. The method for analyzing Wi-Fi OFDMA multi-user performance by using a comprehensive tester according to claim 3, wherein in the step of combining the Client residual frequency offset, The training sequence HE/EHT STF field and HE/EHT-LTF field differ by one OFDM symbol, the time interval of one OFDM symbol being The channel variation between them estimates the residual frequency offset, which is calculated according to the following formula : 。
  5. 5. The method for analyzing Wi-Fi OFDMA multi-user performance by comprehensive tester according to claim 4, wherein in the Client balancing step, The residual frequency offset changes along with the change of the symbol sequence s, and the channel state of the OFDM symbol s=1 is that Channel state after 2 nd is , Residual frequency offset compensation is carried out on clients, and frequency domain subcarrier information after compensation The calculation process is as follows: , Equalized frequency domain subcarrier information That is, the recovered transmission information has a calculation formula: 。
  6. 6. the method for analyzing Wi-Fi OFDMA multi-user performance of claim 4 wherein the Client pilot tracking and demodulating steps are performed by: (1) The center carrier position of the Client is calculated, Equalized frequency domain information The peer-to-peer representation of the pilot portion involved is Based on the demodulation information, the pilot reference value is expressed as The center carrier position of the Client is denoted as , (2) By using Representing the overall phase offset of all pilot subcarriers, For the phase offsets of all pilot subcarrier related subcarrier sequence numbers, the calculation method is as follows: , (3) The phase tracking compensates and updates the channel estimate, Frequency domain information for post-phase tracking compensation The method comprises the following steps: , updating the channel estimation value to be used for the next OFDM symbol, and updating the channel estimation value after updating The method comprises the following steps: , (4) The mapping is performed in such a way that, According to the modulation information of the Client analyzed by the SIG field, a constellation diagram of a corresponding modulation mode is obtained, the frequency domain information is expressed as a constellation point mode, the constellation point demapping mode is a standard reference position with minimum Euclidean distance between the constellation point and a standard reference position constellation diagram, and after demapping, the frequency domain information is obtained The obtained reference position is recorded as 。
  7. 7. The method for analyzing Wi-Fi OFDMA multiuser performance by comprehensive tester according to claim 6, wherein in the Client result analysis step, the Client signal receiving performance evaluation index comprises error vector magnitude EVM and final frequency offset And/or phase differences between OFDM symbols, wherein, The difference vector magnitude is calculated as: Final frequency offset The calculation formula of (2) is as follows: , sampling CFO compensated data, phase difference between OFDM symbols The calculation formula of (2) is as follows: , wherein, For the frequency offset and compensation amount exhibited over the entire bandwidth.
  8. 8. The method for analyzing Wi-Fi OFDMA multiuser performance by a comprehensive tester according to claim 7, wherein in the comprehensive signal analyzing step, the performance index includes an overall signal receiving quality, an overall final frequency offset, an overall final sampling offset, a power and/or a power amplification factor of Client, wherein the overall signal receiving quality The calculation formula of (2) is as follows: , Final frequency offset The calculation formula of (2) is as follows: , Final sampling bias The calculation formula of (2) is as follows: , Total power of all clients obtained by using voltage value of received signal Calculating the power of each Client The calculation process is as follows: , Power amplification factor of Client The calculation formula of (2) is as follows: , Wherein, the Is the first Client (S) The sum of the powers of the channel estimation subcarriers, Is the first Client (S) The power average value of the channel estimation sub-carriers of (c), The sum of the powers of the subcarriers is estimated for all Client channels, The power average of the subcarriers is estimated for all Client channels.
  9. 9. A system adapted for use in a comprehensive tester for analyzing Wi-Fi OFDMA multi-user performance, for implementing the method adapted for use in a comprehensive tester for analyzing Wi-Fi OFDMA multi-user performance of any of claims 1-8, comprising: The Client field splitting module is used for splitting the fields of each Client based on the information analyzed by the SIG field, acquiring the information of the frequency band where each Client is located, establishing an index for each Client, and enabling the Client to be a terminal accessed to the AP network; the Client channel estimation module is used for sequentially carrying out channel estimation processing on each Client; The Client residual frequency offset estimation module is used for calculating residual frequency offset on own frequency bands of all clients; The Client balancing module is used for carrying out residual frequency offset compensation on clients based on residual frequency offset on own frequency bands of the clients; The Client pilot tracking module is used for acquiring the integral phase offset of all pilot subcarriers and the phase offset of all pilot subcarriers relative to subcarrier serial numbers, carrying out phase tracking compensation, and then updating a channel estimation value for the next OFDM symbol; The Client demodulation module is used for demapping the subcarrier constellation points subjected to phase tracking compensation to obtain standard reference positions after demapping of the subcarrier constellation points; the first judging step module is used for judging whether the OFDM symbols of the Client are all demapped; The Client result analysis module is used for calculating the signal receiving performance of the Client after traversing all OFDM symbols; the second judging module is used for judging whether all Client result analysis is completed or not; And the comprehensive signal analysis module is used for calculating the performance index of the whole received signal and analyzing the performance of the whole received signal.

Description

Method and system suitable for comprehensive tester to analyze Wi-Fi OFDMA multi-user performance Technical Field The invention relates to a comprehensive tester performance analysis technology, in particular to a method and a system suitable for analyzing Wi-Fi OFDMA multi-user performance by a comprehensive tester. Background Physical layer data transmission in an 802.11 system is based on PPDU (PHYSICAL LAYER Protocol Data Unit) data units, i.e., uplink and downlink user transmissions are communicated by data packets containing a combination of data information for multiple users. For the transmitting end of the 802.11ax/be downlink OFDMA (Orthogonal Frequency-Division Multiple Access, orthogonal frequency division multiple access) system, after AP (Acess Point) has completed association with multiple users, the AP transmits signals to multiple users simultaneously. Considering a basic service set scenario consisting of one AP, K users in an 802.11 ax-based wireless local area network (wireless local area network, WLAN), the total bandwidth B of a channel is divided into N RUs, and the 802.11ax supports the combined division of RU of different sizes in order to make scheduling multi-user transmission more flexible, as shown in fig. 1, channel resources are allocated to users horizontally in time and channel resources are allocated to users vertically in frequency band. The comprehensive tester measures signals sent by the AP, the general mode is a mode for measuring the whole bandwidth allocated to one user, the 802.11 protocol starts to evolve into a multi-user OFDMA mode, when the comprehensive tester measures OFDMA multi-users, radio frequency indexes of all users need to be split, in the analysis process, a part of information is mixed together, and a part of signals are separated, so that the measurement mode of the comprehensive tester which is generally used for single user is not applicable. Fig. 2 is a frame format of 802.11 ax and 802.11 be supporting OFDMA transmission, and when multi-user transmission is performed, the frame format is shared by a plurality of users before HE-STF/EHT-STF field, and needs to be used for resolving common frequency offset, common sampling offset and compensating, after HE-STF/EHT-STF field, each user is independent from each other in frequency domain, and needs to calculate frequency offset and sampling offset independent of each user and compensate, and phase tracking becomes different according to pilot frequency in Data field, and final measurement index needs to integrate common part and independent part, thus providing new challenges for comprehensive measurement of the tester, and therefore, a method capable of analyzing OFDMA multi-user is needed. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a method and a system suitable for a comprehensive tester to analyze Wi-Fi OFDMA multi-user performance, which can simultaneously measure various receiving indexes of clients and the whole receiving indexes of the DUTs, wherein the AP for sending information is called the DUT, and a user terminal for receiving information is called Clinet for convenience in description. The invention is suitable for a method for analyzing Wi-Fi OFDMA multi-user performance by a comprehensive tester, which comprises the following steps: Splitting the fields of all clients based on the information analyzed by the SIG field, acquiring the information of the frequency band of each Client, establishing an index for each Client, and enabling the clients to be user terminals accessed to the AP network; channel estimation of clients, namely sequentially carrying out channel estimation processing on each Client; The Client residual frequency offset estimation is used for calculating residual frequency offset on own frequency bands of all clients; the Client balancing, namely carrying out residual frequency offset compensation on clients based on residual frequency offset on own frequency bands of the clients; Acquiring the integral phase offset of all pilot frequency sub-carriers and the phase offset of all pilot frequency sub-carriers relative to the sub-carrier serial numbers, carrying out phase tracking compensation, and then updating a channel estimation value for the next OFDM symbol; the Client demodulation, which is to demap the subcarrier constellation points with the phase tracking compensation to obtain the standard reference position after demapping each subcarrier constellation point; A first judging step of judging whether the OFDM symbols of the Client are all demapped, if not, returning to the Client residual frequency offset estimating step of the next OFDM symbol, and if so, executing the Client result analyzing step; Analyzing the Client result, namely after traversing all OFDM symbols, calculating the signal receiving performance of the Client; Judging whether all Client result analysis is completed or not, if not, returning