gusucode.com > wlan工具箱matlab源码程序 > wlan/wlanexamples/helperInterpretLSIG.m
function [MCS,PSDULength,numRxSamples] = helperInterpretLSIG(recLSIGBits,sr) % helperInterpretLSIG Interprets recovered L-SIG bits % % [MCS,PSDULENGTH,NUMRXSAMPLES] = helperInterpretLSIG(RECLSIGBITS,SR) % returns the modulation and coding scheme, PSDU length and number of % samples within the packet given the recovered L-SIG bits and sample % rate in Hertz. % Copyright 2015 The MathWorks, Inc. %#codegen % Rate and length are determined from bits rate = double(recLSIGBits(1:3)); length = double(recLSIGBits(5+(1:12))); % MCS rate table for 802.11a R = wlan.internal.nonHTRateSignalBits(); MCS = find(all(bsxfun(@eq,R(1:3,:),rate)))-1; PSDULength = bi2de(length.'); % Get the indices for the Non-HT data field (assuming 20MHz bandwidth) cfgNonHT = wlanNonHTConfig('MCS',MCS,'PSDULength',PSDULength); nonHTDataInd = wlanFieldIndices(cfgNonHT,'NonHT-Data'); % Calculate the number of samples given the actual sampling rate numRxSamples = double(nonHTDataInd(2))*sr/20e6; end