QC-LDPC码的编码和译码程序

%QC-LDPC主程序 clear all clc %矩阵初始化 disp('请输入QC-LDPC矩阵的相关参数：'); disp('IEEE802.16e中QC-LDPC码的码长有如下19个：'); disp('576、672、768、864、960、1056、1152、1248、1344'); disp('1440、1536、1632、1728、1824、1920、2016、2112、2208、2304'); CodeLength=input('QC-LDPC码字的长度(默认576)：'); if isempty(CodeLength) CodeLength=576; end CodeRate=input('QC-LDPC码的码率(默认值：0.5)：'); if isempty(CodeRate) CodeRate=1/2; end [qcH,Hb]=QCLDPCBaseH(CodeLength,CodeRate); [row,col]=size(qcH); [rowb,colb]=size(Hb); block=CodeLength/colb; NewsLength=CodeRate*CodeLength;%待编码信息的长度 fprintf(' 单位信息长度为:%d\n', NewsLength); %待编码数据 InputDataNum=input('输入单位信息的数量(默认值：100):'); if isempty(InputDataNum) InputData=randi((0:1),1,100*NewsLength); InputDataNum=100; else InputData=randi((0:1),1,InputDataNum*NewsLength); end CodeNum=InputDataNum; disp('高斯白噪声信道模型输入：0'); channel = input('请输入相应的数值：'); if isempty(channel) channel=0; %AWGN case end disp('程序运行中，请稍候') SNRMAX=3;%调试信噪比的最大值 SNRdb=(1:0.5:SNRMAX); SNRLength=length(SNRdb); ITERNum=[10 20 50];%译码的迭代次数 lengthiter=length(ITERNum); %BPSKErrNum=zeros(1,SNRLength);%未编码错误码字数 BPSKBitErrNum=zeros(1,SNRLength);%未编码错误比特数 %DecodeErrNum=zeros(lengthiter,SNRLength);%译码错误码字数 DecodeBitErrNum=zeros(lengthiter,SNRLength);%译码错误比特数 OutputData=zeros(lengthiter,InputDataNum*NewsLength); %%%%%%%%%%%%%%%%% CODE=[]; Path=8;LFONum=32;TimeStep=1/2700; Speed=18; for snri=1:SNRLength %SNR为信噪比 snr=SNRdb(snri); j=1; for i=1:CodeNum PerData=zeros(1,NewsLength); PerData(1,:)=InputData((j-1)*NewsLength+1:j*NewsLength); j=j+1; %编码 PerCode=QCEncode(PerData,qcH,Hb); %%%%%%%%%%%%%%%%%%%%%%%%%%5 %if snr==3 %CODE(i,:)=PerCode; %end %经过信道 SNR=10^(snr/10); sigma=sqrt(1/(2*CodeRate*SNR)); Noise=randn(size(PerCode))*sigma; if channel==1 %AIQ=MultiUncorRayleighFading(Speed,Path,LFONum,TimeStep,cols*block); %AIQ=Dopplertest(Speed,Path,cols*block); AIQ=Rician_fading(snr,colb*block,1); ChannelNoise=AIQ.*(-(2*PerCode-1))+Noise; elseif channel==2 AIQ=Rician_fading(-inf,colb*block,1); ChannelNoise=AIQ.*(-(2*PerCode-1))+Noise; elseif channel==3 AIQ=JakesFading(colb*block); ChannelNoise=AIQ.*(-(2*PerCode-1))+Noise; else ChannelNoise=(-(2*PerCode-1))+Noise; end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% OutputChannel=ChannelNoise; %OutputChannel=ChannelNoise*LC; %OutputCode=AWGN(OutputChannel); %BPSKErrNum(1,snri)=BPSKErrNum(1,snri)+ErrCode; %BPSKBitErrNum(1,snri)=BPSKBitErrNum(1,snri)+sum(abs(OutputCode-PerCode)); %BP译码 ErrDecode=zeros(1,lengthiter); for iternum=1:lengthiter iter=ITERNum(iternum);%迭代次数 %%%%%%%%%%%%%%%%%%%%%%5%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % if channel==0 BPOutputdecode=LDPCDecode(OutputChannel,rowb,colb,block,qcH,sigma,iter); % else % BPOutputdecode=QCUMPBPBased(OutputChannel,row,col,qcH,sigma,iter); % end ErrDecode(1,iternum)=sum(abs(BPOutputdecode-PerCode)); %%%%%%%%%%%%%%%%%%%%%%%%%%% %if snr==3&&iternum==4 % CODE(i,:)=decode; %end end DecodeBitErrNum(:,snri)=DecodeBitErrNum(:,snri)+ErrDecode'; %ErrDecode %%%%%%%%%%%%%%%%%%%%%% %if sum(ErrDecode)>100 % PerCode % break % end %提取信息 %OutputSign=[OutputSign decode(1,NewsLength)]; end %%%%%%%%%%%%%%%%%%%%%%%%%%%% % if sum(ErrDecode)>100 % break % end %OutputData(snri,:)=OutputSign; end x=SNRdb; %yOut=BPSKErrNum/CodeNum; yBPSKBit=BPSKBitErrNum/(InputDataNum*col); %yDec=DecodeErrNum/CodeNum; yBit=DecodeBitErrNum/(InputDataNum*col); % semilogy(x,yBPSKBit,'-s',x,yBit(1,:),'--o',x,yBit(2,:),'--*') semilogy(x,yBit(1,:),'--o',x,yBit(2,:),'--*',x,yBit(3,:),'--s') % legend('未编码BPSK','误码率(迭代次数=10)','误码率(迭代次数=20)') legend('误码率(迭代次数=10)','误码率(迭代次数=20)','误码率(迭代次数=50)') xlabel('信噪比(dB)') ylabel('BER') title('IEEE802.16e标准的QC-LDPC码误码率') grid on %figure %semilogy(x,yBPSKBit,'-s',x,yBit(1,:),'--o',x,yBit(2,:),'--*') %pic=legend('未编码BPSK','误比特率(迭代次数=5)','误比特率(迭代次数=10)') %set(pic,'Location','SouthWest'); %xlabel('信噪比(dB)') %ylabel('BER') %title('Block-LDPC码在多普勒频移下衰落信道的BER性能(v=18km/h)') %title('Block-LDPC码的BER性能') %grid on %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%