今天乐乐来给大家分享一些关于systemview仿真眼图方面的知识吧，希望大家会喜欢哦

1、function output_frame = demodulation1(input_modu, index)% demodulation for IEEE802.11a% Input: input_modu, complex values representing constellation points% index% Output: output_frame, output bit stream (data unit is one bit)% In this version, increase the quatilization levels into 8.% note: Matlab index starts from 1Q_length=length(input_modu);Q_length=length(input_modu);QAM_input_I = real(input_modu);QAM_input_Q = imag(input_modu);output_frame = zeros(1,length(input_modu)*index);switch indexcase 1,BPSK_Demodu_I = [0 1]; %f(m)=(m+1)/2 + 1, so I=-1 ---> 1, I=1 ---> 2idx = find(QAM_input_I>1);QAM_input_I(idx) = 1;idx = find(QAM_input_IQAM_input_I(idx) = -1;output_frame = BPSK_Demodu_I(round((QAM_input_I+1)/2) + 1);case 2,QPSK_Demodu_IQ = [0 1]; %f(m)=(m+1)/2 + 1, so I=-1 ---> 1, I=1 ---> 2idx = find(QAM_input_I>1);QAM_input_I(idx) = 1;idx = find(QAM_input_IQAM_input_I(idx) = -1;idx = find(QAM_input_Q>1);QAM_input_Q(idx) = 1;idx = find(QAM_input_QQAM_input_Q(idx) = -1;output_frame(1:2:end) = QPSK_Demodu_IQ(round((QAM_input_I+1)/2) + 1);output_frame(2:2:end) = QPSK_Demodu_IQ(round((QAM_input_Q+1)/2) + 1);case 3,mapping=[3+i 1+i -3+i -1+i -3-i -1-i 3-i 1-i];remapping=[0 0 0;0 0 1;0 1 0;0 1 1;1 0 0;1 0 1;1 1 0;1 1 1].';a=ones(1,8);for j=1:Q_lengthb = mapping-input_modu(j)*a;[gk k1]=min(abs(b).^2);output_frame((1+(j-1)*3):(3+(j-1)*3))=remapping((1+3*(k1-1)):(3+3*(k1-1)));endcase 4,QAM_16_Demodu_IQ = [0 1 3 2]; %f(m)=(m+3)/2 + 1, so I=-3 ---> 1, I=1 ---> 3idx = find(QAM_input_I>3);QAM_input_I(idx) = 3;idx = find(QAM_input_IQAM_input_I(idx) = -3;idx = find(QAM_input_Q>3);QAM_input_Q(idx) = 3;idx = find(QAM_input_QQAM_input_Q(idx) = -3;tmp = round((QAM_input_I+3)/2) + 1;output_frame(1:4:end) = bitget(QAM_16_Demodu_IQ(tmp),2);output_frame(2:4:end) = bitget(QAM_16_Demodu_IQ(tmp),1);tmp = round((QAM_input_Q+3)/2) + 1;output_frame(3:4:end) = bitget(QAM_16_Demodu_IQ(tmp),2);output_frame(4:4:end) = bitget(QAM_16_Demodu_IQ(tmp),1);case 5,mapping=[5+i 3+i 1+i 5+3*i 3+3*i 1+3*i 3+5*i 1+5*i -5+i -3+i -1+i -5+3*i -3+3*i -1+3*i -3+5*i -1+5*i -5-i -3-i -1-i -5-3*i -3-3*i -1-3*i -3-5*i -1-5*i 5-i 3-i 1-i 5-3*i 3-3*i 1-3*i 3-5*i 1-5*i];remapping=[0 0 0 0 0;0 0 0 0 1;0 0 0 1 0;0 0 0 1 1;0 0 1 0 0;0 0 1 0 1;0 0 1 1 0;0 0 1 1 1;0 1 0 0 0;0 1 0 0 1;0 1 0 1 0;0 1 0 1 1;0 1 1 0 0;0 1 1 0 1;0 1 1 1 0;0 1 1 1 1;1 0 0 0 0;1 0 0 0 1;1 0 0 1 0;1 0 0 1 1;1 0 1 0 0;1 0 1 0 1;1 0 1 1 0;1 0 1 1 1;1 1 0 0 0;1 1 0 0 1;1 1 0 1 0;1 1 0 1 1;1 1 1 0 0;1 1 1 0 1;1 1 1 1 0;1 1 1 1 1].';a=ones(1,32);for j=1:Q_lengthb = mapping-input_modu(j)*a;[gk k1]=min(abs(b).^2);output_frame((1+(j-1)*5):(5+(j-1)*5))=remapping((1+5*(k1-1)):(5+5*(k1-1)));endcase 6,QAM_64_Demodu_IQ = [0 1 3 2 6 7 5 4]; %f(m)=(m+7)/2 + 1, so I=-7 ---> 1, I=1 ---> 5idx = find(QAM_input_I>7);QAM_input_I(idx) = 7;idx = find(QAM_input_IQAM_input_I(idx) = -7;idx = find(QAM_input_Q>7);QAM_input_Q(idx) = 7;idx = find(QAM_input_QQAM_input_Q(idx) = -7;tmp = round((QAM_input_I+7)/2) + 1;output_frame(1:6:end) = bitget(QAM_64_Demodu_IQ(tmp),3);output_frame(2:6:end) = bitget(QAM_64_Demodu_IQ(tmp),2);output_frame(3:6:end) = bitget(QAM_64_Demodu_IQ(tmp),1);tmp = round((QAM_input_Q+7)/2) + 1;output_frame(4:6:end) = bitget(QAM_64_Demodu_IQ(tmp),3);output_frame(5:6:end) = bitget(QAM_64_Demodu_IQ(tmp),2);output_frame(6:6:end) = bitget(QAM_64_Demodu_IQ(tmp),1);end太多了，你自己研究研究．。

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