Add multi_ch_cal modules, optimize .gitignore.

2023-03-19 11:53:45 +08:00
parent 454606fac2
commit d77ea9315b
212 changed files with 374911 additions and 159 deletions
@@ -0,0 +1,118 @@
+%% File Header/文件说明
+%
+% 调零算法对幅相一致性的要求较高，且 AD9361 多片同步的精度随机性较大，因此需要对
+% AD9361 多片同步误差进行精细校准。采用收发扩频码的方式在校准过程中对两片 AD9361
+% 的两个接收通道进行幅相测量，在接收端使用加法器进行非相干相关峰累积，累积 N 个
+% 符号后出峰，根据相关峰的高度差和相位差，在接收端对信号的幅度和相位进行补偿。
+%
+clc; clear; close all;
+%% initial system parameters/初始系统参数
+rng(0);
+Eb_N0 = 30; % energy per bit to noise power spectral density ratio
+interp = 8; % interpolation factor
+SNR = 10*log10(2/interp) + Eb_N0; % signal-to-noise power ration
+channelNum = 2;
+deltaAmp = 1-(2*rand-1)*0.05;     % random amplitude error, range: [0.95,1.05]
+deltaAngRad = (2*rand-1)*pi;      % random phase error, range: [-pi,pi]
+deltaAngDeg = deltaAngRad/pi*180;
+angleInit = 20/pi*180;
+
+% standard pn sequence
+pnSequence = comm.PNSequence('Polynomial','x^7+x^6+1', ...
+  'InitialConditions',[zeros(1,6),1],'SamplesPerFrame',2^7-1);
+PRBS7 = pnSequence();
+PRBS7_polar = 1-2*[PRBS7;0];
+
+chipLen = length(PRBS7_polar);      % pn chip length
+accumSymbolNum = 16;
+totalSymbolNum = accumSymbolNum+1;
+
+randomChipIndex_ch1 = randi(chipLen*interp*2-1)-chipLen*interp;   % random rx chip index
+randomChipIndex_ch2 = randomChipIndex_ch1 + (randi(2*interp-1)-interp);   % random rx chip index
+% randomChipIndex_ch1 = -2;   % random rx chip index
+% randomChipIndex_ch2 = 5;   % random rx chip index
+
+%%
+% 发送信号：方波成型
+seqTx = kron(repmat(PRBS7_polar,totalSymbolNum,1),ones(interp,1));
+
+% 接收信号：随机初始相位，加噪，随机幅度误差，随机相位误差
+seqRx = awgn(seqTx,SNR,'measured').*[1,deltaAmp].*[exp(1i*angleInit),...
+  exp(1i*(angleInit+deltaAngRad))];
+seqRx(:,1) = circshift(seqRx(:,1),randomChipIndex_ch1);
+seqRx(:,2) = circshift(seqRx(:,2),randomChipIndex_ch2);
+
+% 降采样，与 Verilog 实现一样在码片中心采样
+seqRxDown = zeros(chipLen*accumSymbolNum,channelNum,interp);
+
+for i = 0:interp-1
+  % 补偿 Verilog 模块的读数延迟
+  seqRxDown(:,:,i+1) = downsample(seqRx((1:accumSymbolNum*chipLen*interp)+2,:),interp,i);
+end
+
+% 取符号位
+seqRxMsbReal = zeros(size(seqRxDown));
+seqRxMsbImag = zeros(size(seqRxDown));
+seqRxMsbReal(real(seqRxDown)>0) = 1;
+seqRxMsbReal(real(seqRxDown)<0) = -1;
+seqRxMsbImag(imag(seqRxDown)>0) = 1;
+seqRxMsbImag(imag(seqRxDown)<0) = -1;
+
+% 符号位累积
+seqRxMsbRealAccum = zeros(chipLen,channelNum,interp);
+seqRxMsbImagAccum = zeros(chipLen,channelNum,interp);
+
+for i = 0:chipLen-1
+  % PN 码圆周移位，遍历所有 PN 码相位
+  PRBS7_cshift = circshift(repmat(PRBS7_polar,accumSymbolNum,1),-i); % 负号为了和 Verilog 程序对应
+  % 累积，若当前比特与 PN 码相同，结果 +1；否则结果 -1
+  seqRxMsbRealAccum(i+1,:,:) = sum(PRBS7_cshift==seqRxMsbReal)-...
+    sum(PRBS7_cshift~=seqRxMsbReal);
+  seqRxMsbImagAccum(i+1,:,:) = sum(PRBS7_cshift==seqRxMsbImag)-...
+    sum(PRBS7_cshift~=seqRxMsbImag);
+end
+
+seqRxMsbAccum = seqRxMsbRealAccum+1i*seqRxMsbImagAccum;
+
+% 通过相关峰位置判断目标信号位置
+maxPeakIndex = zeros(2,interp);
+
+for i = 1:2
+  for j = 1:interp
+    maxPeakIndex(i,j) = find(abs(seqRxMsbAccum(:,i,j))==max(abs(seqRxMsbAccum(:,i,j))),1); % PN 码相位
+  end
+end
+
+maxPeakIndexDiff = zeros(channelNum,1); % 相位差
+
+for i = 1:channelNum
+  for j = 1:interp
+    if (maxPeakIndex(i,j)==maxPeakIndex(i,1))
+      maxPeakIndexDiff(i) = j;
+    end
+  end
+end
+
+% 以下条件仅对双通道有效
+if (maxPeakIndex(1,1) == maxPeakIndex(2,1))
+  relativeDelay = maxPeakIndexDiff(2) - maxPeakIndexDiff(1);
+  desiredPointIndex = [1,1]+[0,chipLen];
+elseif (mod(maxPeakIndex(1,1)-1,chipLen) == mod(maxPeakIndex(2,1),chipLen))
+  relativeDelay = maxPeakIndexDiff(2) - maxPeakIndexDiff(1) + interp;
+  desiredPointIndex = [1,2]+[0,chipLen];
+elseif (mod(maxPeakIndex(1,1)+1,chipLen) == mod(maxPeakIndex(2,1),chipLen))
+  relativeDelay = maxPeakIndexDiff(2) - maxPeakIndexDiff(1) - interp;
+  desiredPointIndex = [2,1]+[0,chipLen];
+end
+
+% 输入信号累加
+seqRxDownAccum = squeeze(sum(reshape(seqRxDown(:,:,1),128,[],2),2));
+% 取目标位置信号
+desiredPoint = seqRxDownAccum(desiredPointIndex);
+
+ampEst = abs(desiredPoint)./abs(desiredPoint(1));
+angleEst = (angle(desiredPoint) - angle(desiredPoint(1)))/pi*180;
+
+seqRxExport = round([real(seqRx(:,1)),imag(seqRx(:,1)),real(seqRx(:,2)),...
+  imag(seqRx(:,2))]/max(abs(seqRx),[],'all')*(2^11-1));
+writematrix(seqRxExport,'./fine_cal_data.txt');