Add Example

2024-11-11 16:32:53 +08:00
parent a2cb6d1825
commit 29ae9585f9
56 changed files with 4029 additions and 0 deletions
@@ -0,0 +1,72 @@
+% PRF: pulse repetition frequency
+% B: bandwidth
+% fs: sampling rate
+% D: duty ratio
+% gamma: compression ratio
+
+% A: chirp matrix
+% signal_t: transmitting beam
+
+
+function [ A, signal_t ] = generate_chirp_mtx(PRF, B, fs, D, gamma, sign_mid)
+
+    % parameters
+    if nargin < 5
+        gamma = 0.5;
+    end
+    if nargin < 6
+        sign_mid = 0;
+    end
+    Tr = 1 / PRF;
+    Tp = Tr * D;
+    K = B / Tp;
+    
+    % generate_signal
+    N = Tr * fs;
+    N_high = Tp * fs;
+    N_mtx = round(N / gamma);
+    
+    signal_t  = zeros(1, N);
+    for i = 1: N_high
+        tp = i * (1 / fs) - sign_mid * N_high / fs / 2;
+        signal_t(1, i) = exp(1j * 2 * pi * 0.5 * K * tp .^ 2);
+    end
+
+    signal_t_2fs  = zeros(1, N_mtx);
+    for i = 1: round(N_high / gamma)
+        tp = (i+1) * (1 / fs / 2) - sign_mid * N_high / fs / 2;
+        signal_t_2fs(1, i) = exp(1j * pi * K * tp .^ 2);
+    end
+    
+    % generate chirp matrix
+    A = generate_matrix_by_signal2fs(transpose(signal_t_2fs));
+
+end
+
+
+% generate chirp matrix when gamma=0.5
+function [ mtx ] = generate_matrix_by_signal2fs(signal)
+
+    mtx = [];
+    l = round(length(signal) / 2);
+    temp1 = signal(1:2:end);
+    temp2 = circshift(signal(2:2:end), 1);
+    if length(temp2) ~= length(temp1)
+        temp2 = [temp2; 0];
+    end
+    
+    for i = 1:l
+        t1 = circshift(temp1, i-1);
+        t2 = circshift(temp2, i-1);
+        if i - 1 > 0
+            t1(1:i - 1,1) = 0;
+        end
+        if i - 1 > 0
+            t2(1:i - 1,1) = 0;
+        end
+        mtx = [mtx,t1,t2];
+    end
+    
+end
+
+