Files
FAR_CS/basic/narrow_signal_model_sample.m
2024-07-22 21:17:49 +08:00

88 lines
2.7 KiB
Matlab
Executable File

function [s_T, A] = narrow_signal_model_sample(FAR_N)
FAR_M = 1;
global c f_c N N_wide B ranges_wide betas_wide FIGURE numP f_s N_high T_r T_p TEST method;
pulse_number = FAR_N;
single_pulse_length = N;
all_pulse_length = single_pulse_length * pulse_number;
pulse_width = N_high;
delta_f = 0;
delta_r = T_p * c / 2;
delta_v = c / (2 * f_c * FAR_N * T_r);
ranges = (0: FAR_M - 1) * delta_r;
velos = (0: FAR_N - 1) * delta_v;
delays = 2 * ranges / c;
t_single = (0: 1/f_s: T_p-1/f_s)';
t = (0: 1/f_s: FAR_N * T_r-1/f_s)';
s_T = zeros(length(t), 1);
T_p_N = floor(T_p * f_s);
T_r_N = floor(T_r * f_s);
freqs = zeros(FAR_N, 1);
for i = 1: FAR_N
C_n = floor(rand() * FAR_M);
freqs(i) = f_c + C_n * delta_f;
% freqs(i) = f_c + i * delta_f;
end
for i = 1: FAR_N
N_l = (i - 1) * T_r_N + 1;
N_r = (i - 1) * T_r_N + T_p_N;
s_T(N_l:N_r) = exp(1j * 2 * pi * freqs(i) * t_single);
end
% echo
s_R = zeros(length(s_T), FAR_M, FAR_N);
s_D = zeros(length(s_T), FAR_M, FAR_N);
for range_idx = 1: FAR_M % R
r = ranges(range_idx);
for doppler_idx = 1: FAR_N % D
v = velos(doppler_idx);
f_n = freqs(doppler_idx);
for pulse_idx = 1: FAR_N % N
nT_r = (pulse_idx - 1) * T_r;
rr = r + v * nT_r;
delay = 2 * rr / c;
t_l = delay + nT_r;
N_l = max(1, round(t_l * f_s) + 1);
N_r = N_l + T_p_N - 1;
s_D(N_l: N_r, range_idx, doppler_idx) = exp(-1j * 2 * pi * f_n * (2 / c) * (r + v * (nT_r + t_single)));
end
end
end
% Sampling
A = zeros(FAR_N, FAR_N * FAR_M);
for range_idx = 1: FAR_M % R
for doppler_idx = 1: FAR_N % D
index = (doppler_idx - 1) * FAR_M + range_idx;
for pulse_idx = 1: FAR_N % N
t_sample = delays(range_idx) + T_p + (pulse_idx - 1) * T_r;
A(pulse_idx, index) = s_D(round(t_sample * f_s), range_idx, doppler_idx);
end
end
end
if 1 == 0
Lambda = 1:10;
x_wide = zeros(N_wide, 1);
x_wide(Lambda) = 1;
n_wide = randn(length(s_T_FAR), 1) * 0.01;
y = A_wide * x_wide;
y_noise = y + n_wide;
x_hat = recovery(A_wide, y_noise, method);
figure(1);
subplot(211); plot(abs(x_wide));
subplot(212); plot(abs(x_hat));
figure(2);
subplot(311); plot(real(A_wide * x_wide));
subplot(312); plot(real(A_wide * x_hat));
subplot(313); plot(real(A_wide * (x_wide - x_hat)));
end