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基于CLEAN算法的杂波抑制Matlab仿真实现

news 2026/5/12 20:59:44

%% 清杂波抑制仿真程序
% 参数设置
clear; clc; close all;%% 1. 参数配置
c = 3e8;          % 光速(m/s)
B = 1e6;          % 带宽(Hz)
fc = 5e9;         % 载频(GHz)
lambda = c/fc;    % 波长(m)
SNR = 10;         % 信噪比(dB)
CNR = 30;         % 杂波信杂比(dB)
N_pulse = 128;    % 脉冲数
PRF = 1000;       % PRF(Hz)
Nr = 64;          % 阵元数
theta_s = 30;     % 目标角度(度)
theta_c = 0;      % 杂波角度(度)%% 2. 信号生成
% 生成目标信号
t = 0:1/PRF:1/PRF*(N_pulse-1);
tau = (theta_s - theta_c)*lambda/(2*Nr); % 波束形成延迟
s = exp(1j*2*pi*fc*t' + 1j*pi*B*t.^2/2); % 线性调频信号% 生成杂波信号
clutter = exp(1j*2*pi*fc*t' + 1j*pi*B*t.^2/2) .* ...exp(1j*2*pi*(theta_c*lambda/(2*Nr))*Nr/2*(1:Nr)');% 添加噪声
noise = (randn(size(s)) + 1j*randn(size(s))) / sqrt(2);
rx = s + 10^(-SNR/20)*noise + 10^(-CNR/20)*clutter;%% 3. CLEAN算法实现
function clean_signal = clean_algorithm(rx, num_iterations)[Nr, N_pulse] = size(rx);clean = zeros(size(rx));residual = rx;for iter = 1:num_iterations% 峰值检测[~, idx] = max(abs(residual));max_pos = ind2sub(size(residual), idx);# 构建模型信号model = zeros(size(residual));model(max_pos(1), max_pos(2)) = residual(max_pos(1), max_pos(2));# 更新清洁信号clean = clean + model;# 更新残差residual = residual - model;end
end%% 4. 信号处理
% 传统FFT处理
fft_rx = fft(rx, [], 2);
fft_clean = fft(clean_algorithm(rx, 10), [], 2);% 距离-多普勒处理
fd = (-Nr/2:Nr/2-1)' * PRF / Nr;
range = (0:N_pulse-1) * c/(2*B);% 清洁算法处理
clean_data = clean_algorithm(rx, 10);%% 5. 结果可视化
figure;
subplot(2,2,1);
imagesc(range, fd, abs(fft_rx));
title('原始信号RD谱'); xlabel('距离(m)'); ylabel('多普勒(Hz)');
colorbar;subplot(2,2,2);
imagesc(range, fd, abs(fft_clean));
title('FFT滤波后RD谱'); xlabel('距离(m)'); ylabel('多普勒(Hz)');
colorbar;subplot(2,2,3);
imagesc(range, fd, abs(clean_data));
title('CLEAN算法RD谱'); xlabel('距离(m)'); ylabel('多普勒(Hz)');
colorbar;% 性能指标计算
SNR_clean = 10*log10(mean(abs(clean_data(:)).^2)/mean(abs(residual(:)).^2));
CNR_clean = 10*log10(mean(abs(clean_data(:)).^2)/mean(abs(noise(:)).^2));%% 6. 性能评估
disp(['CLEAN算法处理后SNR提升: ', num2str(SNR_clean-SNR), ' dB']);
disp(['CLEAN算法处理后CNR提升: ', num2str(CNR_clean-CNR), ' dB']);

关键模块说明

1. 信号生成模块

目标信号：生成线性调频信号，包含目标角度信息
杂波模型：采用分布式杂波模型，包含角度扩展特性
噪声添加：添加复高斯噪声，控制信噪比和杂波信杂比

2. CLEAN算法实现

function clean_signal = clean_algorithm(rx, num_iterations)% 初始化[Nr, N_pulse] = size(rx);clean = zeros(size(rx));residual = rx;% 迭代处理for iter = 1:num_iterations% 峰值检测（带阈值限制）[peak_val, idx] = max(abs(residual(:)));if peak_val < 0.1*max(abs(rx(:)))break; % 提前终止条件end% 构建模型信号[row, col] = ind2sub(size(residual), idx);model = zeros(size(residual));model(row, col) = residual(row, col);% 更新清洁信号clean = clean + model;# 残差更新（带步长因子）residual = residual - 0.5*model; endclean_signal = clean;
end