matlab 求份基于m序列和gold序列的直接序列扩频、解扩频模块系统的代码

以下是基于m序列和gold序列的直接序列扩频、解扩频模块系统的 MATLAB 代码：

% M序列生成函数
function [m_seq] = m_sequence(n, c_init)
% 计算M序列的周期和阶数
m = 2^n - 1;
% 初始化M序列
m_seq = zeros(1, m);
c = zeros(1, n);
c(1) = 1;
for i = 1:m
m_seq(i) = c(n);
new_c = mod(sum(c([1 2 5 7 8 9])), 2);
c = [new_c c(1:n-1)];
end
end

% Gold序列生成函数
function [gold_seq] = gold_sequence(n, c_init1, c_init2)
% 计算Gold序列的周期和阶数
m = 2^n - 1;
% 初始化Gold序列
gold_seq = zeros(1, m);
c1 = zeros(1, n);
c2 = zeros(1, n);
c1(1) = 1;
c2(1) = c_init2;
for i = 1:m
gold_seq(i) = mod(sum(and(c1, c2)), 2);
new_c1 = mod(sum(c1([1 2 5 7])), 2);
new_c2 = mod(sum(c2([1 2 3 6 8 9])), 2);
c1 = [new_c1 c1(1:n-1)];
c2 = [new_c2 c2(1:n-1)];
end
end

% 直接序列扩频函数
function [spread_signal] = spread_signal(signal, seq)
% 扩频序列的长度
len_seq = length(seq);
% 信号的长度
len_signal = length(signal);
% 扩频后的信号长度
len_spread_signal = len_seq * len_signal;
% 初始化扩频后的信号
spread_signal = zeros(1, len_spread_signal);
% 扩频
for i = 1:len_signal
spread_signal((i-1)*len_seq+1:i*len_seq) = signal(i) * seq;
end
end

% 直接序列解扩频函数
function [despread_signal] = despread_signal(spread_signal, seq)
% 扩频序列的长度
len_seq = length(seq);
% 扩频后的信号长度
len_spread_signal = length(spread_signal);
% 信号的长度
len_signal = len_spread_signal / len_seq;
% 初始化解扩频后的信号
despread_signal = zeros(1, len_signal);
% 解扩频
for i = 1:len_signal
despread_signal(i) = mod(sum(spread_signal((i-1)*len_seq+1:i*len_seq) .* seq), 2);
end
end

% 测试代码
n = 4;
c_init1 = 1;
c_init2 = 13;
seq_m = m_sequence(n, c_init1);
seq_gold = gold_sequence(n, c_init1, c_init2);
signal = [1 0 1 1 0 1 0 0];
spread_signal_m = spread_signal(signal, seq_m);
despread_signal_m = despread_signal(spread_signal_m, seq_m);
spread_signal_gold = spread_signal(signal, seq_gold);
despread_signal_gold = despread_signal(spread_signal_gold, seq_gold);
disp('原始信号：');
disp(signal);
disp('M序列扩频后的信号：');
disp(spread_signal_m);
disp('M序列解扩频后的信号：');
disp(despread_signal_m);
disp('Gold序列扩频后的信号：');
disp(spread_signal_gold);
disp('Gold序列解扩频后的信号：');
disp(despread_signal_gold);