%用于求BPSK調(diào)制信號的循環(huán)譜?
tic
clc
clear?;
clear?all;
%%%%%%%%%%%%%%%仿真參數(shù)設(shè)置%%%%%%%%%%%%%%%%%
fd=1;??????????????????????????????????????%數(shù)據(jù)速率為1k
Ts=1/fd;???????????????????????????????????%碼元間隔Ts=0.001s
delt=2^7;??????????????????????????????????%時間段
fc=2;??????????????????????????????????????%載波頻率2k
fs=8;??????????????????????????????????????%采樣頻率8k
dt=1/fs;???????????????????????????????????%采樣時間間隔Ts=1/fs
num=fd*delt;???????????????????????????????%碼元個數(shù)
t=[0:dt:delt-dt];??????????????????????????%時間向量
%%%%%%%%%%%%%%產(chǎn)生數(shù)據(jù)%%%%%%%%%%%%%%%%%%%%%%?????
data=sign（randn（1num））;
%%%%%%通過基帶成型濾波器后的信號（矩形成型）%%%%%%%%%%%%
?for?rr=1:num
????I（（rr-1）*fs+1:rr*fs）=data（rr）;
end
%%%%%%%最終BPSK調(diào)制信號%%%%%%%%%%%%%%%%%%%%%
xx=I.*cos（1*2*pi*fc.*t）;
x=awgn（xx-3）;?????????????????????????????%信號加入高斯白噪