Match Filter and Sampling problem
조회 수: 9 (최근 30일)
이전 댓글 표시
clc;
clear all;
close all;
tp=2.2676*10^-3;
Ts=22.6757*10^-6;
fc=4000;
Tc=(1/fc);
fs=44100;
n=0:Ts:1000;
fp=(1/tp);
w=2*pi*fp;
p=sin(w*n*Ts);
p(find(p<0))=0;
figure(1)
subplot(3,1,1);
plot(n,p);
data = randi([0,1],1,1000);
a=[];
for k=1:2:1000
if data(k)==0 && data(k+1)==0
a=[a 1];
elseif data(k)==0 && data(k+1)==1
a=[a i];
elseif data(k)==1 && data(k+1)==0
a=[a -1];
elseif data(k)==1 && data(k+1)==1
a=[a -i];
end
end
figure(2)
subplot(3,1,2);
y_s=conv(a,p);
Trm=min(numel(n),numel(y_s))
n=n(1:Trm);
y_s=y_s(1:Trm);
plot (n,real(y_s), '-',n,imag(y_s), '--');
%% modulation of 2 signals
figure(3)
subplot(3,1,3);
in_phase_carrier=cos(2*pi*fc*n*Ts);
q_phase_carrier=sin(2*pi*fc*n*Ts);
y_m=real(y_s).*in_phase_carrier+imag(y_s).*q_phase_carrier;
plot (n,real(y_m), '-');
subplot(3,2,3);
plot(n,imag(y_m), '--');
pav=sum(y_m.^2)/length(y_m);
et=sum(y_m.^2)/fs;
snrdb=20;
snrlin=10.^(snrdb./10);
eb=sum(y_m.^2)/length(y_m);
u=0.00022676;
g=5/60;
n1=(u-n);
in_phase_carrier_rec=cos(2*pi*fc*n1*Ts);
q_phase_carrier_rec=sin(2*pi*fc*n1*Ts);
y_mn1=(real(y_s).*in_phase_carrier_rec)+(imag(y_s).*q_phase_carrier_rec);
figure(4)
subplot(4,1,4);
r = (sqrt((1-g)^2))*y_m+y_mn1*g;
plot(n,r);
snrdb=20;
snrlin=10.^(snrdb/10);
n0 = eb/snrlin;
sigma=(n0.*fs)/2;
noise = sqrt(sigma).*randn(1,length(y_m));
recieved=noise+r;
%% demodulation of signal
subplot(4,2,4);
r_dm_in=real(recieved).*in_phase_carrier;
plot(n,r_dm_in,'-');
r_dm_out=imag(recieved).*q_phase_carrier;
plot(n,r_dm_out,'--');
Hello I am trying to demodulate using match filter and sampling it wwith 44100Hz. can anyone help with match filter and sampling of this code.
댓글 수: 1
Subhadeep Koley
2019년 11월 5일
Your code is running without an error. Can you elaborate what problem exactly you are facing? What is you expecting as the output?
답변 (0개)
참고 항목
카테고리
Help Center 및 File Exchange에서 Modulation에 대해 자세히 알아보기
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!