rcosfir11.m

来自「对数字信号进行分析」· M 代码 · 共 41 行

function [frame2]=rcosfir11(frame1,tb,fs)
runum1=length(frame1);
frame3=zeros(1,runum1*100);
for i=0:1:runum1-1
    frame3(1,i*100+1:i*100+100)=frame1(1,i+1);
end
nsamp = 2; % Oversampling rate
rolloff=0.05;
% Modulator
% M = 16;
% Filter Definition
% Define filter-related parameters.
filtorder = 40; % Filter order
delay = filtorder/(nsamp*2); % Group delay (# of input samples)
% rolloff = 0.25; % Rolloff factor of filter

% Create a square root raised cosine filter.
rrcfilter = rcosine(1,nsamp,'fir/sqrt',rolloff,delay);

% Transmitted Signal
% Upsample and apply square root raised cosine filter.
frame2 = rcosflt(frame1,1,nsamp,'filter',rrcfilter);

bb=rcosfir(0.05,[-100,100],2,1/(8e-6),'sqrt') ;
frame2=filter(bb,1,frame3);

tb=tb/100;
% fs=fs*10;
runum1=length(frame2);
t1=tb:tb:tb*(runum1);
figure
plot(t1,frame2)
f1=1:fs/runum1:fs;
X=abs(fft(frame2));
X=10*log10(X);
figure
plot(f1,X)
title('未随机化频谱图')
xlabel('频率Hz')
ylabel('幅度(dB)')