【MATLAB】帶限基帶傳輸系統的模擬
阿新 • • 發佈:2019-02-12
用Matlab通訊工具箱提供的rcosine函式作出一組滾升餘弦濾波器的衝激響應,滾降係數為0,0.5,0.75和1,並通過FFT求出其幅頻特性。碼元時隙為1ms,在一個碼元時隙內取樣10次,濾波器延時為5個碼元時隙。 程式如下:
如圖:clc; Fd = 1e3; Fs = Fd * 10; delay = 5; for r = [0,0.5,0.75,1] num = rcosine(Fd,Fs,'fir/normal',r,delay); t = 0 : 1 / Fs : 1 / Fs * (length(num) - 1); figure(1); plot(t,num); axis([0 0.01 -0.2 1.1]) hold on; Hw = abs(fft(num,1000)); f = (1 : Fs / 1000 : Fs) - 1; figure(2); plot(f,Hw); axis([0 1500 0 12]); hold on; end