matlab으로 한 DSP 과제 신호의 노이즈 제거입니다.
- 최초 등록일
- 2009.05.05
- 최종 저작일
- 2008.10
- 5페이지/ 압축파일
- 가격 1,000원
소개글
matlab으로 구현하였습니다.
노이즈낀 신호를 받아서 신호를 원신호에 가깝게 복원하였습니다.
movingaveragefilter 사용하였습니다.
=========================================
과제 내용입니다.
0. Ftp the data file 'KTXSignal' from the ftp site "ftp://iclab.ac.kr/DSP" to your folder.
In Matlab command, load the data file "KTXSignal'. Check the data variable. The sampling rate of the sisgnal is 100/sec.
>> load KTXSignal
>> load KTXSignalWithNoise
1. Plot 'KTXSignal' along the actual time axis 't'.
>> plot(t,signal)
2. Plot 'KTXSignalWithNoise' along the actual time axis 't'.
>> plot(t,KTXSignalWithNoise)
3. We want to remove the noise from 'SigWithNoise' by an average filter . We denote the filtered signal as . For an example, when L=10, in Matlab
>>L=10;
>>h=ones(1,L)/L;
>>y=conv(h,KTXSignalWithNoise);
1) Check for the length of y[n]. Let p be the length of y[n]. Determine the length of y[n] in terms of L and M=length(SigWithNoise).
2) When L=10,
● plot y[n] in discrete index n and also y in time scale.
>> plot(y);
>> plot(t,y); % length of t should be adjusted to the length of y.
● plot the frequency response of 'h[n]'. In Matlab, you can use 'freqz'
>> [Hf,theta]=freqz(h,1);
>> plot(theta,abs(H)); % for ploting magnitude of 'h[n]'.
>> plot(theta,angle(H)); % for ploting angle of 'h[n]'.
3) Repeat 2) for L=2,5,10,15,20. Observe the following as L changes.
● Degree of noise removing and smoothing y[n].
● The transient time.
● Determine the optimal L.
● Shape of abs(H(theta)). (sharpness of cutoff frequency, magnitude of side lobes)
=> You can overlay 'abs(H(theta))' for L=2,10,20. Then you can recognize the shape change of abs(H(theta)).
컴파일 실행환경
matlab
압축파일 내 파일목록
matlap(hw2).hwp
KTXSignal.mat
KTXSignalwithnoise.mat
참고 자료
없음