## Matched filter

### vsee (view profile)

on 1 Apr 2011
Latest activity Commented on by Honglei Chen

### Honglei Chen (view profile)

on 12 Jan 2017

How can I write a mtached filter in Matlab? I have the filter design and signal processing tool boxes.

### Honglei Chen (view profile)

on 1 Apr 2011

If you have a signal, x, then the matched filter's coefficients is given by time reverse of x, i.e., x(end:-1:1). If your signal is complex, you also need to to use complex conjugate. You can then use it just as an FIR filter. For example,

```>> x = ones(10,1);
>> b = x(end:-1:1);
>> y = filter(b,1,x);
```

Nuzat Alam

### Nuzat Alam (view profile)

on 3 Apr 2013

Hii i was wondering what is the impulse response of matched filter here?I think it is related to b. Do you think if i want to select a specific sample number for b, i also need to change the length of input signal x?

### Mustahsan Ali Khan Khanzada Rajput (view profile)

on 12 Jan 2017

How to apply matched filter if the signal is complex?

Honglei Chen

### Honglei Chen (view profile)

on 12 Jan 2017

It's the same, use the filter function. The only difference is when you come up with the filtering coefficient, you need to add a conjugate, like

```b = conj(x(end:-1:1))
```

HTH

### Andrew Newell (view profile)

on 1 Apr 2011

Check out MATLAB Simulations for Radar Systems Design from the File Exchange.

on 15 Apr 2011

To elaborate on Honglei's answer. If the signal you are trying to design a matched filter for, is x, then --

```>> b = x(end-1:1);
>> y = filter(b,1,x);
```

mmm ssss

### mmm ssss (view profile)

on 9 Jan 2012

how can implement the same filter on image ?

how i should represent x.

### Mathuranathan Viswanathan (view profile)

on 13 Apr 2013

Hi You can try the model given here

Square Root raised Cosine - Matched filter implementation http://www.gaussianwaves.com/2011/04/square-root-raised-cosine-filter-matchedsplit-filter-implementation-2/

Regards Mathuranathan

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