On Tue, 19 Feb 2008 13:07:11 -0800 (PST), Rune Allnor
<[email protected]> wrote:

>On 19 Feb, 21:52, dbd <d...@ieee.org> wrote:
>> On Feb 19, 9:29 am, Rune Allnor <all...@tele.ntnu.no> wrote:
>>
>>
>>
>>
>>
>> > On 19 Feb, 18:10, dbd <d...@ieee.org> wrote:
>>
>> > > On Feb 19, 4:15 am, Rune Allnor <all...@tele.ntnu.no> wrote:
>>
>> > > > On 7 Feb, 17:43, "Pavel.Schu...@gmail.com" <Pavel.Schu...@gmail.com>
>> > > > wrote:
>>
>> > > > > *What is the impulse response
>> > > > > of fiter matched for example with rectangular transmit filter *or
>> > > > > raised cosine filter in that case?
>> > > > Window functions in a matched filter? That's a new one.
>> > > > How does that work?
>> > > > Rune
>>
>> > > If the signal was generated by windowing, as all finite signals are,
>> > > don't you try to match the window?
>>
>> > Not explicitly. The way I know the matched filter, you
>> > try and match the impulse response. How the impulse is
>> > found is a separate issue. If a non-rectangular window
>> > function was used somewhere it would be part of the
>> > impulse response already and not need explicit handling.
>>
>> > Rune
>>
>> Rune
>>
>> *You are the only one to suggest any explicit handling of windowing.
>
>You are right. I didn't understand (and still don't) why and
>how the terms 'rectangular' or 'raised cosine' appear in
>a discussion about matched filters. Are these impulse repsonses
>or transfer functions?
>
>Rune

I think you guys are on the wrong channel.

He's talking about a communication system where the "matched filter"
is the pulse shaping filter. Root Raised Cosine is a very common
matched filter that is applied to both the transmit and recieve pulses
to get a Raised Cosine frequency response.

The "rectangular" reference means unfiltered NRZ pulses, i.e.,
rectangular symbols.

Hope that helps...



Eric Jacobsen
Minister of Algorithms
Abineau Communications
http://www.ericjacobsen.org