Equalization in satelleite channel

> > >>
> > You can sometimes get a bit better ISI with a bit of equalisation as the
> > channel filter often puts a bit of  slope at the band edges and this isn't
> > always equalised in the uplink.
> >
> > Best of Luck - Mike
> >
> >
>
> By the way IF you do need an equalizer it probably doesn't have to be very
> long (4-5 symbols) so the answer may be better safe than sorry since it
> won't cost you much.
>
> -Clark

There are many things in the system that could put some slope in the
system, for example  the transmission lines feeding the antennas may
have some mis-match and can cause ripple in the passband.  Adaptive EQ
will improve that.  You may not NEED to have adaptive EQ to close the
link,   but adaptive EQ in the receiver will help to keep the
implementation losses in the overall system at a minimum.

Mark

On 21 Sep 2006 17:04:32 -0700, "Mark" <makolber@yahoo.com> wrote:

>> > You can sometimes get a bit better ISI with a bit of equalisation as the
>> > channel filter often puts a bit of  slope at the band edges and this isn't
>> > always equalised in the uplink.
>> >
>> > Best of Luck - Mike
>> >
>> >
>>
>> By the way IF you do need an equalizer it probably doesn't have to be very
>> long (4-5 symbols) so the answer may be better safe than sorry since it
>> won't cost you much.
>>
>> -Clark
>
>There are many things in the system that could put some slope in the
>system, for example  the transmission lines feeding the antennas may
>have some mis-match and can cause ripple in the passband.  Adaptive EQ
>will improve that.  You may not NEED to have adaptive EQ to close the
>link,   but adaptive EQ in the receiver will help to keep the
>implementation losses in the overall system at a minimum.
>
>Mark

Yeah, that's generally right by my understanding, i.e., the only
reason to use an EQ in a satellite link is to correct for tilt or
other non-flat signal pass behavior in the transponder.  This usually
only comes into play when trying to use higher-order modulations like
16-QAM or higher.

There's no multipath to speak of in satellite systems as there are no
significant reflectors along the signal path and the antennas are
highly directive.

Eric Jacobsen
Minister of Algorithms, Intel Corp.
My opinions may not be Intel's opinions.
http://www.ericjacobsen.org