Re: AGC and PGC

Hi Pierre,

As far as I understand the TVRx board has two AGC stages: An RF and IF
AGC.
Look in this file: (gnuradio-3.1.1/gr-usrp/src/db_tv_rx.py) to see how
GnuRadio models the gain characteristics in the data sheet and
subsequently
sets the appropriate registers.

Here you will note that the PGA is also set, the PGA though does not
reside
on the daughterboard, but is part of the AD9862.

I’m sure the list will correct me, if i’m mistaken.

I would be interested to see how your work in this area progresses and I
would appreciate it if you would keep me updated.
perhaps we could collaborate, i too am interested to investigate USRP
and
TVRx performance in various characteristics.

I’m working towards eventually building a PCL radar.

regards,

Aadil

Date: Thu, 13 Dec 2007 09:40:27 +0100
From: “JALLON Pierre 201932” [email protected]
Subject: [Discuss-gnuradio] AGC and PGC
To: [email protected]
Message-ID:
[email protected]
Content-Type: text/plain; charset=“us-ascii”

Dear all,

I would like to compare two signals in two distinct bands of frequencies
(energy in particular) with the TVRX module.

Is there an AGC in the USRP/TVRX module ? If yes, how can I get its
value ?
How the programmable gain (set with the command set_gain of the sub
device) impacts on the energy signal ?

Thanks for your answer !

Pierre Jallon