Thanks Eric.
So the packet encoder samples /symbol does not affect the bit rate but just needs to match the dpsk samples/ symbol rate?
From: Eric Blossom <address@hidden>
To: David Barton <address@hidden>
Cc: address@hidden
Sent: Wed, May 12, 2010 2:02:42 PM
Subject: Re: [Discuss-gnuradio] Simple digital data transmitter
On Wed, May 12, 2010 at 09:06:13AM -0700, David Barton wrote:
> Hi,
>
> I have set up the following simple digital data transmitter:
>
>
> File source -à throttle -à packet encoder --- > DBPSK modulator -à USRP2
> File size sample rate
samples/sym - 2 samples/sym – 2 Inter rate 32
> -variable 3.125M bits/sym - 1 excess BW – 0.35 Freq 400M
> access code – n/a grey code - yes Gain
0
> pad for USRP – yes
> payload len – 0
>
>
> What is the transmit (over the air) data rate of this line up ?
>
> Please explain how the rate is derived.
>
> Thanks,
> Dave
Remove the "throttle", it's not needed.
Your baseband sample
rate is 100M/32 -> 3.125MS/s
You're using 2 samples/symbol, thus your symbol rate is
3.125MS/s / 2 -> 1.5625Msymbols/s
And since you're using DBPSK, you're getting 1 bit/symbol, thus your
raw over-the-air bit rate is 1.5625Mbit/s
Eric