On Tue, Jan 10, 2012 at 3:37 AM, Kouta NISHIDA
<address@hidden> wrote:
Tom Rondeau wrote:
On Mon, Jan 9, 2012 at 2:24 AM, Kouta NISHIDA <address@hiddenac.jp <mailto:address@hiddenkyutech.ac.jp>> wrote:
Hi all,
Now I use tunnel.py with USRP2.
I set bitrate when I run tunnel.py.
I cannot change the bitrate until I finish tunnel.py.
But, I want to change bitrate dynamically when I am running tunnel.py.
Does anyone know the ways to change bitrate dynamically?
regards,
kouta
Hi Kouta,
It's not set up to work that way right now, but you should be able to hack it to do what you want.
There are a couple of settings that affect the bitrate: the rate of the USRP and the number of samples per symbol (sps). In the current implementations of the PSK modulations, you can set a real number for the sps, so you should be able to change that to affect the bit rate. But remember, look for any place that is used since you'll have to also reset the taps for the filters on both the RX and TX sides.
You can also set the sample rate of the USRP as well to affect this.
Let us know how you do with this.
Tom
Thank you for your advice.
I will try setting the sample rate of the USRP to change bitrate dynamically.
I found the parameter that Actual Bitrate with pick_bitrate.py
Is the sample rate of the USRP Actual Bitrate ?
Would you tell me it if there are the file and parameter that I should pay attention to ?
regards,
kouta
Kouta,
If you're still using the pick_bitrate.py file, it sounds like you are on an older release (pre 3.5). In that case, you might have more trouble changing the bitrate (at least arbitrarily). But if you are using that version, you use that script to set the interpolation or decimation rates of the USRP as well as the number of samples per symbol based on a desired rate. So using it, if you want to set a new bit rate, you will receive new values for both of these parameters.
Tom