|
On 07/02/2015 05:51 PM, Varun Nambiar
wrote:
Hey Marcus,
I'm getting the FFT over a 1 MHz bandwidth and I'm computing
the average signal strength over a 125 kHz region of that 1
MHz region by integrating all the samples and dividing by the
number of samples. I'm hoping to get an RSSI estimate over the
input bandwidth. My issue is that I can't write to the file at
2 samples/sec. When I execute the code in the attached GRC, at
the moment of execution I get a 32 KB file with 0s and it
doesn't output any samples to the file. When the throttle
block is removed, the processor on the E310 writes to the file
at the clock speed which leads to incredibly large files. Is
there a way to cut it down to 2 samples/sec? Also the Avg
Mag^2 block is there to probe for signals of strength greater
than -70 dB.
Thanks,
Varun
Why not:
signal-source--->filter---->complex-to-mag^2---->single-pole-iir-filter--->keep-one-in-N----->file-sink
Adjust your post-detection filtering and keep-one-in-N to be
consistent with your desired logging rate.
On 07/02/2015 03:26 PM, Varun
Nambiar wrote:
Hi all,
Here's the GRC file. Any help would be appreciated!
Thank you,
Varun
Could you clarify whether you want RSSI estimates over the
whole input bandwidth, or for each discrete frequency bin?
This graph shows confusion in a number of areas, so, what is
it you're trying to do?
________________________________________
From: Philip Balister <address@hidden>
Sent: Thursday, July 2, 2015 1:35 PM
To: Varun Nambiar; GNURadio Discussion List
Subject: Re: [Discuss-gnuradio] Writing RSSI Values to a File Twice/Sec
On 07/02/2015 11:25 AM, Varun Nambiar wrote:
Hi Philip,
At the moment of execution a file size of 32KB with just 0s is written to my file and then it doesn't add anymore values after that. I am on release-2 and I've attached my GRC file.
I dropped the throttle block and saw the output file get larger. Resend
the flowgraph to the list and maybe someone else has some ideas how to
make it better.
Philip
Thank you,
Varun
________________________________________
From: Philip Balister <address@hidden>
Sent: Thursday, July 2, 2015 11:18 AM
To: Varun Nambiar; address@hidden
Subject: Re: [Discuss-gnuradio] Writing RSSI Values to a File Twice/Sec
On 07/02/2015 11:07 AM, Varun Nambiar wrote:
Hi all,
I'm new to GNURadio and I'm trying to use a USRP E310 to capture GSM signals from a cellphone and store the RSSI values in a text file. If you take a look at my flow graph I've managed to capture the average strength across the 200kHz GSM band and I'm trying to filter out the unwanted signals using the Probe Avg Mag^2 block.
I'm having trouble writing to the file sink at a constant 2 samp/sec. Could you please give me advice on how I should fix my flow graph?
What kind of trouble? Can you also post the grc file so I can try it
locally.
Also, which file system image are you using? The one from the card that
came with the unit, or release-2?
Philip
Thank you,
Varun
_______________________________________________
Discuss-gnuradio mailing list
address@hidden
https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.gnu.org_mailman_listinfo_discuss-2Dgnuradio&d=AwIC-g&c=1QsCMERiq7JOmEnKpsSyjg&r=oML8w7v4Y02f11gsS3bWKQ&m=hC1yMZO9YJC94wCgIZWYH9bbke_ocPJKoWRVfAMsuMo&s=8BPBpMr_86l6B-6kzl20V_C-fjCtQ-eOYPqCNrrvwCE&e=
_______________________________________________
Discuss-gnuradio mailing list
address@hidden
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
|