[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] Periodic averaging

From: Prachi Parihar
Subject: Re: [Discuss-gnuradio] Periodic averaging
Date: Mon, 8 Aug 2011 16:54:29 -0400

Thanks for your response Marcus. I have been working with this block, but unfortunately, I do not want to iir filter the power spectrum. I want each spectrum to be weighed equally. I'd like to compute the arithmetic mean for all the power spectra within a minute (I believe there are 4000 per second) so that means I want to average 240,000 spectra and return a single power spectrum (which is the average) to be displayed. 

As for the "keep one in N" file dump, I considered that when I came across moving_average_ff but that calculates the average every time it receives a new spectrum which is very wasteful in my case, since it's computing the average 240,000 times more than I need to.

On Mon, Aug 8, 2011 at 12:45 PM, Marcus D. Leech <address@hidden> wrote:
On 08/08/2011 12:31 PM, Prachi Parihar wrote:
Hi everyone, 

I'm new to gnuradio and I was wondering if someone could point me in the right direction. I'm using a usrp to read signals in the frequency domain. I've been able to do this successfully using uhd_fft.py which uses fft_sink_c() to display the signal. 

What I want to do instead of displaying the signal continuously is to display the average of the power spectrum of the signal every minute using all the samples collected in one minute. I can't find a block that simply takes the (boxcar) average of many spectra once every minute. 

If I can't find a block to do this, I will attempt to write one myself. If I need to, is there a strong need to write this block in C++ or could I write it in python? 

Thanks in advance for your help, 

Discuss-gnuradio mailing list
There's a logPowerFFT hier block in GRC that allows you to set the frame rate and "alpha" value, and it produces a FLOAT vector that's
  the length of the FFT.

You can then further IIR filter those vectors, and then do a "keep one in N" to make them dump to a file once per minute.

Discuss-gnuradio mailing list

reply via email to

[Prev in Thread] Current Thread [Next in Thread]