Progress Report on Software Spectrometer Development for GALFA
Date: Wed, 03 Sep 2003 17:43:40 -0400
From: Jeff Hagen
To: firstname.lastname@example.org, email@example.com,
Subject: GALFA software spectrometer
You asked me to give a short status report on the GALFA software
Paul Goldsmith gave me the Heiles signal processing document and I have
implemented those changes. This includes the ability to do fft overlaps
and Welch weighting.
Current performance status:
- 2.4GHz dual xenon motherboard
- 8192 spectral channels
- Welch weighting
- overlap factor of 3 (this is up from olap=2 that I reported to Paul
several weeks ago.)
- 40 MB/second (16 bit I and 16 bit Q). This refers to one polarization
at 10MHz or dual pol at 5MHz bandwidth.
- The digitizers run at 80 MHz and are digitally filtered and down
(from 30 MHz) in the graychip.
The next step is to do a practical test taking a standard on/off on the
telescope. I am going to finish the WAPP spectral line project first
as I can easily use the same software to produce the single dish FITS
data format. With a working WAPP spectral line mode, a software
spectrometer mode is an easy step.