next up previous
Next: Data Rates Up: E-ALFA Hardware Previous: WAPP notes


The current WAPP as the initial spectrometer

As we understand it, the current plans will have available only the WAPP for E-ALFA at the end of 2004. We hope that longer range plans will get us the additional capacity we need to achieve our science goals as outlined in the ideal backend summary, but here is the minimum that we can expect to have on January 1, 2005.

See Jeff Hagen's notes page for more information on the (Wide Band Pulsar Processor) WAPP in general, and Jeff's handout which also gives more details. Here, we summarize the most relevant ones with a few astronomer-friendly units added for convenience (for those who might not think naturally in kHz yet).

For each of the 7 beams, the maximum capability is given below. The last line contains what the ideal backend would deliver for comparison.

Bandwidth # pols # of spectral points d(freq) d(vel @ 1.4 GHz) sampling level
100 MHz 1   2048 48.8 kHz 10.6 km/s 9
    " 1   8192 12.2 kHz   2.6 km/s 3
    " 2   4096 24.4 kHz   5.3 km/s 3
                       
  50 MHz 1   4096 12.2 kHz   2.6 km/s 9
     " 1 16384   3.0 kHz   0.65 km/s 3
     " 2   2048 24.4 kHz   5.3 km/s 9
     " 2   8192   6.1 kHz   1.33 km/s 3
                       
Ideal 200 MHz 2   8192 24.4 kHz   5.3 km/s >= 8 bit (12?)

Further considerations:



next up previous
Next: Data Rates Up: E-ALFA Hardware Previous: WAPP notes


This page created and maintained by Martha Haynes.

Last modified: Tue Oct 7 17:26:47 EDT 2003