To: File

From: Jon Hagen

Date: April 10, 2003, 4-16-03

Subject: Alfa backend requirements - summarized by Avinash Deshpande in a conversation following an Alfa meeting today:

BW Channels Input Output Dump Misc

levels levels time

1. P-Alfa 300MHz 1k 8 bits 4bits max 64usec output after long-term

300kHz res. min (flexible) mean removed in SW

2. E-Alfa 200MHz min 25kHz res 8bit min 16 bits min 1sec flexible blanking

(extragalactic) (8000ch) 12 desired @1 sec dumps .1 (or even 1ms) in hardware

for rfi excision

3. G-alfa HI 1415-1425 1kHz res min 10 desired 10 bits 1sec blanking not

(galacatic HI: =10k Channels (few ok if little rfi) needed*

(20k desired)

4. G-alfa One 6MHz band 0.5 kHz 8 bits (min) 10bits <1 sec. blanking not

spec. line +eleven (1kHz min needed*

3MHz bands ~ 40k channels)

(all fixed)

5. G- alfa 300MHz 1k 8 bits (min) 16 bits 0.1 sec blanking not needed*

continuum

(like P-Alfa)

but w/full

Stokes

*rfi excised in software