[evla-sw-discuss] EVLA WIDAR: Delay Model - format and content

[Brent Carlson]

Comments:

>3.  Timestamps.  We work internaly in a double precision MJD and fraction
>system (LSB is about one microsecond).  Converting that to ISO 8601 form 
>is easy of course, but I rather suspect that you also will be working in 
>some similar system internally, and it might save a few a little bother at 
>both ends just to send that.
>  
>
Having the timestamp in the form of seconds and milliseconds since some 
system-defined epoch is the most convenient for the correlator.

>4.  Delays.  Who organizes the delay center?  Do I send numbers which might
>be negative, or should I add something to them to make them always positive?
>If so, what?
>  
>
I think it is most unambiguous if the pure delay, without any offset, is 
sent to the correlator.  If the s/w engs follow the 
discussion/implementation on delay tracking in the Programmer's Guide to 
the correlator, then any offsets required will be incorporated in CMIB s/w.

Brent

-- 
Brent R. Carlson
Brent.Carlson at nrc-cnrc.gc.ca
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