EVLA data rates 

JMB 2009-12-20

offical observing data rate limit : 25 MB/sec

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current test obs :

int. time = 1 sec
1028 spectral points, 1 polarization per subband
complex word
8 subbands..
12 antennas = 66 bslns


1024 x 2 x 4bytes x 8 subbands = 65.5 KB per baseline per integration

65.5 KB x 66 bslns = 4.3 MB per integration 

4.3 MB x 3600sec/hr = 15.5GB/hour 

Am observing about 16GB/hour

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Predicts for OSRO :

Spectral line mode 

Provide one tunable sub-band, dual polarization, 256 spectral chans

256 x 2 x 4 bytes x 2 polar x 1 sub-band = 4.096 KB per baseline per integration

4.096 KB x 351 baselines = 1.42 MB per integration

1.42 MB x 3600 sec/hour = 5.1 GB/hour


Continuuum mode

2 sub-bands

64 spectral points, 4 polarizations per subband

64 x 2 x 4bytes x 4 polar x 2 sub-bands = 4.096 KB per integration per baseline

4.096 KB x 351 baselines = 1.42 MB per integration

1.42 MB x 3600 sec/hour = 5.1 GB/hour


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Predicts for RSRO :


Provide 16 sub-bands, full polarization, 64 spectral channels

64 x 2 x 4bytes x 4 polar x 1 sub-band = 2.048 KB per obs per baseline per sub-band

2.048 KB x 351 baseline = 0.719 MB per integration per sub-band

0.719 MB x 3600 sec/hour = 2.59 GB/hour per sub-band

up to 16 sub-bands --

max RSRO -> 41.4 GB/hour