[evlatests] MUOS RFI

[Rick Perley]

     Tracy wrote that the MUOS spectra cover 64 MHz, from 320 -- 384 MHz.

     That's quite a bit more than we actually see.

     I took some high-resolution (time and frequency) data last week to 
check P-band sensitivity.  There was a good mix of long (A-config) and 
short (D-config) baselines.  The MUOS spectral are blindingly obvious on 
all the short spacings.

     The main RFI are in four blocks, each covering 5.00 MHz:

     360.5 -- 364.5
     365.5 -- 369.5
     370.5 -- 364.5
     375.5 -- 379.5

     These are broad band signals with no spectral features.  They 
disappear quite well in the long spacings.

     But in addition, there are six strong but narrow (effectively CW) 
signals at:

     353.25
     355.81
     356.81
     358.56
     359.31
     359.81

     The spectral intensity is much higher in these, but since they are 
so narrow, there is little power.

     I hadn't seen these six CW signals before.  I'm guessing there's 
part of the 'MUOS" spectrum.

     We'd better hope the part of the spectrum noted by Tracy is 
belonging to MUOS, but within which we see no RFI, stay that way. The 
320 -- 360 MHz spectrum is the most sensitive part of the band.