TWSTT Non-Reciprocity for the USNO - NPL I-706 Link

The figure below shows the model time non-reciprocity in the USNO - NPL Ku-band TWSTT link. The simple GPS-type model is used to compute a path delay for each path (four total) between the ground and the satelite. The local solar time for each station is accounted for as are the appropriate up/down frequencies for each path. All four model ionospheric path delays were combined to produce the model non-reciprocity for each hour of the day. A value of the solar flux was chosen as 230. The example was computed for 1 May 2001.

The model estimate of the ionospheric path delay non-reciprocities at an hourly rate. The hours have been converted to UTC decimal of a day. The plot shows two full days (-1.0 to +1.0).

This page is http://tycho.usno.navy.mil/twsttcal.html
(17 June 2001)

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