Citation

Abstract

Previous articles have hypothesized that doppler rms phase jitter (noise) is proportional to integrated signal path electron density. In this article, observations of Viking differenced S-band/X-band (S-X) range are shown to correlate strongly with Viking doppler noise. A ratio of proportionality between downlink S-band plasma-induced range error and two-way doppler noise is calculated as: A new parameter (similar to the parameter € which defines the ratio of “local” electron density fluctuations to mean electron density) is defined as a function of observed data sample interval (tT): where the time-scale of the observations is 157. This parameter is interpreted to yield the ratio of “net” observed phase (or electron density) fluctuations to integrated electron density (in rms meters/meter). Using this parameter and the “thin phase-changing screen”’ approximation, a value for the scale size L is calculated: To be consistent with Doppler noise observations, it is seen necessary for L to be proportional to closest approach distance a, and a strong function of the observed data sample interval, and hence the time-scale of the observations.

Details

Volume
42-38
Published
April 15, 1977
Pages
172–183
File Size
711.3 KB