Citation

Abstract

The experiment to detect gravitational waves in ultraprecise Doppler data requires a total system (DSN Tracking System, spacecraft transponder, and media) fractional frequency fluctuation of approximately 1X 10-!5 for averaging times greater than 1000 seconds. At such levels, solar wind density fluctuation looms as a very difficult error source. This article presents a detailed examination of solar wind electron (columnar) density fluctuation as it applies to the experiment to detect gravitational waves in ultraprecise doppler data. Expected two-way S-band fractional frequency fluctuation (due to solar wind density fluctuation) at a 1000-second averaging time is considered to be approximately 3 X 10-13, while the optimum two-way X-band (X-band uplink and downlink) performance is predicted to be (also at a 1000-second averaging time) approximately 1 X 10-14. The article concludes that both two-way S-band and X-band will be required (simultaneously) so that the predicted two-way X-band performance (~10-!4} can be improved to a (defined) media goal of 3 X 107!° via two-way dual frequency calibration of solar wind induced density fluctuation.

Details

Volume
42-44
Published
April 15, 1978
Pages
189–196
File Size
513.6 KB