Analysis of GPS patch antenna covered by re-entry plasma sheath

A plasma sheath enveloping a reentry vehicle would affect on-board antennas performances greatly, especially the navigation antennas. This paper studies the effects of plasma sheath on a GPS microstrip patch antenna during a typical reentry phase. Utilizing the algorithm of time-domain finite integration, the radiation and admittance characteristics of the GPS antenna coated by plasma sheath are obtained. The changes in antenna characteristics are analyzed and the process of a reentry blackout is also reproduced from the respect of the antenna performance degradations.