Citation
Abstract
In this article we present an analysis of the impact of cross-polarization interference on the performance of wideband dual polarization communication systems with particular emphasis on the Surface Water and Ocean Topography (SWOT) X-band satellite communication system. SWOT transmits dual-polarized (right and left hand circular polarizations), offset-QPSK (OQPSK) modulated signals with a 310-Mbps information rate per polarization channel using the Earth Exploration Satellite Service (EESS) band: 8025–8400 Megahertz (MHz). Cross-polarization interference arises in several different ways including: (i) conversion of cross-polarization (cross-pol) to co-polarization (co-pol) interference due to reflections off the spacecraft structure (termed multipath); (ii) conversion of cross-pol to co-pol interference due to the cross-pol gains of the transmitting and receiving antennas and (iii) tropospheric depolarization. The ratio of co-pol power to the cross-pol converted “leakage” power is defined as cross-pol discrimination (XPD). The analysis presented in this article derives bit error rate (BER) formulas as a function of the number of reflected paths; the delay and XPD of each path, and the received signal-tonoise ratio. Furthermore, simple approximate BER formulas are derived that can be used to bound system performance based on parameter estimates obtained from an antenna model developed to predict SWOT performance.
Details
- Volume
- 42-213
- Published
- May 15, 2018
- Pages
- 1–23
- File Size
- 529.5 KB