PHYSICAL LAYER HAND-OFF AND DIVERSITY COMBINING IN NON-GEOSTATIONARY SATELLITE CONSTELLATION

摘要

At least two antennas are used for make-before-break communications over non-geostationary satellites. An SHDC device provides physical layer seamless hand-off and obtain diversity signal-to-noise ratio (SNR) gain. When additional antennas are available for standby or other reasons, it may be beneficial for a number of satellite antennas to collectively utilize additional SHDC devices to achieve higher diversity SNR gains under normal operational considerations. The asymptotic SNR gains are those obtained when receiver antenna noise dominates transponder and sky noises. According to exemplary embodiment of the present invention, N satellite antennas may collectively utilize N-1 SHDC devices. For example, 3 satellite antennas may collectively utilize 2 SHDC devices.