Multipath in Space Station Freedom S-band single access forward link

The Space Station Freedom (SSF) S-band multipath effect varies dynamically during an orbital pass because of the relative SSF structure movements to the antenna pointing direction. The received signal envelope fluctuation can cause serious degradation on the communication link. In the paper, dynamic geometrical information about the SSF structures and the antenna pointing direction for any SSF orbital passes is generated. Then, the received signal envelope fluctuation including the multipath effects is computed by combining an extended uniform geometrical theory of diffraction with the dynamic SSF geometrical information. Finally, the bit error rate degradation due to the multipath is analyzed, and compared with that of the typical Rician or Rayleigh fading multipath channel.<
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