Today digital data transmission plays a leading role for satellite systems.  However, digital data transmission is possible with errors at demodulation, which cause distortion of transmitting information. Errors of digital data transmission are due to three causes. First cause is a low level of signal to noise ratio. Second cause is Doppler Effect. Third cause is symbol-to-symbol interference conditional multipath propagation. Space diversity reception is effective method of bit error resistance.

Doppler Effect is the most significant for bit error probability at satellite communication. Because satellite move very fast in cosmic space. This article show effective of space diversity reception for decrease of bit error probability, which caused by Doppler Effect.