primary signal face

例句：

1. 1. The primary signal face ofthe satellite is crucial for communication.
   卫星的初级信号面对于通信至关重要。
2. 2. The primarysignal face of the satellite was designed tobe easily readable by humans.
   卫星的初级信号面被设计成人类易于阅读。
3. 3. The primary signal face of the satelliteis used to transmit signals between the satelliteand ground stations.
   卫星的初级信号面用于在卫星和地面站之间传输信号。