Reverse power control
  1. Open loop power control
  2. Closed loop power control
  • Inner loop power control:  800 Hz
  • Outer loop power control

Forward power control

  • Message transmission mode:
  • threshold transmission
  • periodic transmission
  • Closed loop power control 

 

Reverse open loop power control means that based on the detected signals from a base station, a mobile station makes a preliminary judgement of the attenuation of an air path and specifies what transmitting power should be used to transmit signals. 
If the mobile station receives strong signals, it shows there is weak air attenuation and the mobile station transmits signals at a smaller power. If the mobile station receives weak signals, it shows there exists strong air attenuation and the mobile station will transmit signals at a greater power. Reverse closed loop power control means that after receiving a signal from a mobile station , a base station will judge its strength. 
If the signal is higher than the threshold needed by the base station, the base station sends an instruction that the mobile station should decrease the transmitting power. 
If the signal is lower than the threshold needed by the base station, the base station sends an instruction that the mobile station should increase its transmitting power. Forward power control is similar to reverse power control, but the former controls the signals a base station transmits to various users.