Method and apparatus for coherent demodulation in communication system employing a potentially gated pilot signal

The invention claims a which is used for using the selection signal control system and method for demodulation method and system of novel and improvement pilot frequency tracking operation. The invention claims a concurrent two operating method and device for frequency tracking hanging ring, a first frequency tracking ring according to a first speed supposition tracking high frequency signal; the first speed is provided with during the frame is continuous for pilot signal of; aThe second frequency tracking ring according to the second speed with the tracking the communication signal the frequency; the second speed is provided with exists for pilot signal of the rotator bracket portion of durations; And multiplexers, wherein according to the first speed supposition, providing the central frequency estimate, and according to the second speed supposition, providing the central frequency estimate.