Synchronization of Coherent Detectors

The estimation of carrier frequency and subcarrier epoch in a coded-"noise" communication system is discussed. These are the parameters which constitute synchronization of the system. The estimation process is resolved into a sequence of detections, and the distribution of the time necessary to achieve an estimation to within a preset accuracy is given. Various electronic detection methods are considered; in particular, an interesting application of sequential detection is described. This paper treats only the synchronization mode of the receiver. No message information is transmitted until synchronization has been achieved, at which point the receiver enters the communication mode.