ABSTRACT
The word synchronization refers to the process of making two or more events occur at the same time, or, by duality, at the same frequency. In a digital communication context, various levels of synchronization must be established before data decoding can take place, including carrier synchronization, symbol synchronization, and frame synchronization. In radio frequency communications, carrier synchronization refers to the process of generating a sinusoidal signal that closely tracks the phase and frequency of a received noisy carrier, transmitted by a possibly distant transmitter. Communication systems that have available, or somehow extract and make use of good carrier frequency and phase information are known as coherent systems, in contrast to incoherent systems that neglect the carrier phase Symbol synchronization is the process of deriving at the receiver timing signals that indicate where in time the transmitted symbols are located. The decision part of the receiver subsequently uses this information in order to decide what the symbols are.
