UNIQUE WORD DETECTION METHOD AND ITS ERROR RATE PERFORMANCE.

In digital satellite communications, the Unique Word (UW) having a unique code pattern is often used for frame synchronization. Reliable detection of the UW is very important to achieve stable frame synchronization. This paper proposes a UW detection method capable of providing lower UM error rates even with a low carrier-to-noise ratio. The UW error rate (UWER) performance of the proposed method has been examined for the case where hard-decision or soft-decision is applied to the UW bits which are transmitted in the form of binary phase-shift keying and coherently demodulated. The UW detection processes are described for both the proposed and the conventional methods, and computed or simulated results of the UWERs are presented on the assumption of typical UW pattern. Comparison is made between the UWER performances of the proposed method and of the conventional method. It is shown that the proposed method incorporated with soft-decision can provide excellent UW detection performance.