Frame Synchronization in the Presence of Burst Jamming

The frame synchronization process in digital data links is very vulnerable to burst jamming. Methods of achieving frame synchronization in the presence of jamming or other large disturbances are presented. It is assumed that the disturbance can be detected at the receiver, which then erases the corresponding bits and passes this information to the synchronizer. Previous work (ref. 1) presented a synchronization algorithm designed to operate in the presence of both random erasures and background errors. This algorithm is shown to have a significant advantage over an algorithm which does not use the location information inherent in the erasure model, but this algorithm is still vulnerable to burst jamming. Two new algorithms designed to operate in the presence of burst erasures and background errors are described and evaluated. Both algorithms are robust and exhibit near optimum performance.