Self Synchronizing Digital Scramblers

A known way of scrambling binary data for security purposes is by adding to it, bit by bit, a pseudorandom sequence A. Synchronization is established by providing the descrambler with the states of A\´s generator. It is shown here how for data transmitted in blocks, the states of the generator can be recovered at any instant which enables self-synchronization. If the block length is and the generator of A consists of an -stage register, there is a delay of bits, between sync lost and sync recovery.