Technique for finding a starting state for a convolutional feedback encoder

Abstract

A convolutional feedback encoder uses a shift type shift register with both feed-forward and feedback circuit structures to process and encode a fixed length information sequence. The encoder is configured, through careful selection of the feedback coefficients, so as to achieve a tail-biting mode of operation. Tail-biting means that the state of the encoder prior to the input of the first uncoded data bit is the same as the state of the encoder upon input of the last uncoded data bit. The starting state of the encoder is found by linearly combining data bits in the information sequence. The linear combinations are determined by a selection matrix or selection vector which is derived from the feedback coefficients of the encoder.

Dependencies are inferred from the claim text.