AN ALGORITHM FOR IDENTIFYING RATE (N-1) N CATASTROPHIC PUNCTURED CONVOLUTIONAL ENCODERS/

It is known that both Viterbi and sequential decoding of convolutional codes can be greatly simplified by employing punctured convolutional codes, which are obtained by periodically deleting a part of the bits of a low-rate convolutional code, Even if the original low-rate convol utional code is noncatastrophic, some deleting maps may result in rate (n - 1)/n catastrophic punctured encoders, An algorithm is presented to identify such encoders when the original rate 1/b encoder is antipo dal, The major part of the algorithm solves a linear equation of v + 1 variables, where v is the constraint length of the original rate 1/b code.