Stream-oriented turbo codes

This work considers the design and performance of a stream-oriented approac h to turbo codes which avoids the need for data framing. The stream paradig m applies to both serial and parallel turbo codes using continuous, free-ru nning constituent encoders along with continuous, periodic interleavers, A stream-oriented turbo code based on parallel concatenated convolutional cod es (PCCC) is considered and interleaver design criteria are developed for b oth block and nonblock periodic interleavers, Specifically, several nonbloc k interleavers, including convolutional interleavers, are considered. Inter leaver design rules are verified using simulations where it is shown that n onblock interleavers with small-to-moderate delay and small synchronization ambiguity can outperform block interleavers of comparable delay. For large -delay designs, nonblock interleavers are found which perform within 0.8 dB of the capacity limit with a synchronization ambiguity of N = 11.