High rate turbo codes for BPSK/QPSK channels

We discuss a procedure for the design of high rate turbo codes via puncturing, with applications to BPSK/QPSK channels. Rates in the form k/(k+1), 2/spl les/k/spl les/16, are considered for constituent encoders with memory size m=4. The algorithm includes the selection of constituent encoder generator polynomials, puncture patterns, and interleavers with the goal of maximizing the minimum codeword weight for weight-two and weight-three inputs. The bit error rate (BER) performance of the proposed codes are found via computer simulation and are observed in each case to be about 0.7 dB from their respective channel capacity limits at a BER of 10/sup -5/.