Performance Analysis of Turbo-SPC Codes Keying Wu, Student Member, IEEE, Li Ping, Member, IEEE,

Abstract—This correspondence concerns the performance analysis of turbo-single-parity-check (SPC) codes based on the union bound of bit-error rate (BER). A treatment of the special interleavers used in turbo-SPC codes is discussed. It is shown that simple two- or four-state turbo-SPC codes with multiple component codes can perform comparably as (or even better than) the 16-state standard turbo codes. Using more complex trellis codes (with state number more than 4) appears unnecessary for such codes. Instead, performance improvement can be achieved by increasing the number of component codes, which maintains the low decoding complexity property of turbo-SPC codes. Index Terms—Free distance, parallel concatenated codes, single-parity-check (SPC) codes, turbo codes, union bound. I