Method and apparatus for encoding and decoding data

摘要

A method and apparatus for selecting interleaver sizes for turbo codes is provided herein. During operation information block of size K is received. An interleaver size K′ is determined that is related to K″, where K″ from a set of sizes; wherein the set of sizes comprise K″=ap×f, pmin≦p≦pmax; fmin≦f≦fmax, wherein a is an integer and f is a continuous integer between fmin and fmax, p takes integer values between pmin and pmax, a>1, pmax>pmin, pmin>1. The information block of size K is padded into an input block of size K′ using filler bits, if needed. Encoding is performed using the original input block and the interleaved input block to obtain a codeword block using a turbo encoder. The codeword block is transmitted through the channel.

主权项

1. A method for operating a turbo encoder, the method comprising the steps of:
receiving an information block of size K; determining an interleaver size K′ equal to K where K is from a set of sizes; wherein the set of sizes comprise K=ap×f, pmin≦p≦pmax; fmin≦f≦fmax, wherein a is an integer, f is a continuous integer between fmin and fmax, and p takes integer values between pmin and pmax, a>1, pmax>pmin, pmin>1; interleaving the information block using an interleaver of size K′, wherein the step of interleaving the information block comprises the step of using a permutation π(i)=(f1×i+f2×i2)mod K′, where 0≦i≦K′−1 is a sequential index of symbol positions after interleaving, π(i) is a symbol index before interleaving corresponding to position i, K′ is an interleaver size in symbols, and f1 and f2 are factors defining the interleaver; encoding the original information block and the interleaved information block to obtain a codeword block; and transmitting the codeword block through the channel.