Patent ID: 6675342
Filing Date: 2004-01-06
Classification: H03M

Abstract:
A method of iteratively decoding a sequence of received signals, representative of systematic convolutional encoded elements generated by a parallel-concatenated encoder from a source of original digital data elements, into decoded elements corresponding to the original digital data elements, the method comprising the steps of:(a) applying a received input information sequence X(k), a first received convolutional code sequence Y(k) corresponding to the input information sequence, and a first a priori information sequence to a first probability-based decoder to generate a first extrinsic information sequence; (b) applying an interleaved received input information sequence Xâ€²(k), a second received convolutional code sequence Yâ€²(k) corresponding to the interleaved input information sequence, and a second a priori information sequence to a second probability-based decoder to generate a second extrinsic information sequence; (c) applying the first a priori information sequence and the first extrinsic information sequence to a first combinatorial element to generate a first reference sequence; (d) applying the first reference sequence to a first quantizer to generate a first quantized reference sequence; (e) applying the second a priori information sequence and the second extrinsic information sequence to a second combinatorial element to generate a second reference sequence; (f) applying the second reference sequence to a second quantizer to generate a second quantized reference sequence; (g) applying the first quantized reference sequence to a first interleaver to generate an interleaved first quantized reference sequence; (h) applying the first quantized reference sequence to a first comparator element; (i) applying the interleaved first quantized reference sequence to a second comparator element; (j) storing the second quantized reference sequence in a data storage location; (k) applying the second quantized reference sequence to the second comparator element; (l) applying the second quantized reference sequence to a first de-interleaver element to generate a de-interleaved second quantized reference sequence; (m) applying the de-interleaved second quantized reference sequence to the first comparator element; (n) comparing the de-interleaved second quantized reference sequence with the first quantized reference sequence within the first comparator element; (o) comparing the interleaved first quantized reference sequence with the second quantized reference sequence within the second comparator element; (p) repeating steps (a) through (o) until the compared signals within the first and second comparator elements are identical; and (q) generating substantially error-free decoded elements when the compared signals within the first and second comparator elements are identical.