Patent ID: 9496985
Filing Date: 2016-11-15
CPC Classification: G11B,H04B,H04L

Claim Text:
1. A decoding system, comprising: a modulator which modulates user data having a predetermined bit length by using a modulation rule which converts the user data in accordance with characteristics of a transmission path into a modulation pattern having a bit length equivalent to or different from the predetermined bit length so as to disperse information on an arbitrary bit of the user data into plural bits of the modulation pattern; a regenerator which generates a regenerative signal from a signal obtained by transmitting the user data after modulation by the modulator through the transmission path; a transmission path decoder which generates signals as generation signals corresponding to the modulation pattern, and calculates distances between the regenerative signal and the generation signals in an interval having a length fixedly or dynamically determined depending on the bit length of the modulation pattern, the signals being generated by taking into account the characteristics of the transmission path with respect to the modulation pattern; and a demodulator which calculates reliability information for each bit of the user data based on the distances between the regenerative signal and the generation signals in the interval, and estimates each bit of the user data based on the calculated reliability information, wherein the transmission path has characteristics to disperse an arbitrary element of a signal transmitted through the transmission path into plural components of the regenerative signal, the transmission path decoder generates k (k is a positive integer) generation signals, and respectively calculates k distances between the regenerative signal and each of the k generation signals in the interval, and the demodulator uses the k distances calculated by the transmission path decoder to respectively calculate likelihood that each bit of the user data is 1 and likelihood that each bit of the user data is 0 by Formula (A), and calculates the reliability information by Formula (B): wherein Formula (A) is: wherein Formula (B) is: where x is 0 or 1, p wherein a middle part of Formula (A) is: wherein the middle part of Formula (A) expresses a sum of the probabilities of the modulation patterns where d