Procedure, system and device for error detection in OFDM wireless communication networks without decoding full forward error correction

摘要

A method for detecting errors in an information packet (13) received by an OFDM receiver (14) in an orthogonal frequency division multiplexing system, OFDM, in which the information packet is encoded using an error correction technique forward, FEC, said FEC technique involves in the receiver an iterative decoding procedure, the method comprising the following steps carried out in the receiver (14): a) performing a number of iterations, Niter, of the correction decoding technique of forward errors in the received packet of length NFEC bits, in which Niter is less than the minimum number of iterations required for a complete FEC decoding in the signal-to-noise ratio plus intended interference, SINR; b) obtain a value of the logarithmic a posteriori probability relation, LLR, for each bit decoded after Niter decoding iterations FEC; the method being characterized by: c) obtaining the probability that the block of bits decoded after Niter iterations has an error, represented as the block error probability of the received packet after Niter iterations, BLEPNiter 0, and the density function of probability of said block error probability, represented as fBLEPNiter (BLEPNiter) from said posterior LLR values, in which fBLEPNiter (BLEPNiter) is obtained as a transformation of LLR values a posteriori; d) estimating a block error rate that would correspond to the packet received in the complete FEC decoding, based on the signal-interference plus post-detection noise, SINR, of the received bits; e) obtain a variable decision value for the block error decisions, Z, by means of the following expression: ** Formula ** and f) determine whether the received packet has errors or not, comparing said decision variable with said error rate of estimated block.