Patent ID: 8509104
Filing Date: 2013-08-13
Classification: H04J,H04L

Abstract:
1. A method of identifying, by a receiver of signals transmitted via a channel of a wireless communications system, a sequence of received signals as one of a number of known orthogonal sequences, comprising the steps of: receiving said sequence of received signals serially over a given time interval; receiving, in addition to said sequence of received signals, at least one known signal at a time instant in said given time interval; dividing said sequence of received signals into a first part comprising signals received before said time instant and a second part comprising signals received after said time instant, wherein the signals in the first part are distorted by a phase shift having a first polarity, and the signals in the second part are distorted by a phase shift having a second polarity that is opposite that of the first polarity; calculating from said sequence of received signals a modified received sequence by replacing at least one of the received signals from one of said parts by their complex conjugate values; correlating the modified received sequence with each one of the number of known orthogonal sequences to obtain a correlation result for each of said known sequences; and identifying the sequence of received signals as the known orthogonal sequence having the largest correlation result.