Patent ID: 6999548
Filing Date: 2006-02-14
Classification: H04L

Abstract:
1. A communications channel detector for determining the availability of a desired type of communications channel in a communication system having at least one communications channel, the communications channels including data streams comprising a plurality of data symbols, the channel detector comprising: a phase identifier configured to provide a plurality ‘n’ of phase measurements for each of a plurality of consecutive ones of the data symbols comprising one of the communications channels, the n phase measurements for any one of the data symbols respectively corresponding to n timing offsets from a centre of the data symbol; a phase comparator coupled to the phase identifier and configured to determine differences between the phase measurements for consecutive data symbols, each of the differences corresponding to one of the n timing offsets and determined between phase measurements corresponding to the one of the n timing offsets, to provide a plurality of phase differences for each timing offset; and a phase correlator coupled to the phase comparator and configured to determine whether or not the plurality of phase differences for at least one of the timing offsets exhibit a predetermined phase difference profile; wherein the phase identifier is configured to measure the phase of each data symbol at a number ‘m’ of the n timing offsets, and to estimate the phase of each data symbol at n-m of the n timing offsets, to thereby provide m measured phase measurements and n-m estimated phase measurements as the n phase measurements wherein ‘m’ and ‘n’ are integers.