Patent ID: 7164918
Filing Date: 2007-01-16
Classification: H04W

Abstract:
1. A radio communication system having a random access channel for transmissions from a secondary station to a primary station, the secondary station having means for requesting allocation of a random access channel resource by transmission of an access preamble encoded with a first signature selected from a first set of signatures and the primary station having means for receiving the access preamble, for determining the first signature and for transmitting an access acknowledgement encoded with a second signature selected from a second set of signatures indicating whether the requested resource is available; means for determining at which of a plurality of available time offsets the access preamble was transmitted; and means for receiving a contention resolution preamble, transmitted by the secondary station in response to reception of the access acknowledgement, for determining at which of the plurality of available time offsets the contention resolution preamble was transmitted, and for transmitting a contention resolution acknowledgement indicating whether the secondary station has been granted access to the requested resource, wherein the choice of first signature provides further information regarding the resource allocation request and wherein each signature of the second set corresponds to a plurality of signatures in the first set.