Patent ID: 7643454

Claim:
A method of avoiding multiple detections of a random access channel (RACH) preamble in a communication system, comprising: detecting, within a set of access slots, a given sub-set of available preamble signatures corresponding to a RACH preamble of a user so as to avoid multiple detections of the same RACH preamble in a given access slot, the detecting includes, listening for a given sub-set of RACH sub-channels which use the same access slot in order to detect the preamble, the detected preamble having a preamble signature of a given user that is using one of the RACH sub-channels in the given sub-set of RACH sub-channels to access the communication system; and assigning each of a plurality of channel elements at a Node B a sub-set of the set of access slots to monitor by assigning each of the plurality of channel elements a sub-set of the RACH sub-channels to monitor, one of the sub-sets of the RACH sub-channels being the given sub-set of RACH sub-channels and the Node B being configured to switch between multi-sector/single cell operations and single sector/multi-cell operations.