Patent ID: 6023462
Filing Date: 2000-02-08
Classification: H04J,H04M,H04W

Abstract:
A method for operating a fixed wireless system having a radio base unit (RBU) that uses a code division multiple access (CDMA) airlink for communicating with a plurality of subscriber units (SUs) within a coverage area of the RBU, comprising steps of:establishing, from a set of pseudonoise (PN) spreading codes, a first subset of PN spreading codes that are currently assigned to SUs and a second subset of PN spreading codes that are currently not assigned to SUs;ranking the PN spreading codes from the second subset of non-assigned PN spreading codes by an amount of interference experienced by the use of each non-assigned PN spreading code, wherein the step of ranking includes the steps of applying, in turn, individual ones of the PN spreading codes from the second set of non-assigned PN spreading codes to a correlator and determining an amount of interference within a reception frequency band that correlates with the applied one of the PN spreading codes, thereby determining an amount of unwanted energy that is output from the correlator resulting from the use of the PN spreading code within the reception frequency band; andassigning, to a SU requiring a PN spreading code, a PN spreading code from the second set of non-assigned PN spreading codes that is ranked as having a least amount of interference.