Patent ID: 6556829
Filing Date: 2003-04-29
Classification: H04W

Abstract:
A method of operation of a mobile communications network for communication with a plurality of mobile stations, the network comprising a plurality of base stations, each base station being associated with a particular cell, each cell being identified within the network by a colour code signal transmitted by a base station within the cell, and each base station within a cell communicating with the respective mobile stations on an operating frequency chosen from a preselected number of available frequencies, the number of cells in the network being greater than the number of available frequencies, the method comprising:sending control signals to each respective mobile station, instructing it to make signal quality measurements on a plurality of frequencies, the plurality of frequencies remaining generally the same over time, and being the operating frequencies of neighbouring cells said neighbouring cells being the cells to which the mobile station may execute a handover if required; sending control signals to each respective mobile station, instructing it to make signal quality measurements on at least one additional frequency in use within the network, the additional frequency not being associated with any neighbouring cells, the additional frequency being changed frequently; receiving detected signal quality measurements made by each respective mobile station on the additional frequency; receiving a detected colour code associated with any signal detected on the additional frequency, the colour code being detected by one of the mobile stations; determining, on the basis of the detected colour code, the cell from which the signal detected on the additional frequency originated; and determining on the basis of the signal quality measurements whether said cell, from which the signal detected on the additional frequency originated, can be designated as a neighbouring cell to which a mobile station may execute a handover.