Cellular radiotelephone system having colocated base sites

摘要

A cellular radiotelephone system (101) includes a control terminal (420) coupled by in trunks and out trunks to the telephone central office (110) and by data and voice lines to base sites (411-416) in corresponding cells (401-406) for providing telephone coverage to mobiles located throughout a geographical area. In order accommodate additional voice channels in each cell (401-405), base sites (441-446) are colocated with corresponding existing base sites (401-405). Paging/access channels are assigned to existing base sites (411-416) for paging mobiles for all outgoing originations and processing all incoming mobile originations and page responses. Access-only channels are assigned to colocated base sites (441-446) for processing mobile originations and page responses transferred thereto by a directed retry message from corresponding existing base sites (401-405). The additional voice channels assigned to colocated base sites (441-446) may be voice channels in new radio frequency bands allocated to cellular radiotelephone systems. If both existing and additional voice channels are assigned to existing base sites (411-416) and/or colocated base sites (441-446), new voice channels are assigned to requesting mobiles before assigning existing voice channels, provided that the requesting mobile operates on both existing and new voice channels.