Methods for selecting cells in cellular telephone systems

摘要

User equipment such as cellular telephones and other wireless electronic devices may communicate wirelessly with 2G and 3G cells in a cellular network. The cellular network may broadcast a list of primary scrambling codes corresponding to 3G cell sites that are potentially available for wirelessly communicating with the user equipment. The user equipment may perform an evaluation of primary scrambling code pilot signal strengths for each of the primary scrambling codes in the list. The user equipment may also maintain a record whenever a more extensive full primary scrambling code scan fails. If the evaluation reveals that at least one signal strength is sufficient, the cellular telephone may establish a corresponding 3G wireless link. If the evaluation does not identify any sufficiently strong 3G cells, a full pilot signal scan may be performed, provided that no full scans have failed within a predetermined time interval before the current time.