Method for a radiotelephone to scan for alternate radiotelephone systems

A method for allowing a radiotelephone to scan for alternate radiotelephone systems using a single receiver, each radiotelephone system having a plurality of cells for providing radiotelephone service to a radiotelephone within a corresponding geographic area, each cell having paging and voice communication and a radio coverage area established by fixed site base stations, and each base station operable to send paging messages to radiotelephones, the method comprising the steps of:

• powering up the radiotelephone;
• scanning for available technologies for service;
• registering and camping the radiotelephone on a preferred radiotelephone system;
• establishing by the radiotelephone system whether to enable alternate technology scanning for the radiotelephone;
• and
• if alternate technology scanning is disabled:
• the radiotelephone receiving paging messages from the base station;
• the radiotelephone acknowledging to the base station paging messages addressed to the radiotelephone;
• if alternate technology scanning is enabled;
• the radiotelephone scanning for an alternate technology for service;
• the base station concurrently repeating any paging messages addressed to the radiotelephone during performance of the scanning step;
• the base station ignoring a lack of acknowledgement from the radiotelephone for paging messages addressed to the radiotelephone and retaining the radiotelephone on an active list.

A method for allowing a radiotelephone to scan for alternate radiotelephone systems using a single receiver, each radiotelephone system having a plurality of cells for providing radiotelephone service to a radiotelephone within a corresponding geographic area, each cell having paging and voice communication and a radio coverage area established by fixed site base stations, and each base station operable to send paging messages to radiotelephones, the method comprising the steps of:

• powering up the radiotelephone;
• scanning for available technologies for service;
• registering and camping the radiotelephone on a preferred radiotelephone system;
• establishing by the radiotelephone system whether to enable alternate technology scanning for the radiotelephone;
• detecting if service has been lost on the current network whereupon continuing at the previous scanning step;
• and
• if alternate technology scanning is disabled:
• the radiotelephone receiving paging messages from the base station;
• the radiotelephone acknowledging to the base station paging messages addressed to the radiotelephone;
• if alternate technology scanning is enabled;
• the radiotelephone scanning for an alternate technology for service;
• the base station concurrently repeating any paging messages addressed to the radiotelephone during performance of the scanning step;
• the base station ignoring a lack of acknowledgement from the radiotelephone for paging messages addressed to the radiotelephone and retaining the radiotelephone on an active list.