Method for automatic mode selection for a dual-mode telephone handset for use in a cellular mobile telephone system and in a wireless telephone system
US5504803A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 1993 |
| Grant date | Apr 2, 1996 |
| Priority date | — |
| Expiry date | Aug 2, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W88/06
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A personal communications system permits a wireless handset to access either a cellular mobile telephone system (CMTS) or a private wireless telephone system (WTS) which shares the CMTS frequency band by utilizing those CMTS channels which are idle in the area serviced by the WTS. The wireless handset automatically selects between the WTS and CMTS operating modes by maintaining a list of previously accessed WTS control channels and periodically scanning that list for a WTS available at the location of the handset. If a WTS control channel is not found in that list, then the handset periodically scans all possible WTS control channels for the purpose of registering on an available WTS. If no WTS is found, then the handset switches to CMTS mode. The scanning methodology permits the wireless handset to rapidly lock on to an available WTS which will provide service to the handset, so as to reduce the possibility of the wireless handset missing incoming paging signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.