Repeater station for augmenting the coverage area of a paging system
US5995804A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 1997 |
| Grant date | Nov 30, 1999 |
| Priority date | — |
| Expiry date | Jan 16, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D30/70
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A low power miniature repeater station is located on a vehicle such as a train, cargo ship, cruise ship or other vehicle which is expected to carry multiple paging receivers. The repeater station receives paging messages that originate as satellite signals and rebroadcasts them in the immediate vicinity of the vessel. The rebroadcast may typically be over a single FM carrier frequency or in the form of a subcarrier signal. The repeater includes an FM scanning receiver that samples the radio band and enables the rebroadcast of signals only if FM subcarrier signals are not detected within the vicinity of the vehicle. As the vehicle re-approaches a populated area, continued scanning of the radio band eventually detects the presence of subcarrier signals and shuts down the repeater to ensure that it will not interfere with licensed terrestrial broadcasters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.