Low-power circuit and method for providing rapid frequency lock in a wireless communications device
US5767791A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 1996 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Jul 9, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S128/903
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A two-way medical telemetry system is provided for displaying and monitoring, at a central location, physiologic and other patient data of multiple, remotely-located patients. The system comprises multiple battery-powered remote telemeters, each of which is worn by a respective patient, and a central station which receives, displays and monitors the patient data received (via RF) from the remote telemeters. The telemeters communicate with the central station using a two-way TDMA protocol which permits the time sharing of timeslots, and which uses a contention slot to permit telemeters to transmit service requests to the central station. Two-way spacial diversity is provided using only one antenna and one transceiver on each remote telemeter. The remote telemeters include circuitry for turning off the active transceiver components thereof when not in use (to conserve battery power), and include circuitry for performing a rapid, low-power frequency lock cycle upon power-up. The system has multiple modes of operation, including a frequency hopping (spread spectrum) mode and a fixed frequency mode, both of which preferably make use of the 902-928 MHz ISM band. Patient locators are prov…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.