| 摘要 |
<p>Automatic/remote instrument monitoring system and method. RF transponder units (20) are operatively connected to and monitor one or more parameters of a remotely located instrument (14). The transponders (20) include RF receivers that sample received RF signals at a low duty cycle and look for a common wake-up signal transmitted from a mobile data collection unit (10). All transponders (20) receiving the common wake-up signal simultaneously energize their respective transmitters and transmit their respective messages over a predetermined RF transmission bandwidth to receivers (10B) in the mobile unit (10). The time and frequency parameters of the transponder transmission are varied in a manner such that the transmission signals of simultaneously transmitting transponders (20) differ. A plurality of RF receivers (10B) in the mobile unit are respectively tuned to collectively receive the transponder transmissions, across the entire transmission bandwidth. Decoding and signal processing circuits (10D) in the mobile receiver unit identify transmitting transponders (20) and process their respective messages.</p> |
