Apparatus and method for interrogation of passive sensors
US7034661B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 2002 |
| Grant date | Apr 25, 2006 |
| Priority date | — |
| Expiry date | Apr 9, 2023 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60C23/0483
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A monitoring system, particularly suitable for monitoring conditions (e.g. pressure or temperature) of a vehicle tire comprises a passive sensor (102, 104), an antenna (106) associated with said passive sensor, and switching means (108) for controlling the connection between the passive sensor and the antenna such that, in a first state of said switching means, said antenna is prevented from transmitting a signal generated by the passive sensor, and, in a second state of said switching means, said antenna is permitted to transmit a signal generated by the passive sensor. The switching means is operated remotely by means of a control signal. The control signal may be derived from the sum or difference of RF signals (F1 and F2) applied to a filter (112) In alternative embodiments the control signal is the modulating frequency of an AM or FM modulated radio signal or a radio signal carrying a digital code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.