RFID tag circuits tags and methods for backscattering with controllable admittance
US7990249B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 2007 |
| Grant date | Aug 2, 2011 |
| Priority date | — |
| Expiry date | Jun 1, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/0715
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
RFID tag circuits, tags, and methods are provided for backscattering a received RF wave using a controllable admittance difference between the ON state and the OFF state. The admittance difference is controlled responsive to a control signal. In some embodiments, the control signal is generated responsive to a command. In others, the control signal is generated responsive to detecting the power level of the received RF wave. In those, the inherent behavior of the admittance difference can be shaped as desired. For example, it can be such that the backscatters with advantageously more power when it is away from the reader, and with less power when it is close to the reader, so as to meet regulatory requirements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.