Methods and apparatus for evaluating downhole conditions with RFID MEMS sensors
US9494032B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 2013 |
| Grant date | Nov 15, 2016 |
| Priority date | — |
| Expiry date | Nov 18, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/07749
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A radio frequency identification (RFID) tag can include a die attached to an inductive-capacitive (LC) circuit including a capacitive element coupled to an inductive element. The LC circuit can have a resonant frequency that varies according to properties of fluid proximate the RFID tag. The RFID tag can further include a coating material disposed around the die to form an outer surface of the RFID tag. The coating material may have a thickness over a portion of the LC circuit, to permit a conductivity property of a fluid proximate the outer surface to affect the resonant frequency of the LC circuit such that the resonant frequency shifts to a second resonant frequency. Additional apparatus, systems, and methods are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.