Method and apparatus for tracking a resonant frequency
US7089794B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 2003 |
| Grant date | Aug 15, 2006 |
| Priority date | — |
| Expiry date | Apr 15, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03C1/46
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An arrangement for tracking resonant frequency of electrically resonant structures through a single channel includes a variable frequency oscillator associated with each resonant structure which provides an excitation signal of a variable frequency encompassing a possible resonant frequency of the associated resonant structure. Coupling device(s) are provided which connect each variable frequency oscillator to said resonant structure(s). An I-mixer is provided for each oscillator which forms a synchronous detector, a first input of each I-mixer being connected to its associated oscillator and a second input being connected to the coupling device, each I-mixer mixing the excitation signal from the associated variable frequency oscillator with a response signal generated by the resonant structure(s) in response to each excitation signal. The output of each I-mixer is filtered to remove sum products of the excitation and response signals, thereby leaving an amplitude modulation component of the signal, which is processed in a control loop to track the resonant frequency of each resonant structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.