Dynamic impedance matching in RF resonator cavity
A method for matching an impedance of a system comprising a cavity and one or more feeds to an impedance of one or more sources of electromagnetic radiation irradiating a plurality of frequencies into the cavity via the feeds, comprising: determining a plurality of s-parameter of the system for a frequency band; determining the system impedance based on the s-parameters; and modifying the system impedance according to the difference between the impedance of the system and the impedance of the source.
1. A method for improving absorption of electromagnetic energy provided by a source at a plurality of frequencies within a frequency band into a cavity via at feeds in a system comprising the cavity and the feeds and circuitry, comprising:
(a) determining s-parameters of the cavity and the feeds for a plurality of frequencies in the frequency band;
(b) determining an absorption intensity characteristic of an entirety of the frequency band, based on the s-parameters determined for the plurality of frequencies in the frequency band; and
(c) improving, utilizing the circuitry, the absorption intensity characteristic of the frequency band by changing phases of RF signals directed to the feeds based on the determined s-parameters,
wherein the determining s-parameters comprises:
irradiating one of more frequency bands into the cavity by one or more of the at least one feed;
measuring reflected energy by one or more of the at least one feed; and
determining one or more relations between the reflected energy and the irradiated energy at one or more frequency bands.
2. The method according to claim 1 , wherein the improving the absorption intensity characteristic comprises maximizing the absorption intensity characteristic.
3. The method according to claim 2 , wherein the maximizing comprises maximizing within a threshold.
4. The method according to claim 1 , wherein the improving the absorption intensity characteristic is repeated a plurality of times.
5. The method according to claim 1 , wherein changing phases of the RF signals is performed responsive to a predefined change in the absorption of electromagnetic energy at one or more frequencies.
6. An electromagnetic radiation heater configured to perform the method of claim 1 .
7. The method according to claim 1 , wherein the plurality of frequencies comprises RF radiation frequencies in a microwave range.
8. The method according to claim 1 , wherein the cavity is a resonant cavity.
9. The method according to claim 1 , wherein the cavity contains a removable added object.
10. The method according to claim 9 , wherein the removable added object is heated by the electromagnetic energy.
11. The method according to claim 10 , wherein the removable added object comprises food.
12. The method of claim 1 , wherein the absorption intensity characteristic is an average of absorption intensities across the frequency band.
13. The method of claim 1 , wherein the absorption intensity characteristic is a variance of absorption intensities across the frequency band.