Antenna with variable phase shift
US6774851B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2002 |
| Grant date | Aug 10, 2004 |
| Priority date | — |
| Expiry date | Sep 27, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q3/46
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a reflectarray antenna. The reflectarray antenna comprises a dielectric substrate layer disposed on a ground plane. An array of radiating elements such as microstrip patches of similar size are arranged into a regular lattice configuration on the top surface of the substrate layer. A periodic configuration of slots of variable size are provided at the bottom surface of the substrate layer. A required phase shift at each position on the reflectarray surface is obtained by adjusting the slot length on the ground plane. The incident wave from the feed excites the dominant mode on the microstrip patches The presence of slots acts as an inductive loading of the patches, which introduces a phase shift in the patch response. The inductance of each slot depends on its length. In accordance with an aspect of the invention the phase shift of the individual microstrips is modified by shining an appropriate optical image onto each individual slot element, thereby altering the radiation characteristics of the reflectarray. This approach is highly advantageous for dynamic beam scanning and beam shaping.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.