Object detection and location system
US4901084A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 1988 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | Apr 19, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q15/248
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A millimeter wave object detection and location system is disclosed comprising a source generating a millimeter wave signal which is divided into an illumination beam, directed onto a field of view, and a local oscillator portion, mixed with radiation reflected from objects in the field of view. The mixing is performed in a staring array of mixer/detector elements which need not be mechanically or electronically scanned to generate signals responsive to the entire field of view. The detected signal from each element is directly responsive to a portion of the field of view. The oscillator signal is preferably linearly polarized, and a polarizing grid is used to separate the local oscillator signal and illumination beam and direct them in a simple and efficient manner. A twist reflector may also be used to rotate the polarization of a portion of the beam to direct it onto the mixer/detector array for mixing with the received signal from the field of view. Improved constructions of millimeter wave source and mixer/detector elements are also disclosed, which greatly simplify construction of the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.