Swept frequency radar system employing phaseless averaging
US4268828A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 1979 |
| Grant date | May 19, 1981 |
| Priority date | — |
| Expiry date | Sep 19, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02A90/10
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Described herein is a microwave radar system which employs heterodyned swept frequency at approximately two millisecond sweep intervals. The power source is a reliable solid state, low power device such as a Gunn diode. The heterodyned difference frequency signals are converted to digital form, transformed into the frequency domain by means of a Fourier power transform, and then averaged by computer processing. Performing the Fourier power transform before averaging enables the processing of quasi-incoherent data whereby signal-to-noise ratio improvement is a function of the square root of the average number of samples taken. High-speed processing is used to off-set the loss of statistical averaging of phase-coherent data which cannot be preserved because of target motion. Thus, the sequence of the power transform allows phase-less averaging over the entire collection period. Complementary elements including signal isolation and stability, through interdependent design features of the antenna and circulator, permit the use of low-power CW radar which minimizes danger to ecology and human safety. Thus, the invention has particular applicability to the analysis of clouds, the extract…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.