Scanning beam receiver system with coherent post-detection signal processing
US4107686A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 25, 1977 |
| Grant date | Aug 15, 1978 |
| Priority date | — |
| Expiry date | Jan 25, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S1/44
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A receiving system for a time-reference, scanning beam radio guidance system in which the scanning beam, an offset frequency reference signal and a time reference signal are provided from the ground beacon location. The receiving system includes a first detector responsive to the scanning beam and offset reference signals to provide a spectrum centered about the offset signal. A bandpass filter with sloping skirts on both sides of the center (offset) frequency provides tapering, with decreasing amplitude response on each side of the center frequency, the width of the spectrum being a function of the aperture of the beam transmitting antenna at the ground beacon. Angular information is determined by thresholding the beam signal to find two points on either side of beam center, averaging these times and comparing with the time-reference signal to air-derive angular navigational data, especially for aircraft landing approach systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.