Off-channel frequency discriminator circuit for use in a precision distance measuring equipment (DME/P) receiver
US4646097A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 6, 1985 |
| Grant date | Feb 24, 1987 |
| Priority date | — |
| Expiry date | May 6, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/787
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A precision distance measuring equipment (DME/P) receiver for detecting an RF signal including at least one interrogation pulse is described. The DME/P receiver includes first and second signal processing channels. The first processing channel includes a wideband filter, of bandwidth BW1, for receiving the processed RF signal and in response thereto generating a wideband (FA) mode signal proportional to the logarithm thereof. The second signal processing channel includes a narrowband filter, of bandwidth BW2, for receiving the processed RF signal and in response thereto generating a narrowband (IA) mode signal proportional to the logarithm thereof, the bandwidth BW2 of the narrowband filter being within the bandwidth BW1 of the wideband filter. A frequency discriminator circuit receives samples of the FA and IA mode signals from the first and second signal processing channels, and in response thereto generates a control signal when the pulse has a frequency within the bandwidth BW1 but outside the bandwidth BW2, the control signal representing an "off-channel" condition. In operation, gating circuits are connected to receive the control signal from the frequency discriminator circu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.