Dual frequency radar receiver
US4313216A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 1981 |
| Grant date | Jan 26, 1982 |
| Priority date | — |
| Expiry date | Feb 4, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S7/285
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A radar receiver for detecting quasi-harmonically related radar signals includes an antenna system (10) having a mixer (15) included therein. One harmonic from a local oscillator (20) mixes with a signal at a first frequency to produce an intermediate frequency, and another harmonic of the local oscillator mixes with an input signal at a second frequency also to produce an intermediate frequency. A second mixer (30) and local oscillator (40) may be provided. A bandwidth limited signal detecting system preferably includes a band pass filter (50), a limiting IF amplifier (55) and a frequency discriminator (60). The frequency of either the first or second local oscillator is repeatedly varied by a sweep generator (35) to insure that the presence of a radar signal will pass through the band pass filter (50) and be detected. A low pass filter (65) reduces the noise component output of the discriminator, and a comparator (70) provides output pulses whenever a radar signal within either of the quasi-harmonically related frequency ranges is detected. Radar signals at the two frequencies can be distinguished from each other by the time between the pulses generated as detected by a circuit i…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.