The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 26, 1982
Filed:
Feb. 04, 1981
James L Jaeger, West Chester, OH (US);
Michael D Valentine, Cincinnati, OH (US);
Cincinnati Microwave, Inc., Cincinnati, OH (US);
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 including a one-shot (110), a counter (120), a clock (115), gates (125, 130, 135, 140), and indicators (145, 150).