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:
Sep. 05, 2000
Filed:
May. 29, 1999
John E Bjornholt, Fountain Hills, AZ (US);
Sensor Technologies & Systems, Inc., Scottsdale, AZ (US);
Abstract
A system and method for generating a linear frequency sweep while also improving the phase noise characteristics of a microwave or millimeter wave signal source. The invention uses two phase lock loops. The first phase lock loop uses a linear frequency source to linearize a relatively low frequency VCO (typically around 100 MHz). The first phase lock loop has a bandwidth that is only wide enough to pass the radar modulation waveform with minimal distortion. The first phase lock loop includes a phase detector, narrow band loop filter, low noise HF VCO and a divide by M counter. The second phase lock loop is used to lock a millimeter wave VCO to the lower frequency of the low frequency VCO in the first loop. The low phase noise characteristics of this low frequency VCO are effectively impressed upon a microwave or millimeter wave, low noise high frequency VCO. The low noise high frequency VCO output from the first phase lock loop becomes the reference input for the second phase lock loop, which includes a phase detector, wide band loop filter, millimeter wave (MMW) VCO a local oscillator, mixer, amplifier/filter and a divide by R counter. The MMW VCO output is the FM-CW radar transmitted signal.