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:
Dec. 24, 1996
Filed:
Jul. 31, 1995
Abstract
A first oscillator includes: a ring resonator; an oscillation circuit having a negative resistance active circuit coupled to a first point on the ring resonator for oscillating at an oscillation frequency and resonating the resonator; an output terminal, coupled to a second point on the ring resonator where a voltage is substantially zero with respect to the predetermined frequency when the ring resonator resonates, for outputting a resonant frequency signal, wherein even order harmonic components are outputted with the fundamental component suppressed. A second oscillator includes a ring resonator having points A to D equidistantly dividing the ring resonator, first and second oscillation circuits coupled to the points A and B respectively, first and second grounding capacitors having capacitance equivalent to those of the first and second oscillation circuits. Thus, two independent oscillators which do not affect each other are provided with a single resonator. In the first and second oscillators, grounding capacitors, a resonant capacitor may be provided to miniaturize the oscillator. Variable capacitances may be provided to prevent the point from moving with a change in the controlled oscillation frequency. Frequency synthesizers and communication apparatus including the first or second oscillator are also disclosed.