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. 08, 1992
Filed:
Aug. 03, 1990
Sean M Broderick, Scottsdale, AZ (US);
Goldstar Products Co., Limited, Tempe, AZ (US);
Abstract
An IF circuit suitable for use in a cellular telephone transceiver includes a first mixer circuit receiving an rf signal and a first local oscillator signal and producing a first signal. The first signal is amplified by a first amplifier to produce an amplified second signal. A first impedance matching circuit receives the second signal and matches it to a first impedance. A double-mode resonator SAW bandpass filter with a bandwidth of approximately 30 kilohertz and a noise figure less than 5 dbm produces a filtered third signal in response to the second signal. A second impedance matching circuit is connected to receive the third signal after it is filtered by the double-mode resonator SAW bandpass filter, and impedance matches it to a second impedance. A second amplifier receives and amplifies the third signal. A second mixer circuit receives the fourth signal and a second local oscillator signal, and produces an IF signal.