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:
Apr. 20, 1993
Filed:
Jun. 05, 1992
Kazuya Hashimoto, Tokyo, JP;
NEC Corporation, , JP;
Abstract
A first control circuit is provided with a temperature detector and a memory in which temperature related control data is stored. The control circuit outputs a control signal, which varies with ambient temperature, to a local oscillator which is connected with a mixer. The mixer receives an incoming radio frequency signal and a local frequency signal from the local oscillator and outputs an IF signal. The local oscillator is controlled in a manner wherein the frequency of the IF signal parallels the temperature dependent shift in center frequency of a surface acoustic wave type IF filter. The IF signal is applied to a second mixer to which a second control circuit is coupled. The second control circuit maintains the output of the second mixer at a predetermined value to compensate for the first IF's frequency shift caused by the first control circuit.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile