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:
Mar. 30, 1999
Filed:
Mar. 17, 1998
Jeffrey Schlang, Raleigh, NC (US);
Ron Boesch, Morrisville, NC (US);
Charles Gore, Durham, NC (US);
Aristotle Hadjichristos, Apex, NC (US);
Ericsson Inc., Research Triangle Park, NC (US);
Abstract
According to a second embodiment of the invention, a mobile phone receiver comprises a first down converter using a first local oscillator frequency which can be tuned in frequency steps by a programmable digital frequency synthesizer PLL which is locked to a reference frequency. The first down converter converts received signals to a first IF for filtering. A second down converter using a second local oscillator converts first IF signals to a second IF. The second local oscillator frequency is generated using a second digital frequency synthesizer PLL which locks the second oscillator to the reference frequency. A third down converter mixes the transmit frequency with the first local oscillator frequency to produce a lock frequency. A third digital frequency synthesizer PLL compares the lock frequency and the reference frequency to control generation of the transmit frequency.