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. 04, 2000
Filed:
Sep. 16, 1997
Telefonaktiebolaget LM Ericsson, Stockholm, SE;
Abstract
A frequency synthesizer has a phase locked loop, a .DELTA..SIGMA. modulator, and a filter. The phase locked loop includes a frequency divider that controls the frequency of the phase locked loop output signal. The output of the .DELTA..SIGMA. modulator is fed through the filter and the output of the filter is used to control a division factor in the frequency divider. Compensation may be performed at the input to the .DELTA..SIGMA. modulator in order to compensate for the filtering performed between the .DELTA..SIGMA. modulator and the frequency divider. The filter may be used to reduce quantization noise in an input to the frequency divider, and thereby reduces phase noise in an output of the phase locked loop.