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:
Oct. 31, 2006
Filed:
Jun. 06, 2002
Hee Wong, San Jose, CA (US);
Shu-ing Ju, Palo Alto, CA (US);
Michael Schwartz, San Jose, CA (US);
Robert K. Butler, Issaquah, WA (US);
Hee Wong, San Jose, CA (US);
Shu-Ing Ju, Palo Alto, CA (US);
Michael Schwartz, San Jose, CA (US);
Robert K. Butler, Issaquah, WA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A radio frequency (RF) demodulation circuit comprising a harmonic rejection mixing stage capable of receiving and mixing an incoming radio frequency (RF) signal having a frequency RF and a reference local oscillator (LO) signal having a frequency LO and generating an output signal in which out-of-band harmonic signals are suppressed. The harmonic rejection mixing stage comprises 1) a multiphase local oscillator (LO) generator for receiving the reference LO signal and generating M phase-shifted local oscillator signals having frequencies LO and 2) M mixers, each of the M mixers receiving the incoming radio frequency signal and one of the M phase-shifted local oscillator signals. Each of the M mixers generates a subcomponent signal. The subcomponent signals are then scaled and combined to produce the output signal.