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:
Aug. 23, 2011
Filed:
May. 10, 2007
Kelvin Kai Tuan Yan, Oak Ridge, NC (US);
Dong-jun Yang, Greensboro, NC (US);
Kelvin Kai Tuan Yan, Oak Ridge, NC (US);
Dong-Jun Yang, Greensboro, NC (US);
RF Micro Devices, Inc., Greensboro, NC (US);
Abstract
The present invention is an RF duplex filter that is used to remove transmit signals from the receive path of a full duplex transceiver. The RF duplex filter includes a notch filter for blocking signals at a transmit frequency and a bandpass filter for enhancing signals at a receive frequency. The notch filter is formed with series resonant elements and the bandpass filter is formed with parallel resonant elements. One embodiment of the present invention may include tunable resonant elements for tuning the notch filter to a transmit frequency, tuning the bandpass filter to a receive frequency, or both. Calibration circuitry may be included in the full duplex receiver for adjusting the tunable resonant elements. The present invention includes a method for calibrating the tunable resonant elements.