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:
May. 20, 2014
Filed:
Oct. 02, 2012
Rf Micro Devices (Cayman Islands), Ltd., Greensboro, NC (US);
Malcolm Smith, San Jose, CA (US);
Ying Shi, Saratoga, CA (US);
RF Micro Devices (Cayman Islands), Ltd., George Town, KY;
Abstract
In transmitter modules or power amplifier (PA) modules there is at least a possible path for a second and even a third harmonic of a low band to crossover unfiltered into the high band path and reach the antenna and hence cross band isolation is necessary. Forward isolation is necessary in order to limit the input crossing over the PAs into the antenna port. According to the methods and the circuits such cross band isolation and forward isolation is improved by detuning the filter and matching network at the output of the PA. The circuit comprises a trap at the harmonic frequencies of the low band thereby at least reducing the impacts of the cross band and forward isolation.