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:
Jul. 26, 2005
Filed:
May. 21, 2003
Peter Y. Cheung, Chino Hills, CA (US);
David L. Crampton, Rossmoor, CA (US);
Jennifer Y. Vollbrecht, Torrance, CA (US);
Kuang Yung Liu, Los Angeles, CA (US);
Lauriston Chin Wah, Manhattan Beach, CA (US);
Peter Y. Cheung, Chino Hills, CA (US);
David L. Crampton, Rossmoor, CA (US);
Jennifer Y. Vollbrecht, Torrance, CA (US);
Kuang Yung Liu, Los Angeles, CA (US);
Lauriston Chin Wah, Manhattan Beach, CA (US);
The Boeing Company, Chicago, IL (US);
Abstract
A method and apparatus for reducing intermodulation distortion is disclosed. In one embodiment, the method comprises the steps of accepting a sampled input signal V(t) wherein the input signal V(t) comprises a plurality of peaks; determining n peaks V,V, . . . Vof the sampled input signal V(t) exceeding a clip value Vat times t, t, . . . t; and modifying the sampled input signal V(t) by weighting the n peaks V,V, . . . ,Vexceeding the clip value Vof the sampled input signal V(t) by a function b(t) wherein b(t) is either a hard limiting function or b(t)=f(a, a, . . . a;t−t,t−t, . . . t−t), wherein a,a, . . . aare weight values corresponding to the n peaks V, V, . . . V, and f(t−t,t−t, . . . t−t) is a smooth shaping function. Intermodulation performance is then selectively improved in selected sub-bands by notch filtering prior to application to the non-linearity.