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:
Jan. 31, 2006
Filed:
Dec. 03, 2002
Che-sheng Chiu, Taoyuan, TW;
Kai-an Tang, Taoyuan, TW;
Su-chin Hsieh, Taoyuan, TW;
Chiung-jang Chen, Taoyuan, TW;
Che-Sheng Chiu, Taoyuan, TW;
Kai-An Tang, Taoyuan, TW;
Su-Chin Hsieh, Taoyuan, TW;
Chiung-Jang Chen, Taoyuan, TW;
Chunghwa Telecom Co., Ltd., Taoyuan, TW;
Abstract
The present invention discloses a method for finding an optimized filter parameters design to meet input specifications and hardware constraints in accordance with a typical single channel digital IF programmable downconverter. Said typical single channel digital IF programmable downconverter comprises four stages, including a high speed down-sampling stage, a spectral shaping stage, a rate matching stage and an oversampling stage. According to input specifications, said method firstly determines a number of Halfband interpolation filters used in said oversampling stage, secondly obtains optimized parameters for a CIC decimation filter and a Halfband decimation filter in said high speed down-sampling stage, using as many Halfband decimation filters as possible. Then determine if it is necessary to use re-sampling FIR filter for rate matching. Finally, use various function window to design programmable FIR filter for spectral shaping, obtains an overall synthesized spectral response which meets input specifications.