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:
Apr. 09, 2013
Filed:
Oct. 13, 2005
Aiguo Yan, North Andover, MA (US);
Ayman Shabra, Woburn, MA (US);
Aiguo Yan, North Andover, MA (US);
Ayman Shabra, Woburn, MA (US);
MediaTek Inc., Hsin-Chu, TW;
Abstract
The invention relates to a cascaded scheme in which an RRC filter, a modified RRC filter or other digital filter is implemented at a relatively low data rate, such as twice the symbol or chip rate, or 2×. Interpolation filters are used to increase the data rate to a higher data rate, such as 8×. Decimation filters are used to reduce the data rate from a higher rate, such as 8×, to a lower rate, such as 2×. The coefficients of the digital filter may be adjusted to compensate for characteristics of other components across the entire filter chain. Most of the implementation complexity of the filter chain is consolidated into the relatively low rate (such as 2×) digital filter while interpolation or decimation filters can be implemented at very low cost. The compensation capability provided by the digital filter makes design of simple decimation or interpolation filters much easier. The compensation capability provided by the digital filter, along with the relatively high over-sampling rate for the output of the interpolation filter (or the input of the decimation filter), also makes the design of the preceding (or following) analog filters much easier.