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. 08, 2014
Filed:
Aug. 20, 2010
Jianhua Chen, Shenzhen, CN;
Hong Yi, Shenzhen, CN;
Jianhua Chen, Shenzhen, CN;
Hong Yi, Shenzhen, CN;
ZTE Corporation, Shenzhen, Guangdong Province, CN;
Abstract
Method and apparatus for controlling bias point of DQPSK demodulator are disclosed. The method comprises: step 1: respectively applying first and second bias voltages to I-path and Q-path, and applying identical pilot voltage signals to I-path and Q-path (S); step 2: executing filtering processing on I-path and Q-path differential current signals collected by balance receiver and determining θand θ(S); step 3: performing feedback control to first and second bias voltages respectively according to θand θso that θand θrespectively reaches expected bias point values of I-path and Q-path (S); executing step 2 and 3 cyclically at preset regular intervals (S), so that θand θremains consistently the expected bias point values of I-path and Q-path. The solution enables bias point of DQPSK demodulator to be locked at any expected bias point value, facilitates realization of digitization, and is not easily influenced.