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:
Dec. 18, 2007
Filed:
Oct. 27, 2003
Julius Koskela, Helsinki, FI;
Jouko Lokio, Espoo, FI;
Hans-otto Scheck, Espoo, FI;
Nokia Corporation, Espoo, FI;
Abstract
A direct conversion receiver includes a receiver for receiving a signal including multiple components at different receiving frequencies belonging to a frequency band. A mixer mixes the signal components into a base band signal comprising I- and Q branches. A converter converts the analog base band signal into a digital signal. The receiver includes a measuring unit for measuring power levels of the signal components in pairs, where one component in the pair belongs to an upper sideband of the frequency band and one component in the pair belongs to a lower sideband of the frequency band. An estimator estimates, when either the upper sideband component or the lower sideband component dominates in power over the component in the pair, a frequency-independent phase imbalance, a frequency-dependent phase imbalance and a gain imbalance, and a compensator compensates the estimated imbalances to at least one of the I- and Q-branch signals.