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:
Feb. 26, 2008
Filed:
Jun. 25, 2002
Tommi Auranen, Turku, FI;
Juha Kajava, Naantali, FI;
Tommi Auranen, Turku, FI;
Juha Kajava, Naantali, FI;
Nokia Corporation, Espoo, FI;
Abstract
The invention relates to a method for correcting an IQ-imbalance (In-phase and Quadrature) of an IQ-based direct conversion receiver (). In the method a group of radio frequency pilot signals are received in the direct conversion receiver (). They are conveyed to an in-phase branch and a quadrature-phase branch of the receiver () and mixed, in the analogue domain, to form a baseband in-phase (I) and quadrature-phase (Q) signal components. The signal componets are conveyed to a digital demodulator () which detects the IQ-phase imbalance of the direct conversion receiver () by analysing at least one of the baseband in-phase (I) and the quadrature-phase (Q) signal components. In the method, the detected IQ-imbalance is corrected, in the analogue domain of the direct conversion receiver (), to achieve a 90 degrees phase difference between a future baseband in-phase (I) signal component and a future baseband quadrature-phase (Q) signal component.