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. 17, 2012
Filed:
Dec. 01, 2008
Paul Murray Row, Bishops Stortford, GB;
Dorian Thomas Charles Davies, Bishops Stortford, GB;
Paul Murray Row, Bishops Stortford, GB;
Dorian Thomas Charles Davies, Bishops Stortford, GB;
Rockstar Bidco LP, New York, NY (US);
Abstract
Embodiments of the invention are concerned with correction of quadrature errors associated with digital communications systems, and in particular in a wireless transmit chain in which an up-converter and a down-converter both have a direct conversion architecture. One embodiment comprises a correction network for correcting a difference between a transmission characteristic of an in-phase signal path and a transmission characteristic of a quadrature signal path, said quadrature signal path being for the transmission of in-phase and quadrature parts of a signal and the signal comprising frequency components within a base band, wherein the correction network comprises an in-phase input port, a quadrature input port, an in-phase output port and a quadrature output port, wherein each input port is connected to each output port by a digital filter network, the digital filter network comprising a set of filter tap coefficients and configuration means for configuring values of said set of filter tap coefficients. Since each input port is connected to each output port by a digital filter network comprising a set of filter tap coefficients and having configuration means for configuring values of said set of filter tap coefficients, frequency dependent quadrature impairments, for example due to the analogue components of a quadrature up-converter or down-converter, may be corrected by suitable control of the coefficients.