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:
Sep. 02, 2008
Filed:
Apr. 29, 2005
Niall Eric Shakeshaft, Helsinki, FI;
Jussi Heikki Vepsäläinen, Helsinki, FI;
Petri Tapani Eloranta, Espoo, FI;
Pauli Mikael Seppinen, Espoo, FI;
Niall Eric Shakeshaft, Helsinki, FI;
Jussi Heikki Vepsäläinen, Helsinki, FI;
Petri Tapani Eloranta, Espoo, FI;
Pauli Mikael Seppinen, Espoo, FI;
Nokia Corporation, Espoo, FI;
Abstract
A radio frequency (RF) transmitter uses two digital-to-RF conversion modules to convert digital baseband signals into RF signals. In cartesian mode, baseband signals are conveyed to the conversion modules for RF conversion. In polar mode, baseband signals are converted into amplitude and phase data parts. Phase data part is converted into I (inphase) and Q (quadrature) data parts to be converted into RF signals which are modulated in a power amplifier by amplitude data part through the power supply of the power amplifier. Each digital-to-RF module uses parallel unit cells to perform digital-to-analog (D/A) conversion and upconversion functions by an IF signal. Each unit cell, adapted to receive a control voltage indicative of a data signal value, is a mixer cell type converter having a differential data switch section connected in series to a differential LO (local oscillator)-switch pair. LO-switch is further connected in series to a current source.