Abstract: The invention relates to a device for digital-to-radio frequency conversion, the device comprising: conversion cell matrices for digital-to-radio frequency conversion; means for providing a digital data signal; means for dividing the digital data signal into data signal groups; means for generating clock signals, the clock signals having different phases, the number of clock signals being the same as the number of data signal groups; means for synchronizing the data signal groups by using the clock signals; means for conveying the synchronized data signal groups to the conversion cell matrices, the number of conversion cell matrices being the same as the number of data signal groups; and means for synchronizing each conversion cell matrix by using the clock signal with which the synchronized data signal group conveyed thereto was synchronized for generating interpolation values.

Abstract: The invention describes a method for digitally calibrating a segmented current-steering D/A-converter. One embodiment of the present invention is a 14-bit DAC, where 6 MSB's are converted with two unweighted current source array. Further, in this invention a new method for organising the switching order based on the analysed data of mismatch of the current sources is presented. A programmable mapping device is used instead of the fixed thermometer decoding before the switch array. Using this programmable mapping device the switching order of the current switches can be selected optimally so that the error in the resulting analog signal is minimised. The switching order is programmed to the mapping device on the basis of the calibration method according to the present invention. The inventive amendment is aimed at processing errors which cause poor matching inside the component itself. This amendment is done by rearranging unweighted unity current switches into a more optimum order.

Abstract: The invention describes a method for digitally calibrating a segmented current-steering D/A-converter. One embodiment of the present invention is a 14-bit DAC, where 6 MSB's are converted with two unweighted current source array. Further, in this invention a new method for organising the switching order based on the analysed data of mismatch of the current sources is presented. A programmable mapping device is used instead of the fixed thermometer decoding before the switch array. Using this programmable mapping device the switching order of the current switches can be selected optimally so that the error in the resulting analog signal is minimised. The switching order is programmed to the mapping device on the basis of the calibration method according to the present invention. The inventive amendment is aimed at processing errors which cause poor matching inside the component itself. This amendment is done by rearranging unweighted unity current switches into a more optimum order.

Abstract: An 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 and Q data parts to be converted by the conversion modules 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 D/A conversion function and upconversion function 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-switch pair. LO-switch is further connected in series to a current source.

Abstract: A polar transmitter, operable in linear mode or switched mode, uses a conversion module to convert baseband signals into amplitude data and phase data. The phase data is used to phase modulate a carrier frequency in a RF conversion module. The module comprises a plurality of parallel unit cells, each being a mixer cell type converter having a differential data switch section connected in series to a differential LO-switch pair. The differential LO-switch is connected in series to a current source. Each unit cell is adapted to receive a signal through an input end. In switched mode, the phase-modulated carrier frequency is amplitude modulated by the amplitude data through the supply voltage to a power amplifier. In linear mode, amplitude data is conveyed to the input end of the unit cells for modulating the phase-modulated carrier frequency in the conversion module.

Abstract: A digital to RF-conversion device that combines the D/A conversion function and the upconversion function by a RF-carrier or IF-signal. The device comprises a plurality of parallel unit cells, each of which is a mixer cell type converter having a differential data switch section connected in series to a differential LO-switch pair. The differential LO-switch is further connected in series to a current source. Each unit cell is adapted to receive a control voltage indicative of a data signal value.

Abstract: A digital to RF-conversion device that combines the D/A conversion function and the upconversion function by a RF-carrier or IF-signal. The device comprises a plurality of parallel unit cells, each of which is a mixer cell type converter having a differential data switch section connected in series to a differential LO-switch pair. The differential LO-switch is further connected in series to a current source. Each unit cell is adapted to receive a control voltage indicative of a data signal value.

Abstract: An RF transmitter having two digital to RF-conversion devices that combine the D/A conversion function and the upconversion function by a RF-carrier or IF-signal. The device comprises a plurality of parallel unit cells, each of which is a mixer cell type converter having a differential data switch section connected in series to a differential LO-switch pair. The differential LO-switch is further connected in series to a current source. Each unit cell is adapted to receive a control voltage indicative of a data signal value.

Abstract: The invention describes a method for digitally calibrating a segmented current-steering D/A-converter. One embodiment of the present invention is a 14-bit DAC, where 6 MSB's are converted with two unweighted current source array. Further, in this invention a new method for organising the switching order based on the analysed data of mismatch of the current sources is presented. A programmable mapping device is used instead of the fixed thermometer decoding before the switch array. Using this programmable mapping device the switching order of the current switches can be selected optimally so that the error in the resulting analog signal is minimised. The switching order is programmed to the mapping device on the basis of the calibration method according to the present invention. The inventive amendment is aimed at processing errors which cause poor matching inside the component itself. This amendment is done by rearranging unweighted unity current switches into a more optimum order.

Abstract: The invention relates to a digital-to-analog converter. In order to reduce distortion in the output, the converter comprises a first and a second current output (OUT, XOUT), at least two current sources (1) and assigned to each of the current sources (1) a current switch circuit. Each current switch circuit comprises means (4, 5, 6, 7) for creating two overlapping complementary control signals out of a signal indicating whether the current source (1) is selected, while in a first group of the current switch circuits the connection of the current source (1) to the current outputs is controlled by one of the control signals respectively, and while in a second group of the current switch circuits the control by the control signals is exchanged, each of the current switch circuits of the second group comprising in addition means (10) for inverting the signal input to the means for creating two overlapping complementary control signal (4, 5, 6, 7).

Abstract: The invention relates to a digital-to-analog converter. In order to reduce distortion in the output, the converter comprises a first and a second current output (OUT, XOUT), at least two current sources (1) and assigned to each of the current sources (1) a current switch circuit. Each current switch circuit comprises means (4, 5, 6, 7) for creating two overlapping complementary control signals out of a signal indicating whether the current source (1) is selected, while in a first group of the current switch circuits the connection of the current source (1) to the current outputs is controlled by one of the control signals respectively, and while in a second group of the current switch circuits the control by the control signals is exchanged, each of the current switch circuits of the second group comprising in addition means (10) for inverting the signal input to the means for creating two overlapping complementary control signal (4, 5, 6, 7).