Abstract: Calibration data for calibrating time to digital conversion is obtained by switching a feed circuit of a time to digital converter between a normal operating mode or a calibration mode. A delay circuit with a delay circuit input and a plurality of taps outputs. A sampling register samples data from the data inputs. The feed circuit provides for selection of transitions of the oscillator signal that control timing of a first active transition at the clock circuit after a transition at the delay circuit input. A control circuit switches the feed circuit between normal operating mode and calibration mode, and controls the feed circuit successively to select a plurality of different transitions to control timing of the first active transition in the calibration mode. The control circuit reads out resulting data from the sampling register for each selection and determines calibration data for the oscillator signal from said data.

Abstract: An output stage (1) for a digital RF transmitter is provided. The output stage comprises: an input adapted to receive an input signal (RFin, b7-b0) to be transmitted; a plurality N of power amplification sections (S1, S2, S3, S4); and an output (A, B) providing an output voltage signal. Each of the N power amplification sections (S1, S2, S3, S4) is arranged to receive the input signal (RFin, b7-b0) and comprises a transformer (T1, T2, T3, T4) adapted to provide a respective output signal. Each transformer comprises a primary stage and a secondary stage; the secondary stages of the transformers (T1, T2, T3, T4) of the N power amplification sections (S1, S2, S3, S4) are combined such that a combined output voltage signal of the output stage is provided. The N power amplification sections (S1, S2, S3, S4) are adapted such that the input signal (RFin, b7-b0) is latched by clock signals (clock1, clock2, clock3, clock4) comprising different phases.

Abstract: Modulators for amplitude-modulating signals defined by phase information and envelope codes are provided with first transistors for receiving the phase information and second transistors for receiving the envelope codes. The first main electrode of one transistor is coupled to the second main electrode of the other transistor and the other second main electrode constitutes an output of the modulator. This modulator can be used in any kind of transistor environment and is simple and low cost. The doped areas of the coupled first and second main electrodes comprise an overlap to reduce cross-talk and to reduce silicon area. Polar transmitters are provided with this modulator and with a circuit for generating a phase/frequency code and the envelope code and with an oscillator for receiving the phase/frequency code and for generating the phase information. A phase shift between the phase information and the envelope code reduce aliases.

Abstract: Calibration data for calibrating time to digital conversion is obtained by switching a feed circuit (20) of a time to digital converter between a normal operating mode or a calibration mode. A delay circuit (22) with a delay circuit input and a plurality of taps outputs respective, differently delayed versions of a signal from a delay circuit input. A sampling register (24) has data inputs coupled to the taps, and samples data from the data inputs in response to an active transition at a clock input. When in the normal operating mode, the feed circuit (2) feeds an oscillator signal of an oscillator circuit (10) to the delay circuit input and a reference signal to the clock input of the sampling register (24). When in the calibration mode, the feed circuit (20) supplies signals with transitions having timing controlled by the oscillator signal to both the delay circuit input and the clock input.

Abstract: The present invention relates to a polar transmission method and a polar transmitter for transmitting phase and amplitude components derived from in-phase (I) and quadrature-phase (Q) components of an input signal. A first conversion is provided for converting the in-phase (I) and quadrature-phase (Q) components into the phase and amplitude components at a first sampling rate. Additionally, a second conversion is provided for converting the phase component into a frequency component, wherein the second conversion comprises a rate conversion for converting the first sampling rate into a lower second sampling rate at which the frequency component is provided. Thereby, the second sampling rate can be used as a lower update rate in a digitally controlled oscillator in order to save power or because of speed limitations, while the surplus phase samples obtain due to the higher first sampling rate enable better approximation of the phase component after the digitally controlled oscillator.

Abstract: The present invention relates to a transmission apparatus having at least two transmission branches for transmitting respective transmission signals at substantially same frequencies, and to a method of controlling such a transmission apparatus. A first oscillator circuit (62) is provided for generating a first signal at a first frequency to be used in a first transmission branch. Additionally, a second oscillator circuit (64) is provided for generating a second signal at a second frequency to be used in a second transmission branch, the second frequency being different from the first frequency. To enable transmission of the transmission signals at said substantially same frequencies, at least one frequency divider or multiplier (72, 74) is provided for dividing or respectively multiplying at least one of said first and second frequencies by a respective predetermined factor. Thereby, the first and second oscillator circuits can be operated at different frequencies, so that mutual coupling can be reduced.

Abstract: An output stage (1) for a digital RF transmitter is provided. The output stage comprises: an input adapted to receive an input signal (RFin, b7-b0) to be transmitted; a plurality N of power amplification sections (S1, S2, S3, S4); and an output (A, B) providing an output voltage signal. Each of the N power amplification sections (S1, S2, S3, S4) is arranged to receive the input signal (RFin, b7-b0) and comprises a transformer (T1, T2, T3, T4) adapted to provide a respective output signal. Each transformer comprises a primary stage and a secondary stage; the secondary stages of the transformers (T1, T2, T3, T4) of the N power amplification sections (S1, S2, S3, S4) are combined such that a combined output voltage signal of the output stage is provided. The N power amplification sections (S1, S2, S3, S4) are adapted such that the input signal (RFin, b7-b0) is latched by clock signals (clock1, clock2, clock3, clock4) comprising different phases.

Abstract: The present invention relates to a polar transmission method and a polar transmitter for transmitting phase and amplitude components derived from in-phase (I) and quadrature-phase (Q) components of an input signal. A first conversion is provided for converting the in-phase (I) and quadrature-phase (Q) components into the phase and amplitude components at a first sampling rate. Additionally, a second conversion is provided for converting the phase component into a frequency component, wherein the second conversion comprises a rate conversion for converting the first sampling rate into a lower second sampling rate at which the frequency component is provided. Thereby, the second sampling rate can be used as a lower update rate in a digitally controlled oscillator in order to save power or because of speed limitations, while the surplus phase samples obtain due to the higher first sampling rate enable better approximation of the phase component after the digitally controlled oscillator.

Abstract: A high efficiency modulating RF amplifier (10) for amplitude modulating a signal defined by a phase information signal (1) and an envelope signal (2) comprises a power supply (30) arranged to provide an operating voltage under control of the envelope signal (2). The power supply (30) comprises a plurality of power supply stages (40) and a plurality of supply switches (50) coupled between the plurality of power supply stages (40) and the modulator (20). The power supply (30) is arranged to select one of the power supply stages (40) to provide the operating voltage under control of the envelope signal (2). The high efficiency modulator RF amplifier further comprises a modulator (20) for receiving the phase information signal (1), the envelope signal (2) and the operating voltage. The modulator (20) is arranged to provide an output signal of which an amplitude is modulated under control of the envelope signal (2).

Abstract: A receiver (10) is arranged to simultaneously receive at least a first (S1) radio frequency signal having a first frequency band (1) and a second radio frequency signal (S3) having a second frequency band (3) that is at least partly overlapping the first frequency band (1). The receiver has frequency down-conversion means (32,33) for frequency down converting the at least first (S1) and second radio frequency signals (S3) to at least a first (S2) and a second (S4) lower frequency signal and multiplexing means (34) for sequentially multiplexing the at least first (S2) and second lower frequency signals (S4) into a frequency multiplexed signal (S5).

Abstract: The present invention relates to a polar signal generator and method of deriving phase and amplitude components from in-phase (I) and quadrature-phase (Q) components of an input signal, wherein the I and Q components are generated at a first sampling frequency based on the input signal, and are then up-sampled in accordance with a predetermined first interpolation factor (N), to generate up-sampled I and Q components at a second sampling frequency higher than the first sampling frequency. The up-sampled I and Q components are converted into the phase and amplitude components, wherein the converting step is operated at the second sampling frequency. Moreover, the phase and amplitude components can be further up-sampled, optionally by different sampling frequencies, to a third and a fourth sampling frequency. Thereby, I-Q generation and cartesian-to-polar transformation can be performed at lower frequencies, which reduces power consumption.

Abstract: A receiver (10) is arranged to simultaneously receive at least a first (S1) radio frequency signal having a first frequency band (1) and a second radio frequency signal (S3) having a second frequency band (3) that is at least partly overlapping the first frequency band (1). The receiver has frequency down-conversion means (32,33) for frequency down converting the at least first (S1) and second radio frequency signals (S3) to at least a first (S2) and a second (S4) lower frequency signal and multiplexing means (34) for sequentially multiplexing the at least first (S2) and second lower frequency signals (S4) into a frequency multiplexed signal (S5).