Nxp B.v.

Koninklijke Philips Corporation N.v.

U.S. Philips Corporation

St-ericsson Sa

Gerben Willem De Jong

Johannes Hubertus Antonius Brekelmans

Johannes O Voorman

Mark Pieter Van Der Heijden

Jozef Reinerus Maria Bergervoet

Dennis Jeurissen

Jan Van Sinderen

Jan Sophia Vromans

Gian Hoogzaad

Xin Yang

Rachid El Waffaoui

Joao N V L Ramalho

Eric Pieraerts

Josephus Arnoldus Henricus Maria Kahlman

Tony Vanhoucke

Dominicus Martinus Wilhelmus Leenaerts

Hugo Veenstra

Giuseppe Grillo

Manel Collados Asensio

Edwin Van Der Heijden

Mihai A T Sanduleanu

Johannes H A Brekelmans

Marcellinus Johannes Maria Geurts

Luan Le

Paulus T M Van Zeijl

Jozef A M Ramaekers

Jan C A Dekkers

Simon W K Lee

Joao Nuno Vila Lobos Ramalho

Ivan Matkov Zahariev

An RF power amplifier is described including a first amplifier and a second amplifier arranged in parallel between an RF power amplifier input and an RF power amplifier output. A phase adjuster adjusts the phase of a signal on at least one of the first amplifier signal path and the second amplifier signal path. A first impedance inverter has a first impedance inverter input coupled to an output of the second amplifier and a first impedance inverter output coupled to the RF power amplifier output. The RF power amplifier is configured to enable at least one of the first amplifier and the second amplifier dependent on an operation mode and the first impedance inverter is configured to modulate the load impedance of the second amplifier in response to the operation mode changing.

Radio-frequency amplifier

Switch arrangement

A bias circuit for a bipolar RF amplifier is described. The bias circuit includes a current source coupled to a bias network. The bias network supplies a base current to the transistors in the amplifier circuit of the bipolar RF amplifier. The bias circuit includes a buffer coupled to the bias network and to the bipolar RF amplifier. The buffer provides additional base current to the amplifier circuit of bipolar RF amplifier and sinks avalanche current generated by the amplifier circuit of the bipolar RF amplifier.

Bias circuit

A biased-transistor-module comprising: a module-input-terminal; a module-output-terminal; a reference-terminal; a module-supply-terminal configured to receive a supply voltage; a module-reference-voltage-terminal configured to receive a module reference voltage; a main-transistor having a main-control-terminal, a main-first-conduction-channel-terminal and a main-second-conduction-channel-terminal, wherein the main-first-conduction-channel-terminal is connected to the module-output-terminal, and the main-second-conduction-channel-terminal is connected to the reference-terminal, and the main-control-terminal is connected to an input-signal-node, wherein the input-signal-node is connected to the module-input-terminal; and a bias-circuit. The bias-circuit comprises: a first-bias-transistor; a first-bias-resistor; a second-bias-transistor; and a second-bias-resistor.

Biased transistor module

A Doherty amplifier circuit comprising: a splitter having: a splitter-input-terminal for receiving an input signal; a main-splitter-output-terminal; and a peaking-splitter-output-terminal; a main-power-amplifier having a main-power-input-terminal and a main-power-output-terminal, wherein; the main-power-input-terminal is connected to the main-splitter-output-terminal; and the main-power-output-terminal is configured to provide a main-power-amplifier-output-signal; a peaking-power-amplifier having a peaking-power-input-terminal and a peaking-power-output-terminal, wherein: the peaking-power-input-terminal is connected to the peaking-splitter-output-terminal; and the peaking-power-output-terminal is configured to provide a peaking-power-amplifier-output-signal. The splitter, the main-power-amplifier and the peaking-power-amplifier are provided by means of an integrated circuit.

Doherty amplifier circuits

A down-converter for receiving a multiband radio frequency signal (RF) and a local oscillator signal comprises a frequency divider and a heterodyne receive chain. The frequency divider is configured to divide the local oscillator signal and provide different divided local oscillator signals. The heterodyne receive chain comprises a first stage mixer and second stage mixers. The first stage mixer is configured to mix the multiband radio frequency signal and either the local oscillator signal or a divided local oscillator signal to generate a first intermediate frequency signal. Each second stage mixer is configured to mix the first intermediate signal and a divided local oscillator signal to generate second intermediate frequency signals that each represent a band from the multiband radio frequency signal. The frequency divider is configured to provide a different divided local oscillator signal to each of the second stage mixers.

Down-converter

The invention concerns in general measurement of the transfer function of linear time invariant systems, more particular the calibration of such systems based on a measured transfer function. According to a first aspect the present invention an arrangement for measuring the transfer function of a linear time-invariant system is disclosed. According to a second aspect of the present invention the arrangement is implemented into a linear time-invariant circuitry having a transfer function representing the amplitude and phase characteristic of the circuitry, where by means of the arrangement for measuring the transfer function the transfer function can be optimized in accordance with certain criteria on-the-fly, i.e. in or before operation of the circuit. Finally, an effective and simple method for measuring of the transfer function of a linear time-invariant system together with the use or application of the method is shown.

Calibration of linear time-invariant system's step response

The present invention relates to a circuit arrangement () for generating non-overlapping and immune-to-1/f-noise signals as has been described. A break-before-make (BBM) circuit ensures that the differential I/Q signals (LO, LO, LO, LO), driving the transistors (M, M, M, M) of mixers (A,B) in an RF receiver (), are non-over-lapping for having at any time only one of these transistors turned on. The duty cycle of each driving signal is measured, and the difference (&#x394;) in the duty cycle corresponding to two subsequent LO phases is determined through a respective differential amplifier (A-D). Each differential amplifier is configured to have a current output (LT, LT, LT, LT), which is then fed back to the input of the input buffer (A-D) corresponding to the first LO phase in order to adjust its logic threshold (LT) level and make the difference (&#x394;) equal to zero. Thereby, the combined action of the BBM circuit and the feedback loops results in four non-overlapping differential I/Q signals (LO, LO, LO, LO) with constant and mutually equal duty cycles, and fixed and well-defined relative positions.

Low-1/F-noise local oscillator for non-overlapping differential I/Q signals

An electronic device comprising a passive harmonic-rejection mixer () and a calibration circuitry (). The passive harmonic rejection mixer has an input () connected to several sub-mixer stages (), and the sub-mixer stages are connected to a summing module () for generating the output (). Each sub-mixing stage comprises a gating module (), an amplifier (), and a weighting module (), the gating module selectively passing the input signal or the input signal with inverted polarity under the control of control signals. The calibration circuitry () is adapted to input a reference signal () to the input of the mixer, receive an output signal () from the output of the mixer, and set the weights (K, K, K, K) of the weighting modules to make the output signal match an expected output signal.

Calibration of passive harmonic-rejection mixer

A frequency conversion circuit configured to mix a first input signal (RF+,RF&#x2212;) at a first frequency with a second input signal (LO+,LO&#x2212;) at a second frequency to provide an output intermediate frequency signal (IF), the circuit comprising: first and second mixing modules, each mixing module comprising a voltage to current converter configured to receive the first input signal (RF+,RF&#x2212;) and connected to a Gilbert mixer configured to receive the second input signal (LO+,LO&#x2212;); an intermediate frequency output circuit having inputs connected to receive an intermediate frequency current signal (IF+,IF&#x2212;) from outputs of each of the Gilbert mixers and an output configured to provide the output intermediate frequency voltage signal (IF), wherein the first and second mixing modules comprise transistors which are complementary to each other.

Frequency conversion

An electronic device comprising a passive harmonic-rejection mixer. The passive harmonic rejection mixer has an input connected to several sub-mixer stages, and the sub-mixer stages are connected to a summing module for generating the output. Each sub-mixing stage comprises a gating module and a respective amplifier, the gating module adapted to selectively pass the input signal or the input signal with inverted polarity under the control of control signals.

Passive harmonic-rejection mixer

A system and method for Cartesian modulation achieved via generation of a three-level pulse width modulated signal. The system in overview comprises two binary pulse width modulated signal generators receiving signals related to the in-phase and quadrature components of a base-band signal and a combination and amplification stage that combines the signals provided by the two binary pulse width modulated signal generators. The binary pulse width modulated signal generators contain at least one signal comparator and at least one base-band pre-distortion element. The signals related to the in-phase and quadrature components of the base-band signal may be; the positive or negative parts of the in-phase component, the positive or negative parts of the quadrature component, the absolute value or sign of the in-phase component, or the absolute value or sign of the quadrature component. These signals may be distorted by a base-band pre-distortion element before being coupled to the comparators.

Cartesian modulation system via multi-level pulse width modulation

The present invention relates to a circuit arrangement and method of applying predistortion to a baseband signal used for modulating a pulse-shaped signal, wherein an envelope information of the baseband signal is detected and slewing distortions of the pulse-shaped signal are reduced by applying at least one of a phase modulation and a duty cycle 5 modulation to the baseband signal as additional predistortion in response to the detected envelope information. Thereby, slewing distortions in the pulse-shaped signal are removed or at least reduced.

Enhanced predistortion for slewing correction

The present invention relates in general to transferring the envelope information of a polar modulated signal to a varying pulsewidth signal, while the phase modulation is direct transferred to the phase modulation of this PWM signal. Accordingly, the resultant signal is a PWM-PPM-signal. Such a signal can efficiently amplified by use of switching amplifying stages. By the present invention four pre-distorted baseband signals are applied basically to 4 linear RF mixers and a two adders, which are, the only needed external RF building blocks to build the modulator according to the invention. That is, the basic idea of the invention resides in the way of modulation of the four baseband signals and the way of combining of the RF modulated signals.

Radio frequency PWM & PPM modulator

A receiver () is arranged to simultaneously receive at least a first (S) radio frequency signal having a first frequency band () and a second radio frequency signal (S) having a second frequency band () that is at least partly overlapping the first frequency band (). The receiver has frequency down-conversion means () for frequency down converting the at least first (S) and second radio frequency signals (S) to at least a first (S) and a second (S) lower frequency signal and multiplexing means () for sequentially multiplexing the at least first (S) and second lower frequency signals (S) into a frequency multiplexed signal (S).

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Eindhoven, Netherlands

Gerben Willem De Jong