Abstract: An analog amplitude pre-distortion circuit and method. The circuit includes an RF input for receiving an RF signal. The circuit also includes an amplifier stage comprising an amplifier stage input coupled to the RF input, wherein the amplifier stage is operable to amplify the RF signal to produce an amplified RF signal. The circuit further includes a bias circuit. The bias circuit includes a transistor having a first current terminal, a second current terminal and a control terminal, wherein the first current terminal is coupled to the amplifier stage input and wherein the second current terminal is coupled to a reference potential. The bias circuit also includes a resistor coupled between the amplifier stage input and the control terminal. The bias circuit also includes a variable reactance component coupled to the control terminal. The bias circuit further includes a capacitor coupled between the control terminal and the reference potential.

Abstract: An analog amplitude pre-distortion circuit and method. The circuit includes a Radio Frequency, RF, input for receiving an RF signal. The circuit also includes an amplifier stage comprising an amplifier stage input for receiving the RF signal from the RF input, wherein the amplifier stage is operable to amplify the RF signal to produce an amplified RF signal. The circuit further includes a bias circuit. The bias circuit includes a detector stage for detecting an amplitude of the RF signal, and for producing a correction signal based on the amplitude of the RF signal. The bias circuit also includes a bias application stage coupled to the amplifier stage input.

Abstract: A circuit comprising: an input terminal; a first amplifier coupled to the input terminal of the circuit to receive an input signal; a first inductor having a first terminal coupled to the input terminal and a second terminal configured to be coupled to the ground terminal, wherein the first inductor is arranged with a second inductor and configured to magnetically couple therewith, wherein said second inductor is coupled to the first amplifier and is configured to sense a current through the amplifier.

Abstract: 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.

Abstract: 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.

Abstract: A switch arrangement comprising: a transceiver node coupled to a first and second circuit branch, the first circuit branch including a transmit node, the second circuit branch including a receive node; wherein the first circuit branch comprises an inductor coupled in series and a first semiconductor switch, in parallel, configured to provide a switched coupling to a reference voltage; and wherein the second circuit branch comprises one of: i) a second and third semiconductor switch; and ii) a second semiconductor switch and a third semiconductor switch configured to control the application of a supply voltage to an amplifier; and iii) a further semiconductor switch configured to control the application of a bias current to an amplifier; wherein in the first switch mode, impedance matching between the transceiver node and transmit node is provided; in the second switch mode, impedance matching between the transceiver node and receive node is provided.

Abstract: A switch arrangement comprising: a transceiver node coupled to a first and second circuit branch, the first circuit branch including a transmit node, the second circuit branch including a receive node; wherein the first circuit branch comprises an inductor coupled in series and a first semiconductor switch, in parallel, configured to provide a switched coupling to a reference voltage; and wherein the second circuit branch comprises one of: i) a second and third semiconductor switch; and ii) a second semiconductor switch and a third semiconductor switch configured to control the application of a supply voltage to an amplifier; and iii) a further semiconductor switch configured to control the application of a bias current to an amplifier; wherein in the first switch mode, impedance matching between the transceiver node and transmit node is provided; in the second switch mode, impedance matching between the transceiver node and receive node is provided,

Abstract: 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.

Abstract: 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.

Abstract: A pressure sensor device having a chamber filled with a pressure transfer medium, the chamber having at least one window that at least partly transfers pressure waves in a fluid; an optical fiber extending longitudinally through the chamber, the optical fiber including a Fiber Bragg Grating and two mounting spots at opposite sides of the Fiber Bragg Grating; a frame having a first frame end and a longitudinally opposite second frame end; a pressure response assembly connected in parallel to a fiber portion between the two mounting spots, the pressure response assembly including a series arrangement of a pressure response element and a movement damper; and a resilient member connected in series to the frame and to a parallel arrangement of the fiber portion and the pressure response assembly.

Abstract: The thickness of an at least partially transparent layer is measured using wavelength band limited light, with a coherence length that is less than twice the thickness of the layer. Reflections from layer are fed to a 2-n coupler (n>2) via optical transmission paths of different optical length. The 2-n coupler mix light from the path into n combinations of light from the paths, each combination with a different mutual phase offset between the light from the two paths. This leads to coherent interference between reflections from the front and back of the layer when the difference between the optical lengths of the optical transmission paths compensates for the path between reflection from the front and the back. A processing circuit computes information indicative of a phase difference between the reflections from n intensities of the 2-n coupler. The use of n>2 signals makes it possible to eliminate the influence of reflection amplitude variations on the computed phase difference.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A pressure sensor device having a chamber filled with a pressure transfer medium, the chamber having at least one window that at least partly transfers pressure waves in a fluid; an optical fiber extending longitudinally through the chamber, the optical fiber including a Fiber Bragg Grating and two mounting spots at opposite sides of the Fiber Bragg Grating; a frame having a first frame end and a longitudinally opposite second frame end; a pressure response assembly connected in parallel to a fiber portion between the two mounting spots, the pressure response assembly including a series arrangement of a pressure response means and a movement damper; and a resilient member connected in series to the fiber portion and the frame.

Abstract: 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.

Abstract: 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.

Abstract: An electronic device comprising a passive harmonic-rejection mixer (400) and a calibration circuitry (425). The passive harmonic rejection mixer has an input (102) connected to several sub-mixer stages (402), and the sub-mixer stages are connected to a summing module (406, 408) for generating the output (104). Each sub-mixing stage comprises a gating module (414), an amplifier (416), and a weighting module (418), the gating module selectively passing the input signal or the input signal with inverted polarity under the control of control signals. The calibration circuitry (425) is adapted to input a reference signal (430) to the input of the mixer, receive an output signal (104) from the output of the mixer, and set the weights (K1, K2, K3, K4) of the weighting modules to make the output signal match an expected output signal.

Abstract: 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.