In an embodiment an integration circuit has a first input terminal configured to receive a first input signal, a second input terminal configured to receive a second input signal, an output terminal to provide an output signal as a function of the first and the second input signal, a first and a second amplifier, each being switchably connected between the first or the second input terminal and the output terminal, and a capacitor which is switchably coupled in a feedback loop either of the first or of the second amplifier such that the capacitor and one of the first and the second amplifier form an inverting integrator providing the output signal. Therein the integration circuit is prepared to be operated in a first and a second subphase, wherein in each of first and second subphases one of the first and the second input signals is supplied to the inverting integrator and the respective other one of first and the second input signals is supplied to the respective other one of the first and the second amplifier.

Included are: a first power source 3 configured to output a voltage required for a first gate bias voltage for turning a power amplifier 2 to an ON state; a second power source 4 configured to output a voltage required for a second gate bias voltage for turning the power amplifier 2 to an OFF state; a changeover switch 5 connected between the first power source 3 and the power amplifier 2 and configured to supply either the first gate bias voltage or the second gate bias voltage to the power amplifier 2 by switching a state between the first power source 3 and the power amplifier 2 to either an open state or a short-circuit state on the basis of a control signal related to on-off control of the power amplifier 2; and a resistance value varying unit 15 connected between the second power source 4 and the power amplifier 2 and configured such that a resistance value thereof is variable.

Disclosed are digital predistortion implementations, including a method that includes obtaining a first set of digital predistortion (DPD) non-linear functions for controlling operation of a digital predistorter of a wireless device operating on a received at least one input signal directed to a power amplification system comprising a transmit chain with at least one power amplifier that produces output with non-linear distortions. The method further includes determining an expanded set of DPD non-linear functions comprising the first set of DPD non-linear functions and additional one or more sets of DPD non-linear functions derived based on the first set of DPD non-linear functions and on operating condition parameters associated with operation of the wireless device, and configuring the digital predistorter with DPD coefficients determined for the expanded set of the DPD non-linear functions based on observed samples of the transmit chain responsive to the at least one input signal.

A wireless power transmitting system includes a power amplifier comprising a plurality of measurement points and a power amplifier controller integrated circuit (IC). In some embodiments, the power amplifier controller IC performs synchronization of the various components of the power amplifier, conducts impedance and temperature measurements at the measurements points, determines if a foreign object is within the transmission range of the wireless power transmitter, and decides if a shutdown of the power amplifier is needed. In some embodiments, the power amplifier controller IC determines through a transmitter controller IC, the presence of a foreign object within the transmission range and adjusts the power transmission to one or more receivers.

Embodiments of a method and a device are disclosed. In an embodiment, a method for operating a bias controller for an amplifier circuit involves obtaining temperature data corresponding to a temperature of the amplifier circuit, generating a proportional to absolute temperature (PTAT) bias voltage based on a first PTAT slope when the temperature is within a first range of temperatures or a second PTAT slope when the temperature is within a second range of temperatures, wherein the second PTAT slope is greater than the first PTAT slope, and biasing the amplifier circuit based on the generated PTAT bias voltage.

An electronic device including: a modem configured to process a baseband signal; an intermediate frequency (IF) transceiver configured to convert the baseband signal provided from the modem into an IF band signal; and a radio frequency (RF) transceiver configured to convert the IF band signal provided from the IF transceiver into an RF band signal, wherein the RF transceiver includes a power amplifier configured to amplify the RF band signal, and a temperature sensor unit to detect a temperature of the power amplifier, and wherein the modem includes a controller configured to control an input power inputted to the RF transceiver based on the temperature of the power amplifier detected by the temperature sensor unit.

Temperature compensation circuits and methods for adjusting one or more circuit parameters of a power amplifier (PA) to maintain approximately constant Gain versus time during pulsed operation sufficient to substantially offset self-heating of the PA. Some embodiments compensate for PA Gain droop due to self-heating using a Sample and Hold (S&H) circuit. The S&H circuit samples and holds an initial temperature of the PA at commencement of a pulse. Thereafter, the S&H circuit generates a continuous measurement that corresponds to the temperature of the PA during the remainder of the pulse. A Gain Control signal is generated that is a function of the difference between the initial temperature and the operating temperature of the PA as the PA self-heats for the duration of the pulse. The Gain Control signal is applied to one or more adjustable or tunable circuits within a PA to offset the Gain droop of the PA.

Disclosed are implementations for digital predistortion of signals provided to a radio frequency (RF) transmission path configured to transmit radio signals in a plurality of subbands within a spectral range, including a method that includes configuring a digital predistorter for predistorting signals comprising arbitrary spectral content within the spectral range. The configuring includes acquiring data samples representing operation of the RF transmission path to transmit radio signals in different subbands, each sample including a digital input signal representing spectral content concentrated in a respective subband, and updating parameters of the digital predistorter according to the acquired data samples to mitigate non-linear characteristics of the RF transmission path. The method further includes receiving a further input signal representing spectral content in a particular subband within the spectral range, and using the configured predistorter to process the further input signal to yield a predistorted signal for providing to the RF transmission path.

A control circuit includes a first output unit configured to output a constant bias current for setting an electrical bias state of a bias circuit to the bias circuit; a second output unit configured to output a bias control current or constant voltage for controlling the electrical bias state of the bias circuit to the bias circuit; a resistor having one end connected to a reference potential; and a switch provided between another end of the resistor and an output terminal of the second output unit.

Temperature compensation circuits and methods for adjusting one or more circuit parameters of a power amplifier (PA) to maintain approximately constant Gain versus time during pulsed operation sufficient to substantially offset self-heating of the PA. Some embodiments compensate for PA Gain droop due to self-heating using a Sample and Hold (S&H) circuit. The S&H circuit samples and holds an initial temperature of the PA at commencement of a pulse. Thereafter, the S&H circuit generates a continuous measurement that corresponds to the temperature of the PA during the remainder of the pulse. A Gain Control signal is generated that is a function of the difference between the initial temperature and the operating temperature of the PA as the PA self-heats for the duration of the pulse. The Gain Control signal is applied to one or more adjustable or tunable circuits within a PA to offset the Gain droop of the PA.