Abstract: A server power supply device and method are provided. The server power supply device includes: a filter capacitor, a voltage collecting unit and a processing unit. One terminal of the filter capacitor is connected to a mains electricity input terminal, the other terminal of the filter capacitor is grounded, and a capacitance of the filter capacitor is greater than a preset standard capacitance. The voltage collecting unit is connected to the mains electricity input terminal and the processing unit, and the voltage collecting unit is configured to collect a first voltage inputted from the mains electricity input terminal. The processing unit is configured to process a current inputted from the mains electricity input terminal based on the first voltage collected by the voltage collecting unit, to generate a first current and supply power to a server with the first current.

Abstract: An example apparatus for supporting digital pre-distortion (DPD) and full duplex (FDX) in cable network environments is provided and includes a first path for signals being transmitted out of the apparatus, a second path for signals being received into the apparatus, a DPD actuator located on the first path, an amplifier located on the first path, an echo cancellation (EC) actuator located on the second path, and a data interface including a plurality of channels connecting the apparatus to a signal processor. DPD coefficients, EC coefficients and delay parameters are provided over the data interface from the signal processor to the apparatus. The DPD actuator predistorts signals on the first path using the DPD coefficients compensating for distortions introduced by the amplifier, and the EC actuator reduces interferences in signals on the second path using the EC coefficients and the delay parameters, facilitating FDX communication by the apparatus.

Abstract: Discovery of a neighbor radio access system by a user mobile communications device serviced in a radio access network (RAN) for reporting to a serving system in the RAN. User mobile communications device serviced by a RAN is configured to scan one or more frequency ranges (e.g., bands) to discover other neighbor radio access systems. This is opposed to, for example, the user mobile communications device only searching for transmitted communications signals at specific center frequency (e.g., an EARFCN). There may be other radio access systems that operate neighbor cells and in other frequency bands in proximity the RAN serving the user mobile communications device. Discovered neighboring radio access systems can be reported by the user mobile communications device to its serving RAN in a measurement report, which can then be used by the serving RAN for other functionalities, such as trigger handovers of user mobile communications device for example.

Abstract: A receiving circuit may include an amplifier. The amplifier may include a first amplification circuit and a second amplification circuit. The first amplification circuit may be configured to differentially amplify a first input signal and a reference signal and configured to generate output signals. The second amplification circuit may be configured to differentially amplify a second input signal and the reference signal and configured to generate the output signals.

Abstract: A harmonic distortion separation method, nonlinear character determination method, apparatus and system where a phase difference between an inherent harmonic and a generated harmonic is determined by using multiple groups of input power, output power and fundamental magnitudes of a memoryless nonlinear transfer function of a nonlinear model of a system to be measured, and power of a harmonic generated by the system to be measured is separated by using the phase difference. In an embodiment, the phase difference between the inherent harmonic and the generated harmonic is first determined by using an assumption that a model coefficient is a constant according to the set nonlinear model, then the harmonic separation is performed by using the phase difference, and the power of the harmonic generated by the system to be measured is calculated.

Abstract: A power amplifier includes a power splitter that splits a first signal into a second signal and a third signal, a first amplifier that amplifies the second signal within an area where the first signal has a power level greater than or equal to a first level and that outputs a fourth signal, a second amplifier that amplifies the third signal within an area where the first signal has a power level greater than or equal to a second level higher than the first level and that outputs a fifth signal, an output unit that outputs an amplified signal of the first signal, a first and a second LC parallel resonant circuit, and a choke inductor having an end to which a power supply voltage is supplied and another end connected to a node of the first and second LC parallel resonant circuits.

Abstract: The present invention addresses method, apparatus and computer program product for stabilization of the direct learning algorithm for wideband signals. Thereby, a signal to be amplified is input to a pre-distorter provided for compensating for non-linearity of the power amplifier, and the pre-distorted output signal from the pre-distorter is forwarded to the power amplifier. Parameters of the pre-distorter are adapted based on an error between the linearized signal output from the power amplifier and the signal to be amplified using an adaptive direct learning algorithm, and the linear system of equations formed by the direct learning algorithm are solved using a conjugate gradient algorithm, wherein, once per direct learning algorithm adaptation, at least one of the initial residual and the initial direction of the conjugate gradient algorithm are set based on the result of the previous adaptation.

Abstract: A method for characterizing nonlinear distortion of a transmitter, an associated transmitter and a characterization circuit thereof are provided. The method includes: utilizing a transmitting chain circuit within the transmitter to generate an output signal according to a test signal; utilizing a loop back circuit within the transmitter to generate a loop back signal according to the output signal; calculating a plurality of distorted indices respectively corresponding to a plurality of test samples of the test signal according to a plurality of loop back samples of the loop back signal, wherein the plurality of test samples correspond to the plurality of loop back samples, respectively; dividing the plurality of distortion indices into multiple groups according to power of the plurality of test samples; calculating an average value of distortion indices within each group of the multiple groups; and characterizing the nonlinear distortion of the transmitter according to the average value.

Abstract: A source follower with an input node and an output node includes a first transistor, a second transistor, and a DC (Direct Current) tracking circuit. The first transistor has a control terminal, a first terminal coupled to a first node, and a second terminal coupled to a second node. The second transistor has a control terminal, a first terminal coupled to a ground voltage, and a second terminal coupled to the first node. The DC tracking circuit sets the second DC voltage at the second node to a specific level. The specific level is determined according to the first DC voltage at the first node. The output node of the source follower is coupled to the first node.

Abstract: Digital predistortion methods with power-specific capture selection are disclosed. An example method includes receiving a feedback signal indicative of a power amplifier output and establishing boundaries of multiple ranges of powers in the received signal by analyzing signal statistics in windowed intervals of multiple trial captures. At least one range established in this manner may include the highest value, and at least one other range may include the lowest value of the maximum powers determined for the trial captures. The method further includes updating a power amplifier model based on one or more captures of the feedback signal in each of the K ranges, and using the model to apply digital predistortion to an input signal. By specifically targeting regions of lower power and combining these with high-power captures, the model can be made more representative of the signal as a whole, and signal quality may be improved.

Abstract: An embodiment of the invention is a time-delay invariant predistortion approach to linearize power amplifiers in wireless RF transmitters. The predistortion architecture is based on the stored-compensation or memory-compensation principle by using a combined time-delay addressing method, and therefore, the architecture has an intrinsic, self-calibrating time-delay compensation function. The predistortion architecture only uses a lookup table to conduct both the correction of non-linear responses of a power amplifier and the compensation of any time-delay effects presented in the same system. Due to the time-delay invariant characteristic, the predistortion design has a wider dynamic range processing advantage for wireless RF signals, and therefore can be implemented in multi-carrier and multi-channel wireless systems.

Abstract: Various examples are directed to a power amplifier circuit, comprising a digital predistortion circuit, first and second power amplifiers, and a bias feedback circuit. The digital predistortion circuit may be configured to generate a predistorted input signal based at least in part on an input signal. The first power amplifier may be configured to generate a first amplified signal based at least in part on the predistorted input signal. The second power amplifier may be configured to generate a second amplified signal based at least in part on the predistorted input signal. The bias feedback circuit may be configured to adjust at least one of a bias of the first power amplifier or a bias of the second power amplifier to align a first nonlinear behavior of the first power amplifier with a second nonlinear behavior of the second power amplifier.

Abstract: Apparatus and method for dynamically linearizing multi-carrier power amplifiers. In one example, the method includes storing a correction set including a plurality of correction solutions and loading the correction set into an RF power amplifier linearizer. The method includes determining a first carrier configuration of an RF transmitter during a first timeslot of operation of the RF transmitter and sending a first correction solution index to the RF power amplifier linearizer. The first correction solution index corresponds to a first correction solution of the plurality of correction solutions. The method also includes determining that a carrier configuration change is initiated to operate the RF transmitter with a second carrier configuration during a second timeslot of operation of the RF transmitter and sending a second correction solution index to the RF power amplifier linearizer. The second correction solution index corresponds to a second correction solution of the plurality of correction solutions.

Abstract: A multiantenna communication device forms a directional beam by adding an antenna weight to respective signals of a plurality of antenna elements. The multiantenna communication device includes: a processor that executes performing distortion compensation on a transmission signal by using a distortion compensation coefficient; a plurality of power amplifiers that are provided corresponding to the antenna elements, and that amplify the transmission signal subjected to the distortion compensation by the processor; a multiplexer that multiplexes signals output from the power amplifiers to feed back; and an analog/digital (A/D) converter that A/D converts a multiplex feedback signal that is obtained by the multiplexer, wherein the processor executes updating the distortion compensation coefficient by using the multiplex feedback signal A/D converted by the A/D converter and the transmission signal.

Abstract: An all digital outphasing transmitter includes, at least one decomposition unit for decomposing an input signal to generate a first sub-signal and a second sub-signal; at least one outphasing signal generator to convert said first sub-signal to an outphasing signal; at least one delta sigma modulator to convert said second sub-signal to a delta sigma modulated signal; at least one mixing unit for mixing the outphasing signal and delta sigma modulated signal to generate a first and second mixed signal; at least one first amplifier for amplifying the first mixed signal; at least one second amplifier for amplifying the second mixed signal; at least one combiner for combining the first and second amplified mixed signals to generate a delta sigma modulated output signal and at least one band pass filter for filtering the delta sigma modulated output signal to recover the input signal envelope back on to the output signal.

Abstract: The present disclosure relates to an apparatus and a method for transmitting a signal using a power amplifier in a wireless communication system in which a transceiver comprises a digital pre-distorter configured to distort an input signal based on a distortion control value, a power amplifier configured to amplify an output signal from the digital pre-distorter, an antenna configured to transmit an output signal from the power amplifier, an echo signal canceller configured to remove an echo signal which returns to the power amplifier due to a return loss of a path between the power amplifier and the antenna, from a feedback signal obtained at an output stage of the power amplifier, and a digital pre-distortion adaptation unit configured to determine the distortion control value based on an output signal from the echo signal canceller.

Abstract: Method and apparatus for nonlinear signal processing include mitigation of outlier noise in the process of analog-to-digital conversion and adaptive real-time signal conditioning, processing, analysis, quantification, comparison, and control. Methods, processes and apparatus for real-time measuring and analysis of variables include statistical analysis and generic measurement systems and processes which are not specially adapted for any specific variables, or to one particular environment. Methods and corresponding apparatus for mitigation of electromagnetic interference, for improving properties of electronic devices, and for improving and/or enabling coexistence of a plurality of electronic devices include post-processing analysis of measured variables and post-processing statistical analysis.

Abstract: A frequency multiplier (200) generates an output signal with a frequency 3 times of the input signal frequency. The frequency multiplier (200) comprises four cascaded stages. A first stage (201) is configured to receive an input signal and generate harmonics signals of the input signal. A second stage (202) is a passive filter, a frequency response of the passive filter has either a peak or a dip around an upper frequency end of a frequency band of the input signal. A third stage (203) is configured to mix the 1st and the 2nd order harmonics signals to generate 3rd order harmonic signals. A fourth stage (204) is configured to suppress the 1st and even-order harmonics signals and output a signal dominated with a frequency 3 times of the input signal frequency.

Abstract: An ultrasound diagnostic apparatus according to a present embodiment includes driving pulse generating circuitries and a transmission control circuitry. The transmission control circuitry turns on a switching element of respective driving pulse generating circuitries of the driving pulse generating circuitries to be grounded, and thereby controls so as to make an output impedance of the respective driving pulse generating circuitries become a low impedance. The transmission control circuitry turns off the switching element of the respective driving pulse generating circuitries, and thereby controls so as to make the output impedance become a high impedance by means of a resistance value of the resistance.

Abstract: An electronic transmitter includes: a generator circuit to generate a baseband signal; a modulator circuit to modulate a carrier signal with the baseband signal; an emitter to emit the modulated signal at an intended recipient; and a distortion circuit to apply a final distortion to the baseband signal or the modulated signal. The final distortion is optimized to minimize the ability of unintended recipients to localize the emitter using correlation-based techniques, and to minimize any degradation to the data rate of the emitted signal at the intended recipient. In some cases, the transmitter is part of an electronic communication system that also includes a receiver at the intended recipient. The receiver is aware of the final distortion and includes a collector to collect the emitted signal, and a demodulator circuit to demodulate the collected signal using the final distortion to recover the baseband signal.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for correcting distortion of radio signals A transmit radio signal corresponding to an output of a transmitting radio signal processing system is obtained. A pre-distorted radio signal is then generated by processing the transmit radio signal using a nonlinear pre-distortion machine learning model. The nonlinear pre-distortion machine learning model includes model parameters and at least one nonlinear function to correct radio signal distortion or interference. A transmit output radio signal is obtained by processing the pre-distorted radio signal through the transmitting radio signal processing system. The transmit output radio signal is then transmitted to one or more radio receivers.

Abstract: Embodiments of the present application disclose a passive intermodulation suppression method and a passive intermodulation suppression system. The method in the embodiments of the present application includes: obtaining, by using a target uplink controllable gain module, a first power Pt of an uplink signal sent by an antenna; obtaining a second power Pb of a signal that is output from an output port of a base station; configuring a target attenuation of the base station; and adjusting the initial gain value based on the target attenuation to keep a gain of the base station constant. According to the method described in the embodiments, the base station can maintain the target attenuation constant in a process of adjusting a gain of the target uplink controllable gain module, thereby reducing a PIM requirement of a passive intermodulation suppression system.

Abstract: A linearization circuit that reduces intermodulation distortion in an amplifier output receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency. The linearization circuit generates an envelope signal based at least in part on a power level of the first signal and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal and the adjusted signal at a second terminal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation products that result from the intermodulation of the first frequency and the second frequency.

Abstract: A telecommunications system may include a distortion cancellation subsystem for use with a circulator device coupling an antenna to a transmit path and a receive path. The distortion cancellation subsystem may include a correction circuit and a cancellation circuit. In some aspects, the correction circuit may include a processing device or adaptive filter to correct imperfections in transmit signal samples generated by directional couplers. The correction circuit may also include a summing device to remove receive signal components from the transmit signal samples. The cancellation circuit may receive the output signal of the correction circuit via an adaptive filter. The output of the adaptive filter may be summed with a receive signal to minimize distortion of the receive signal.

Abstract: A DPD operates at a sampling rate at which the input signal not up sampled at an upstream of the DPD is sampled. The DPD includes a polynomial structure comprising a pseudo-interpolation and sub-sample shift processing unit configured to pseudo-interpolate a sample point between the sample points of the input signal and shift the pseudo-interpolated sample point by a sub-sample, and an FIR (Finite Impulse Response) filter disposed at a downstream of the polynomial structure and including a sub-sample delay filter configured to delay the sample point of the input signal by the sub-sample. The DPD uses the polynomial structure and the FIR filter to compensate distortion by the sample point of the input signal and also compensate distortion by a sub-sample point between the sample points of the input signal for the digital predistorter.

Abstract: Digital pre-distortion may be provided. First, a radio frequency (RF) domain distortion correcting signal and a base band (BB) domain distortion correcting signal may be initialized. Then the RF domain distortion correcting signal may be generated from an input signal. The generated RF domain distortion correcting signal may correspond to an amplifier. Next, the BB domain distortion correcting signal may be generated from the input signal. The generated BB domain distortion correcting signal may correspond to the amplifier. Then the RF domain distortion correcting signal and the BB domain distortion correcting signal may be combined to form a hybrid distortion correcting signal. The hybrid distortion correcting signal may then be provided to input matching circuitry feeding the amplifier.

Abstract: An transmitter arrangement and a method therein are provided for linearization of an active antenna array. The active antenna array comprises a plurality of antenna elements, which are associated with a plurality of power amplifiers. The active antenna array is further associated with a precoder having a number of input and output ports. The method comprises obtaining a first signal provided to the antenna array via a first input port of the precoder. The method further comprises adapting a pre-distorting linearizer connected to the first input port based on the first signal and on feedback from the plurality of antenna elements, resulting from the propagation of the first signal via the precoder, and via the plurality of power amplifiers. Embodiments are also provided for adapting a pre-distorting linearizer based on a plurality of input signals and feedback from the plurality of antenna elements.

Abstract: The invention relates to an electrical circuit (1) for transmitting a useful analogue signal which has a signal transmission path (16) with an input path (2) and an output path (3) and one or more switches (4-6), with which switch or switches the useful signal which is carried on the input path (2) can be connected through to the output path (3) by the switch or the switches (4-6) being switched to the switched-on state. According to the invention, the electrical circuit (1) comprises a compensation circuit (7) which has one or more auxiliary switches (17) of the same type as the switch or the switches (4-6), and the auxiliary switch or switches (17) is or are coupled to the signal transmission path (16) such that said auxiliary switch or switches generates or generate signal distortion in the switched-on state, which signal distortion substantially compensates for a distortion in the useful analogue signal which is generated by the switch or switches (4-6).

Abstract: Systems and methods are described for determining a phase measurement difference between a received modulated signal and a local clock signal. An adjusted local clock phase measurement may be determined by subtracting, from the phase measurement difference, a phase correction that is based on the frequency difference between the modulator signal's carrier frequency and the local clock's frequency. A phase modulation value may be generated by scaling the adjusted local clock phase measurement. The scaling may be based on a ratio of the modulated signal's carrier frequency and the local clock's frequency. The phase correction may be based on (i) a count of periods of the modulated signal occurring between each corrected phase measurement and (ii) a difference between the carrier frequency and the local clock frequency.

Abstract: Various examples are directed to systems and methods for digital predistortion (DPD). A linear digital predistortion (DPD) circuit may be programmed to generate a pre-distorted signal linear component based at least in part on a complex baseband signal. A nonlinear DPD circuit may be programmed to generate a pre-distorted signal nonlinear component based at least in part on the complex baseband signal. A mixer circuit programmed to generate a pre-distorted signal based at least in part on the pre-distorted signal linear component and the pre-distorted signal nonlinear component.

Abstract: A power amplifier apparatus supporting reverse intermodulation product (rIMD) cancellation is provided. The power amplifier apparatus includes an amplifier circuit configured to amplify and output a radio frequency (RF) signal for transmission via an antenna port. The antenna port may receive a reverse interference signal, which may interfere with the RF signal to create a rIMD(s) that can fall within an RF receive band(s). A reverse coupling circuit is provided in the power amplifier apparatus to generate an interference cancellation signal based on the reverse interference signal. The amplifier circuit is configured to amplify the interference cancellation signal and the RF signal to create an intermodulation product(s) to suppress the rIMD(s) to a determined threshold. By suppressing the rIMD(s) in the power amplifier apparatus, it is possible to support concurrent transmissions and receptions in a number of RF spectrums while in compliance with stringent regulatory spurious emissions (SEM) requirements.

Abstract: A method for wireless communication includes allocating a transmission bandwidth for transmission to a user equipment (UE). The method further includes determining if the allocated transmission bandwidth is less than or equal to a maximum estimated BWDPD. The maximum estimated BWDPD is the maximum estimated signal bandwidth that a transmitter is configured to digitally pre-distort. The method also includes digitally pre-distorting transmit signals and transmitting the digitally pre-distorted transmit signals to the UE if the allocated transmission bandwidth is less than or equal to the maximum estimated BWDPD. The method also includes transmitting to the UE without digitally pre-distorting the signals if the allocated transmission bandwidth is not less than or equal to the maximum estimated BWDPD. The method also includes applying digital crest factor reduction to the transmit signals if the allocated transmission bandwidth is less than or equal to the maximum estimated BWCFR.

Abstract: A semiconductor device according to an embodiment includes: a first capacitor having a first end and a first the other end, the first end for electrically connecting to at least one of a first electrode and a second electrode of a transistor having the first electrode, the second electrode, and a gate electrode; a first diode having a first anode and a first cathode, the first anode electrically connected to the first the other end; a second capacitor having a second end and a second the other end, the second end electrically connected to the first cathode; a sample and hold circuit electrically connected to the first cathode and the second end; a switch electrically connected in parallel with the second capacitor between the second end and the second the other end; and a second diode having a second anode and a second cathode, the second cathode electrically connected to the first the other end and the first anode.

Abstract: There is provided an apparatus and a method for rapidly extracting a target sound from a sound signal where a variety of sounds are mixed generated from a plurality of the sound sources. There is a voice recognition unit including a tracking unit for detecting a sound source direction and a voice segment to execute a sound source extraction process, and a voice recognition unit for inputting a sound source extraction result to execute a voice recognition process. In the tracking unit, a segment being created management unit that creates and manages a voice segment per unit of sound source sequentially detects a sound source direction, sequentially updates a voice segment estimated by connecting a detection result to a time direction, creates an extraction filter for a sound source extraction after a predetermined time is elapsed, and sequentially creates a sound source extraction result by sequentially applying the extraction filter to an input voice signal.

Abstract: Circuitry and methods are described for digital signal demodulation. In a configurable receiver, a method includes receiving a radio frequency signal at the configurable receiver, operating the configurable receiver in a first mode, the first mode including providing the radio frequency signal to an amplitude detection circuit to determine an amplitude, providing the radio frequency signal to a phase detection circuit to determine a phase, and providing the amplitude and phase to a coordinate rotation digital computer (CORDIC) logic circuit, and operating the configurable receiver in a low power mode upon receiving an indication to selectively disable the amplitude detection circuit, the low power mode including providing the radio frequency signal to the phase detection circuit to determine the phase, and providing the phase and a predetermined constant value in lieu of the amplitude to the CORDIC logic circuit.

Abstract: A radio communication apparatus is disclosed that enables the influence of the feedback information on the channel capacity to be kept to the minimum without reducing the transmission efficiency of information by transmission of pilot symbol. In the apparatus, a delay dispersion measuring section generates a delay profile using the received signal, and measures delay dispersion indicative of dispersion of delayed versions. A moving speed estimating section estimates moving speed of a mobile station apparatus that transmits a pilot symbol based on the variation in reception power of the pilot symbol. An other-cell interference measuring section measures other-cell interference caused by signals transmitted in cells except the cell to which the apparatus belongs.

Abstract: In examples, a system comprises a differential amplifier coupled to a parasitic capacitor positioned between a first node and a first reference voltage source. The system comprises a buffer amplifier having an input terminal and an output terminal, the input terminal coupled to the first node and the output terminal coupled to a cancellation capacitor. The system includes a controlled current source coupled to the first node and the input terminal, the controlled current source coupled to a second reference voltage source. The system comprises a current sense circuit coupled to the cancellation capacitor and the second reference voltage source.

Abstract: A Digital Power-Amplifier (DPA) system includes a power amplifier (PA) circuit having control inputs and an output for generating output signals, and an adaptive control circuit that comprises an input interface, an output interface, a memory storing an adaptive control algorithm and a processor performing instructions based on the adaptive control algorithm in connection with the memory, wherein the input interface receives input-state signals and output signals of the DPA circuit, wherein the adaptive control algorithm determines, in response to the input-state signals and the output signals, control parameters of control signals transmitted to the control inputs from the output interface for controlling operations of the DPA circuit.

Abstract: Embodiments of the disclosure generally relate to a method and device for improving the efficiency of a power amplifier. The apparatus comprising: a harmonic generator, configured to generate one or more harmonic according to an output signal of a power amplifier; a harmonic feedback device, configured to inject the harmonic generated by the harmonic generator to an input terminal of the power amplifier; and a harmonic eliminator, configured to eliminate the harmonic in the output signal of the power amplifier. According to embodiments of the disclosure, the efficiency of power amplifier can be improved without degrading the linearity.

Abstract: The present invention provides an amplifier circuit for amplifying an incoming signal, the amplifier circuit comprising at least two signal paths configured to amplify signals of different overlapping frequency bands, a signal splitter comprising an input port configured to receive the incoming signal, the signal splitter being coupled to an input side of the signal paths and configured to split the incoming signal into split signals for the signal paths, and a diplexer coupled to an output side of the signal paths and configured to combine the amplified signals and provide a combined amplified signal. Further, the present invention provides a respective method.

Abstract: A method and system for digital pre-distortion of an input signal to compensate for non-linear operation of a power amplifier. According to one aspect, some embodiments provide overlapping spline functions that are defined for two adjacent bins, where any two spline functions overlap in only one bin. Each spline function is computed as a function of one of an input signal envelope and a delayed signal envelope. According to another aspect, a tap weight evaluator includes a least mean squares, LMS, tap correlator updater configured to modulate a step size of an adaptation process to update each tap weight, the step size being modulated based on an approximate logarithm of the average power of the input to a tap weight computation.

Abstract: A method and apparatus for reducing capacitor noise in electronic systems is disclosed. A system includes at least one functional circuit block coupled to receive a variable supply voltage. The value of the supply voltage is controlled by a power management circuit. Changing a performance state of the functional circuit block includes increasing the supply voltage for higher performance, and reducing the supply voltage for reduced performance demands. The power management circuit, in changing to a higher performance state, increases the supply voltage at a first rate. A rate control circuit causes the power management circuit to reduce the supply voltage, when changing to a lower performance state, at a second rate that is less than the first rate.

Abstract: Disclosed are systems and methods related to reducing intermodulation products in an RF output signal by matching an impedance of the power amplifier to an impedance of the antenna and concurrently blocking signals having a second fundamental frequency received by the antenna when the antenna is transmitting to inhibit intermodulation products of the first and second fundamental frequencies from re-radiating from the antenna. The matching and blocking are performed concurrently by a single circuit with combined matching and blocking functionality.

Abstract: A 5G base station transmitter at least partially precodes data for beam forming, and generates digital precoded baseband signals. Cross product circuitry coupled to the digital precoder, generates digital cross products of the digital precoded baseband signals. Both the baseband signals and the cross products are put through digital-to-analog converters (DACs), then provided to an analog non-linear precoder. The analog non-linear precoder combines the analog baseband signals, the cross products, with pre-distortion and precoder coefficients to generate a signal that is pre-compensated for power amplifier non-linearity. The pre-compensated signal is amplified by the power amplifier and transmitted via a phased antenna array. The number of extra DACs required for inserting pre-distortion when a hybrid digital/analog precoder is used can be limited to approximately N RF ? ( N RF - 1 ) 2 , where NRF is the number of outputs of the digital precoder.

Abstract: An approach to digital compensation uses a particular structure for a digital pre-distorter (DPD) which acts as a relatively accurate pre-inverse of a non-linear circuit (e.g., a non-linear transmit chain involving digital-to-analog converter (DAC), lowpass filter, modulator, bandpass filter, and power amplifier) while making use of a relatively small number of parameters that characterize the non-linearity and/or parameters that provide accurate linearization without requiring continual updating.

Abstract: A frequency calibration device includes an input signal generator configured to generate an input signal based on an oscillation signal and an external signal, an envelope detector configured to detect an envelope signal corresponding to the input signal, and a frequency tuner configured to tune an oscillation frequency of the oscillation signal based on an envelope frequency corresponding to the envelope signal.

Abstract: An RF transmitter arrangement using analog pre-distortion is disclosed. The arrangement includes lower bandwidth circuitry, an analog pre-distorter, and a non-linear amplifier chain. The lower bandwidth circuitry is configured to generate an analog signal. The analog pre-distorter is configured to apply a non-linear distortion to the analog original signal based on a coupled feedback signal in order to generate an RF output signal. The non-linear amplifier chain is configured to amplify the RF output signal to generate a transmission signal relative to the analog original signal. The coupled feedback signal is derived from the transmission signal.

Abstract: A predistorter has a first capacitor and an impedance conversion circuit. A first end of the first capacitor is coupled to a first node of the amplifier. The impedance conversion circuit is used to perform an impedance conversion to provide a variable capacitance. The impedance conversion circuit has a first bias input circuit and a bipolar junction transistor (BJT). The first bias input circuit is used to receive a first input bias. A base of the BJT is coupled to an output end of the first bias input circuit and a second end of the first capacitor, a collector of the BJT is floating, and an emitter of the BJT is coupled to a second node of the amplifier.

Abstract: Circuits and methods for adjusting one or more operation parameters of a semiconductor device. One example of a circuit includes a first semiconductor device, a beta sensing circuit coupled to the first semiconductor device and configured to measure a current gain of the first semiconductor device and generate a first control signal based on a value of the current gain of the first semiconductor device, and a reference control circuit coupled to the beta sensing circuit and configured to receive the first control signal and adjust an operation parameter of the first semiconductor device based on the value of the current gain of the first semiconductor device.

Abstract: A same-aperture any-frequency simultaneously transmit and receive (STAR) system includes a signal connector having a first port electrically coupled to an antenna, a second port electrically coupled to a transmit signal path, and a third port electrically coupled to receive signal path. The signal connector passes a transmit signal in the transmit signal path to the antenna and a receive signal in the receive signal path. A signal isolator is positioned in the transmit signal path to remove a residual portion of the receive signal from transmit signal path. An output of the signal isolator provides a portion of the transmit signal with the residual portion of the receive signal removed. A signal differencing device having a first input electrically coupled to the output of the signal isolator and a second input electrically coupled to the third port of the signal connector subtracts a portion of the transmit signal in the receive signal path thereby providing a more accurate receive signal.