Abstract: An ultrasound imaging system includes a plurality of processing chains (2061, . . . , 206K) for a plurality of transducer element channels (1081, . . . , 108K). A processing chain of the plurality of processing chains, includes: a phase rotation processor (1141, . . . , 114K) that focuses an N-bit digital representation, of an analog RF signal received on the corresponding transducer element channel, through phase rotation through phase additions or subtractions, and outputs a focused N-bit quantized value, where N is a predetermined positive integer.

Abstract: Aspects of a method and system for high-speed, low-power optical communications are provided. In one embodiment, a system for optical communications comprises a digital-to-analog converter (DAC), a driver, and a transmit optical subsystem. The DAC is operable to receive a digital code of a plurality of digital codes and output an analog current signal having an analog current level of a plurality of analog current levels. The driver is operable to condition the analog current signal output from the digital-to-analog converter. The transmit optical subsystem is operable to generate an optical power signal from the conditioned analog current signal. A mapping between the plurality of digital codes and the plurality of analog current levels is dynamically controlled according to one or more characteristics of the optical power signal. The one or more characteristics comprise or a symbol amplitude sensitivity and/or a nonlinearity that may be temperature dependent.

Abstract: An apparatus to apply frequency selective digital predistortion (DPD) to a power amplifier (PA) circuit is disclosed. The apparatus comprises a first transformation circuit configured to receive a PA input comprising a quantity indicative of an input signal of the PA circuit and process the PA input by applying a first predetermined weighted function, to form a processed PA input, and a second transformation circuit configured to receive a PA output comprising a quantity indicative of an output signal of the PA circuit and process the PA output by applying a second predetermined weighted function, to form a processed PA output. The apparatus further comprises a coefficient computation circuit configured to receive the processed PA input and the processed PA output; and estimate distortion coefficients, to be utilized for predistorting the input signal of the PA circuit, based on the processed PA input and the processed PA output.

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: An adaptive linearizer system includes an adaptive linearizer circuit that is configured to pre-distort an input signal based on one or more control signals to generate a pre-distorted signal, and a non-linear high-power amplifier (HPA) having non-linear characteristics that is coupled to the adaptive linearizer circuit. The nonlinear HPA amplifies the pre-distorted signal. The pre-distortion characteristics of the adaptive linearizer circuit provide for countering the non-linear characteristics of the non-linear HPA and compensating a non-linearity of the non-linear HPA.

Abstract: A technique for determining a time alignment (TA) error in a circuitry is provided. One or few measurement cycles can be utilized for a closed-loop TA alignment, e.g., for envelope tracking in a transmitter. As to a method aspect of the technique, the amplitudes of a first signal and a second signal are determined. A first measure is computed that is indicative of a relative amplitude error, and a second measure is computed that is indicative of a variation of at least one of the amplitudes. The TA error is determined by correlating the first and second measures.

Abstract: A power amplifier gain attenuation circuit includes: a gain attenuation (reduction) circuit configured to receive an input signal, an external drive signal and a bias voltage, and output a secondary input signal after attenuating the input signal depending on the drive signal and bias voltage; an amplifier including: a bias input terminal configured to receive a bias voltage; a signal input terminal configured to receive a secondary input signal, and an output terminal configured to output a gained output signal. The power amplifier gain attenuation circuit can reduce a gain effectively, and the amount of phase jump caused by the attenuation is quite small.

Abstract: Digital pre-distortion is performed on a received signal using a set of pre-distortion coefficients to produce a digital pre-distorted signal. The digital pre-distorted signal is converted to an analog signal, which is amplified to produce a transmission output signal. The transmission output signal is converted to a digital feedback signal. A plurality of fractional delay filters is applied to the digital feedback signal to obtain a plurality of fractional delay compensated (FDC) candidates, and gain compensation is applied to each of the plurality of FDC candidates to obtain a plurality of gain and fractional delay compensated (XFT) candidates. The digital pre-distorted signal is used as a reference signal, and the XFT candidates and the reference signal are used to select a selected XFT candidate of the plurality of XFT candidates. The selected XFT candidate is used to generate the set of pre-distortion coefficients.

Abstract: An apparatus and a method for controlling power consumption of a terminal in a wireless communication system are provided. The method includes deactivating one or more of hardware components for signal reception in a transmission interval if there is no data to be received in the transmission interval, and receiving a control signal by activating all the components in a next transmission interval.

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 high throughput satellite communication system and method of satellite communication that provide loopback capability and increased throughput is disclosed. The satellite communication system and method of satellite communication utilize pre-distortion based on remotely estimated characteristics of a satellite transponder's power amplifier (PA). The pre-distortion is applied to the hub modulator's constellation.

Abstract: A delay estimation method for a multiple input multiple output communications system, includes: calculating, by a receiver, a channel response matrix of a Multiple input multiple output MIMO communications system, where there are n transmit channels and m receive channels in the MIMO communications system, n?2, m?2, and the channel response matrix includes channel responses of n*m sub-channels; calculating, by the receiver, an integer delay, relative to a reference sub-channel, of each of the n*m sub-channels according to the channel response matrix, where the reference sub-channel is any sub-channel in the n*m sub-channels; calculating, by the receiver, fraction delays of the n*m sub-channels according to the channel response matrix; and separating out, by the receiver, delays of the m receive channels according to delays of the n*m sub-channels.

Abstract: Provided is a receiver including an oscillator (OSC) configured to generate an oscillation signal based on a radio signal, a clocked envelope detector (ED) configured to detect an envelope of the oscillation signal and hold a peak value of the envelope during a time interval, and an analog-to-digital converter (ADC) configured to convert the peak value of the envelope into a digital signal.

Abstract: A low noise amplifier (LNA) reduces matching and switch noise. The LNA includes a main radio frequency signal path, an auxiliary radio frequency signal path and a phase shifter. The main path includes a first transistor and an inductor. The inductor is positioned between an input port of the LNA and the first transistor. The first transistor receives an input radio frequency signal via the inductor and provides a first amplified signal based on the input radio frequency signal. The auxiliary radio frequency signal path provides a second amplified signal for a noise cancellation mode based on the input radio frequency signal. The phase shifter applies a phase shift to an output signal of the LNA based on the first amplified signal and the second amplified signal.

Abstract: A controller can include a signal generator configured to provide an input signal to a modulator. The controller can be configured to generate a modulator compensation parameter in response to a modulated feedback signal corresponding to an output of the modulator. The controller can also be configured to generate a power amplifier predistortion signal in response to an amplified feedback signal corresponding to an output of a power amplifier coupled to the modulator.

Abstract: A method and apparatus for intermodulation product (IMP) cancellation. In one embodiment, the method comprises: acquiring copies of source signals that create IMPs in a passband of interest; creating copies of the IMPs for use as IMP cancellation signals by either multiplying the source signals together as a series of digital samples such that the multiplied signals create a near real and continuous time copy of the IMPs or creating a sum of the source signals in near real and continuous time and convolving the sum of the source signals with a mathematical model to effectively multiply the signals together to create a copy of the IMPs; adjusting one or both of phase and amplitude of the copies; and using the copies to cancel the IMPs inband of the passband of interest.

Abstract: An apparatus for controlling the gain and phase of an input signal input to a power amplifier comprises a gain control loop configured to control the gain of the input signal based on power levels of the input signal and an amplified signal output by the power amplifier, to obtain a predetermined gain of the amplified signal, and a phase control loop configured to obtain an error signal related to a phase difference between a first signal derived from the input and a second signal derived from the amplified signal, and control the phase based on the error signal, to obtain a predetermined phase of the amplified signal. The phase control loop delays the first signal such that the delayed first signal and the second signal used to obtain the error signal correspond to the same part of the input signal. The apparatus may be included in a satellite.

Abstract: A predistortion system for correcting a distortion of a distorting component is provided. It comprises a signal generator, adapted to generate a first signal based upon a reference signal, the distorting component, adapted to generate a second signal, based upon the first signal, and an iterative predistortion device, adapted to determine a compensated signal based upon the second signal and the reference signal. The signal generator is adapted to use the compensated signal as reference signal in further iterations after a first iteration. The predistortion system moreover comprises a predistortion calculation device, adapted to determine a predistortion function based upon the reference signal and the first signal. The signal generator is then adapted to generate the first signal based upon the predistortion function for further reference signals.

Abstract: An analog time delay filter circuit including a first delay circuit block arranged in a modular layout, having a first time delay filter, a first input, a first output, and first and second pass-throughs; a second delay circuit block arranged in the same modular layout, having a second time delay filter, a second input, a second output, and third and fourth pass-throughs; and an interposer circuit block that electrically couples the second input to the first pass-through and the second output to the second pass-through.

Abstract: In a mobile communication service system, repeaters can be installed to cover shadow areas where it may otherwise be difficult to transmit and/or receive mobile signals. A radio frequency (RF) repeater that may select between an interference cancellation device and a software-defined radio (SDR) device is provided. The RF repeater can select use of the interference cancellation device in environments or situations that are relatively less complex, and can switch to use of the SDR device instead for environments or situations where more complex frequency processing may be needed and where such frequency processing may be prioritized over interference cancellation to provide better or more effective signal transmissions.

Abstract: An adaptive digital pre-distortion system includes a transmitting module and a receiving module. The transmitting module is configured to receive a first signal and includes a modulator, pre-distortion module, and transmitting circuit. The pre-distortion module is coupled to the modulator to perform a pre-distortion operation in accordance with the first modulation signal and generate a first pre-distortion signal. The transmitting circuit generates a first transmitted signal in accordance with the first pre-distortion signal. The receiving module is configured to receive the first transmitted signal and includes a receiving circuit, demodulator, and prediction module.

Abstract: The present document discloses an apparatus and method for nonlinear system distortion correction. The apparatus includes: apparatus for nonlinear system distortion correction including: a robustness signal source generator, arranged to generate a robustness signal provided to an adaptive device; the adaptive device, arranged to collect a main link signal output by a signal generator and a feedback signal returned by the main link signal via a feedback link, and generate a correction parameter according to the main link signal, the feedback signal and the robustness signal; and a pre-corrector, arranged to according to the correction parameter perform pre-correction processing on the main link signal output by the signal generator.

Abstract: A remote radio head unit (RRU) system is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier inside the RRU. The power amplifier characteristics such as variation of linearity and asymmetric distortion of the amplifier output signal are monitored by a wideband feedback path and controlled by the adaptation algorithm in a digital module. Therefore, embodiments of the present invention can compensate for the nonlinearities as well as memory effects of the power amplifier systems and also improve performance, in terms of power added efficiency, adjacent channel leakage ratio and peak-to-average power ratio. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers, multi-frequency bands and multi-channels.

Abstract: A wireless receiver includes an antenna receiving a right-handed circularly polarized (RHCP) signal and a left-handed circularly polarized (LHCP) signal, a first amplifier and a second amplifier coupled to the antenna, an intermediate summer coupled to the first and second amplifiers and providing a first intermediate signal, an intermediate subtractor coupled to the first and second amplifiers and providing a second intermediate signal. The wireless receiver also includes a V-signal summer providing a V-component output based on a sum of the first intermediate signal and the second intermediate signal, and an H-signal subtractor providing an H-component output based on a difference between the first intermediate signal and the second intermediate signal. The wireless receiver is configured to provide the V-component output and the H-component output without using a phase shifter.

Abstract: A distortion compensation circuit includes a low-pass circuit to block the passage of two-wave RF signals and intermodulation distortions and to allow the passage of a difference-frequency signal. The low-pass circuit is connected between a signal path and an intermodulation distortion adjustment circuit.

Abstract: A high-speed serial interface includes a transmitter having an output module with settings that select an output impedances of the output module and a tuning value for the output impedance, and a receiver having a plurality of compensation modules each to provide a selectable level of equalization to a data bitstream from the transmitter, and a control module that directs the transmitter to successively select each of the tuning values, that directs the compensation modules, for each tuning value, to successively select each of the levels of equalization, that evaluates an indication of a performance level of the receiver for each of the successively selected levels of equalization and for each of the tuning values, and that selects a particular tuning value based upon the indications of the performance level of the receiver.

Abstract: A method of determining a transmission time of a packet in a mobile device according to the present disclosure may include: if a request for the transmission of a present packet from at least one operated application is detected, identifying whether it is possible to delay a transmission time of the present packet; when it is possible to delay the transmission time of the present packet, calculating a power gain generated as the transmission time of the present packet is delayed; and determining whether the transmission time of the present packet will be delayed according to the calculated power gain.

Abstract: An efficient baseband predistortion linearization method using effective multiplexing modulation technique such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. The present invention is based on the method of piecewise pre-equalized lookup table based predistortion, which is a cascade of a lookup table predistortion and piecewise pre-equalizers.

Abstract: A multi-channel predistortion method and apparatus are disclosed. The technical method provided in the embodiment of the present invention includes: determining a channel index of a current channel to be processed; performing handover to the current channel according to a determined channel index; collecting forward data and reverse data of the current channel, and estimating a predistortion coefficient; and performing predistortion compensation on forward data of each channel according to a corresponding predistortion coefficient. In the embodiments of the present invention, by using a jumping polling mode on a channel time, the predistortion efficiency under multiple channels is improved. In addition, by means of all channels or a plurality of channels sharing N power levels, the resource utilization rate is improved.

Abstract: The present disclosure describes a method and system for linearizing an amplifier using transistor-level dynamic feedback. The method and system enables nonlinear amplifiers to exhibit linear performance using one or more of gain control elements and phase shifters in the feedback path. The disclosed method and system may also allow an amplifier to act as a pre-distorter or a frequency/gain programmable amplifier.

Abstract: An integrated circuit includes a degeneration network configured to improve group delay across one or more variations, wherein the degeneration network includes a transimpedance amplifier with one or more degeneration inductors. The transimpedance amplifier further includes one or more transistors, and the one or more degeneration inductors are connected after at least one emitter of the one or more transistors.

Abstract: A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.

Abstract: A non-linear pre-distortion engine maintaining constant peak power at its output is disclosed. The engine includes a compression estimator, a crest factor reduction processor, a digital pre-distorter and a power amplifier. The compression estimator is configured to generate a compression estimate based on an input signal and a feedback signal. The feedback signal is based on an RF output signal. The crest factor reduction processor is configured to reduce a crest factor of the input signal to generate a crest factor reduced signal based on the compression estimate. The digital pre-distorter is configured to apply a pre-distortion to the crest factor reduced signal after an initial phase and generate a pre-distorted signal based on pre-distortion parameters. The power amplifier is configured to amplify the pre-distorted signal to generate the RF output signal.

Abstract: This application relates to audio amplifier circuitry (100). An amplifier module (103) is located in a signal path between an input (101) and an output (102). A detection module (106) is configured to detect a characteristic of a load (104) electrically coupled, in use, to the output. A distortion setting controller (107) is provided for selecting one of a plurality of stored distortion settings {pi} based on the detected characteristic of the load; and a pre-distortion module (105) is configured to apply a first transfer function to a signal in the signal path prior to said amplifier module. The first transfer function is based on the selected distortion setting and for at least one of the stored distortion settings the corresponding first transfer function comprises a non-linear distortion function.

Abstract: A series-type Doherty amplifier circuit includes a first amplifier, a second amplifier, and a directional coupler. The first amplifier is of a first type and has an input for receiving a radio frequency input signal, and an output. The second amplifier is of a second type and has an input and an output. The directional coupler has a first terminal coupled to the output of the first amplifier, a second terminal coupled to the input of the second amplifier, and a third terminal coupled to the output of the second amplifier for providing a radio frequency output signal. The series-type Doherty amplifier circuit may also include variable phase and attenuation circuits for adjusting the phase and attenuation of input signal for the second amplifier. The ability to adjust phase and attenuation allows high operating efficiency for any saturation power level.

Abstract: An integrative software radio embodies a single multi-radio device including functionalities that are a superset of a plurality of individual discrete radio devices includes a radio frequency transmitter that integrates transmission capabilities of a plurality of discrete transmitters such that the radio frequency transmitter is configured to generate a first amalgamated waveform that is a combination of individual waveforms, each individual waveform corresponding to the transmission capabilities of its respective one of the plurality of discrete transmitters, wherein the transmission capabilities each of the plurality of discrete transmitters comprise operating characteristics different from one or more of the other discrete transmitters, wherein a waveform of a discrete transmitter comprises an adjustable electromagnetic wavefront and a proprietary waveform generation component; and a mission module communicatively coupled to the plurality of discrete transmitters and configured to alter the wavefront of at

Abstract: A device includes a first amplifier coupled to a first signal conduction path and a second amplifier coupled to a second signal conduction path. A first coupler is coupled to the first signal conduction path. The first coupler is configured to produce an output signal based on a first signal carried by the first signal conduction path. A delay element is configured to impose a phase delay on the output signal of the first coupler to generate a delayed output signal. The device includes a second coupler coupled to the second signal conduction path. The second coupler is connected to the delay element and configured to inject the delayed output signal into the second signal conduction path.

Abstract: A wideband highly linear amplifier includes a plurality of pre-distortion units for respectively linearizing digital signals of a plurality of bands, a synthesis unit for synthesizing output signals of the pre-distortion units, a single amplifier for amplifying signals outputted from the synthesis unit, distribution units for respectively separating the signals for each of the plurality of bands from the output signals of the amplifier, a plurality of inverse compensation attenuators for respectively attenuating the separated signals for each of the plurality of bands, and a feedback path for respectively feeding the attenuated signals for each of the plurality of bands back into the pre-distortion unit of the corresponding band out of the plurality of the pre-distortion units.

Abstract: Reduced latency video stabilization methods and tools generate truncated filters for use in the temporal smoothing of global motion transforms representing jittery motion in captured video. The truncated filters comprise future and past tap counts that can be different from each other and are typically less than those of a baseline filter providing a baseline of video stabilization quality. The truncated filter future tap count can be determined experimentally by comparing a smoothed global motion transform set generated by applying a baseline filter to a video segment to those generated by multiple test filter with varying future tap counts, then settings the truncated filter future tap count based on an inflection point on an error-future tap count curve. A similar approach can be used to determine the truncated filter past tap count.

Abstract: A distortion compensation device includes: a storage configured to store a distortion compensation coefficient for compensating a distortion of a transmission signal to be amplified and transmitted, by corresponding to a combination of a plurality of addresses; a first generator configured to generate a first address according to a power or an amplitude of an input signal; a second generator configured to generate a second address according to a first vector to interconnect sample points on an IQ plane where the sample points of the input signal are drawn in time series; and a distortion compensation unit configured to acquire the distortion compensation coefficient corresponding to a combination of the first address and the second address from the storage, and to perform a predistortion processing on the input signal, by using the acquired distortion compensation coefficient, so as to generate the transmission signal.

Abstract: A radio communication device includes: an instantaneous coefficient acquisition unit that acquires an instantaneous coefficient that corrects an instantaneous change contained in a burst distortion corresponding to an elapsed time from a top of a burst signal in which a constant power level continues and instantaneously changes the power level of the burst signal; an average coefficient acquisition unit that acquires an average coefficient that corrects an average change contained in the burst distortion and gradually changes the power level of the burst signal from the top to an end of the burst signal; a synthesizer that synthesizes the instantaneous coefficient acquired by the instantaneous coefficient acquisition unit with the average coefficient acquired by the average coefficient acquisition unit; and a corrector that uses a correction coefficient obtained from the synthesizing by the synthesizer to correct the burst distortion occurring in the burst signal.

Abstract: A radio frequency (RF) front end chip in a phased array antenna panel for transmitting a modulated circularly-polarized signal is disclosed. The RF front end chip includes an oscillator providing an angular speed modulation signal to a quadrature generation block, the quadrature generation block providing an in-phase signal and a quadrature signal based on the angular speed modulation signal, a first amplifier receiving the in-phase signal and a data signal, and providing a modulated horizontally-polarized signal, and a second amplifier receiving the quadrature signal and the data signal, and providing a modulated vertically-polarized signal, where a modulated circularly-polarized signal is generated based on the modulated horizontally-polarized signal and the modulated vertically-polarized signal. The angular speed modulation signal controls an angular speed of the modulated circularly-polarized signal. The data signal is encoded by the angular speed modulation signal.

Abstract: A signal amplification method includes receiving, from a capacitive sensor, a first input signal by a first control terminal of a first transistor, and a second input signal by a first control terminal of a second transistor. The method also includes producing a first output signal, including amplifying a first signal at a first load path terminal of the first transistor using a first inverting amplifier having an output coupled to a resistance network, and producing a second output signal, including amplifying a second signal at a first load path terminal of the second transistor using a second inverting amplifier having an output coupled to the resistance network. The method also includes feeding back the first and second output signal to a second load path terminal of the first transistor and to a second load path terminal of the second transistor via the resistance network according to a pre-determined fraction.

Abstract: Embodiments contained in the disclosure provide a method of cancelling power supply noise that affects the output of a class-D audio amplifier. The method begins when an alternating current (AC) coupled signal is input into an inverting amplifier. That signal is then amplified in the inverting amplifier. The amplified AC coupled signal is then feed through a resistor capacitor (RC) network, and from the RC network to an inverting input of the inverting amplifier. The output of a high pass filter is used to cancel the power supply ripple signal as the output of the high pass filter is injected into a supply voltage line. The cancelling signal is opposite in magnitude to the power supply ripple signal. The apparatus includes an inverting amplifier, a capacitor for coupling to an AC signal, and a resistor, in combination with the capacitor.

Abstract: In some examples, a circuit is configured to generate a first signal based at least in part on an input signal, wherein the first signal comprises a common mode signal and a load signal. The circuit is further configured to generate a second signal based at least in part on the input signal, wherein the second signal comprises an inverted version of the common mode signal. The circuit is further configured to apply the first signal and the second signal to a load.

Abstract: A digital optical transmitter of the present invention comprises an optical modulator, pre-equalization factor computation means for generating transform functions for compensating waveform distortion to occur in the optical modulator, and pre-equalization signal generation means for outputting third data and fourth data after creating them by performing a pre-equalization process on first data and second data. Here, through the transform functions, the first data is added to the fourth data, in a manner depending on a characteristic of the optical modulator, and the second data is added to the third data, in a manner depending on a characteristic of the optical modulator.

Abstract: A method and an apparatus for determining validity of samples for a digital pre-distortion apparatus is disclosed. It is an object of at least one embodiment to provide a method and an apparatus for determining validity of samples for a digital pre-distortion apparatus that is configured to compensate for nonlinearity of a power amplifier in an efficient manner by accurately estimating a pre-distortion coefficient with a low-capacity memory.

Abstract: A power detector for detecting an output power of a power amplifier is provided. The power amplifier is used to transmit signal power to the antenna. The power detector includes a phase shifter, a multiplier and a calibration unit. The phase shifter sequentially applies a plurality of candidate phase calibration amounts to the output voltage of the power amplifier to generate a plurality of adjusted signals with different phases in a calibration mode. The multiplier sequentially mixes the replica current and each of the plurality of adjusted signals, to generate a plurality of analog signals with different phases. The calibration circuit determines a target phase calibration amount of the phase shifter from the candidate phase calibration amounts according to the plurality of analog signals.

Abstract: An embodiment of an amplifier system includes a modifiable signal adjustment device with an RF signal adjustment circuit coupled between first and second nodes. The RF signal adjustment circuit includes an adjustable phase shifter and an adjustable attenuator coupled in series with each other. The device also includes a memory and a controller circuit. The controller circuit retrieves a phase shift value and an attenuation value from the memory. The controller circuit then controls the adjustable phase shifter to apply a phase shift corresponding to the phase shift value to an input RF signal received at the first node, and controls the adjustable attenuator to apply an attenuation corresponding to the attenuation value to the input RF signal. Applying the phase shift and the attenuation results in an output RF signal at the second node.

Abstract: A method of compressing the audio dynamics of an audio signal. The method includes a step of acquiring an audio signal; a step of selecting a first instant of the audio signal; a step of calculating a plurality of partial gains corresponding, respectively, to a plurality of observation windows of the audio signal that are centered on the first instant, the width of the observation windows following a geometric progression with a rate and first term that are predefined; a step of summing the partial gains calculated in a first corrective term; and a step of applying the first corrective term to the audio signal at the first instant.