Abstract: A pulse width modulation system comprises an analog component and a digital component. The analog component operates to separate a local oscillator signal with different phase shifts and introduce an offset (i.e., a time delay) to analog signals being receive at an input with a tuning operation that fine tunes in the analog signals in the analog (continuous time) domain. The analog component comprises a plurality of analog delay lines that respectively process carrier signals having a different phase shifts. Digital delay lines convert the analog signals to digital square waves with the same time delay and at the same resolution as the analog output 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 peaking amplifier is disclosed. The peaking amplifier includes a driver stage, a final stage, and an interstage matching network. The driver stage has a load impedance and is configured to generate a driver output based on an input signal. The final stage has a final stage input impedance and is configured to generate a peaking output based on the driver output. The interstage matching network is coupled to the driver stage and the final stage. The interstage matching network is configured to transform the final stage input impedance to the load impedance for the driver stage when the peaking amplifier is ON and to provide a short to an input of the final stage when the peaking amplifier is in an OFF state.

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: 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: The present disclosure relates to a low-complexity transmitter architecture that drives phase modulators with digital signals to generate a pulse width modulated (PWM) signal that is transmitted by an antenna. In some embodiments, the system has a pre-processing element that generates first and second digital control signals from a digital baseband signal. A first phase modulation component introduces a first phase shift into a first local oscillator signal based upon the first control signal and generates a first digital signal corresponding to the first phase shift. A second phase modulation component introduces a second phase shift into the first local oscillator signal based upon the second control signal and generates a second digital signal corresponding to the second phase shift. A combination element is configured to combine the first and second digital output signals to generate an RF pulse width modulated (RF-PWM) signal.

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: The present disclosure relates to a low-complexity transmitter architecture that drives phase modulators with digital signals to generate a pulse width modulated (PWM) signal that is transmitted by an antenna. In some embodiments, the system has a pre-processing element that generates first and second digital control signals from a digital baseband signal. A first phase modulation component introduces a first phase shift into a first local oscillator signal based upon the first control signal and generates a first digital signal corresponding to the first phase shift. A second phase modulation component introduces a second phase shift into the first local oscillator signal based upon the second control signal and generates a second digital signal corresponding to the second phase shift. A combination element is configured to combine the first and second digital output signals to generate an RF pulse width modulated (RF-PWM) signal.

Abstract: One embodiment relates to a system which includes a pre-distortion unit, a power amplifier circuit, a power amplifier model, and a parameter estimation unit. The pre-distortion unit is configured to pre-distort an input signal based on a model parameter by directly computing the model inverse in an iterative fashion, thereby providing a pre-distorted signal. The power amplifier circuit is configured to amplify the pre-distorted signal. The power amplifier model is configured to model amplification of the pre-distorted signal by the power amplifier circuit based on the pre-distorted signal and the model parameter. Based on the pre-distorted signal and an error signal, the parameter estimation unit is configured to update the model parameter provided to the pre-distortion unit and the power amplifier model. The error signal represents a difference between an output signal from the power amplifier circuit and a modeled output signal from the power amplifier model.

Abstract: A nonlinear distorter is configured to mitigate nonlinearity from a nonlinear component of a nonlinear system. The nonlinear distorter operates to model the nonlinearity as a function of a piecewise polynomial approximation applied to segments of a nonlinear function of the nonlinearity. The nonlinear distorter generates a model output that decreases the nonlinearity of the nonlinear component.

Abstract: A nonlinear distorter is configured to mitigate nonlinearity from a nonlinear component of a nonlinear system. The nonlinear distorter operates to model the nonlinearity as a function of a piecewise polynomial approximation applied to segments of a nonlinear function of the nonlinearity. The nonlinear distorter generates a model output that decreases the nonlinearity of the nonlinear component.

Abstract: In an embodiment, a method of generating a pulse-width modulated signal from an input signal includes calculating a finite number of basis functions of a first pulse-width modulated signal based on the input signal, and forming an electronic output based on the calculated finite number of basis functions.

Abstract: A nonlinear distorter is configured to mitigate nonlinearity from a nonlinear component of a nonlinear system. The nonlinear distorter operates to model the nonlinearity as a function of a piecewise polynomial approximation applied to segments of a nonlinear function of the nonlinearity. The nonlinear distorter generates a model output that decreases the nonlinearity of the nonlinear component.

Abstract: A method for providing cross point information includes: providing an input signal having amplitude and phase information; interpolating between a first point of the input signal and a second point of the input signal to provide cross point information between the first point and the second point; and providing a pulse-width modulated signal based on the input signal and the cross point information.

Abstract: A method for providing cross point information includes: providing an input signal having amplitude and phase information; interpolating between a first point of the input signal and a second point of the input signal to provide cross point information between the first point and the second point; and providing a pulse-width modulated signal based on the input signal and the cross point information.

Abstract: In accordance with an embodiment, a system includes a first amplifier and a first bandpass filter having an input coupled in series with an output of the first amplifier, and an output configured to be coupled to a load. The bandpass filter has a lower input impedance at an in-band center frequency than at out-of-band frequencies, and the first amplifier is configured to receive a pulse width modulated waveform filtered according to a first transfer function that attenuates sidebands of the pulse width modulated waveform.

Abstract: In an embodiment, a method of producing a multi-level RF signal includes producing plurality of pulse-width modulated signals based on an input signal. The method further includes driving a corresponding plurality of parallel amplifiers with the plurality of pulse-width modulated signals by setting a parallel amplifier to have a first output impedance when a corresponding pulse-width modulated signal is in an active state and setting the parallel amplifier to have a second output impedance when the corresponding pulse-width is in an inactive state. The method also includes phase shifting the outputs of the plurality of parallel amplifiers, wherein phase shifting transforms the second output impedance into a third impedance that is higher than the second output impedance, and combining the phase shifted outputs.

Abstract: In an embodiment, a method of generating a pulse-width modulated signal from an input signal includes calculating a finite number of basis functions of a first pulse-width modulated signal based on the input signal, and forming an electronic output based on the calculated finite number of basis functions.

Abstract: A pulse-width modulator (PWM) includes a plurality of comparators for comparing an input signal with a plurality of reference signals and for providing a plurality of corresponding comparison signals. The pulse-width modulator also includes a combinational logic for receiving the plurality of comparison signals and for generating a plurality of binary pulse-width modulation signals on the basis of the plurality of comparison signals. At most only a currently selected binary pulse-width modulation signal of the binary pulse-width modulation signals is at a first signal level at a time. The currently selected binary pulse-width modulation signal is associated to a specific reference signal of the plurality of reference signals which is currently closest to the input signal among the plurality of reference signals in terms of a given amplitude relation between the plurality of reference signals and the input signal.

Abstract: In accordance with an embodiment, a system includes a first transistor and a second transistor. The first transistor has a first input node coupled to a first signal input, a first output node coupled to a first common node, and a first reference node coupled to a first reference voltage, and the second transistor has a second input node coupled to second signal input, a second output node coupled to an output of the system, and a second reference node coupled to the first common node. The system further includes a first switch switchably coupling the first common node to a second reference voltage.