Abstract: For generating quantized signals, a quantized phase domain related to quantized phases of an input signal is generated. Vectors that the input signal may occupy are calculated based on the quantized phase domain. A first quantized phase of a first component of the input signal is generated per the quantized phase domain, and a second quantized phase of a second component of the input signal is generated per the quantized phase domain.

Abstract: The present disclosure includes circuits and methods for power amplifiers. In one embodiment, a main and peaking amplifier receive dynamic power supply voltages to operate an RF power amplifier in a high efficiency range for a particular output voltage. The power supply voltages may be changed based on an output voltage so that the power amplifier operates within a high efficiency plateau. In one embodiment, different discrete power supply voltage levels are used for different output voltage ranges. In another embodiment, a continuous time varying power supply voltage is provided as the power supply voltage. A dynamic supply voltage may be generated having a lower frequency than a signal path of the power amplifier.

Abstract: A method of canceling nonlinear distortions in pulse width modulated signals includes receiving an input signal. A first signal that is the modulated input signal is generated. The first signal has quantized levels representing the input signal. A pulse width modulated (PWM) sequence that is representative of the first signal is generated. A second signal that is the PWM sequence mixed with a carrier signal is generated. An error signal is generated in response to the first signal and modeled from the second signal. The error signal is added to the input signal.

Abstract: A method for transmitting radio frequency (RF) signals is provided. In-phase (I) and quadrature (Q) signals are received and filtered using sigma-delta modulation. I and Q pulse width modulation signals are generated from the filtered I and Q signals and interleaved so as to generate a time-interleaved signal. The time-interleaved signal is then amplified to generate the RF signals.

Abstract: A radio frequency (RF) transmitter is provided. The RF transmitter includes first and second drivers that are configured to receive first and second sets of complementary RF signals. Restoration circuits are coupled to the first and second drivers, and a bridge circuit is coupled to the first and second restoration circuits. By having the restoration circuits and the bridge circuit, a common mode impedance and a differential impedance can be provided, where the common mode impedance is lower than the differential impedance.

Abstract: A method for generating an amplified radio frequency (RF) signal is provided. In-phase (I) and quadrature (Q) signals are received and interleaved so as to generate a time-interleaved signal. Delayed time-interleaved signals are then generated from the time interleaved signal, and each of the delayed time-interleaved signals is amplified so as to generate a plurality of amplified signals. The amplified signals are then combined with a transformer, where the delayed time-interleaved signals are arranged to generate a filter response with the transformer.

Abstract: A method is provided. An input signal is received, and a noise-shaped signal is generated from the input signal. The noise-shaped signal is formed from a plurality of noise-shaping levels. A pulse stream is generated from the noise-shaped signal over a plurality of periods, where each period has a plurality of frames. The pulse stream also includes a plurality of pulse sets, where each pulse set is associated with at least one of the noise-shaping levels, and, for each pulse set having a total pulse width for its period that is less than its period and greater than zero, each pulse set includes at least one pulse in each frame for its period.

Abstract: A method is provided. A first enable signal is asserted so as to enable a first driver, where the first driver has a first output and a first parasitic capacitance. A second enable signal is asserted so as to enable a second driver, where the second driver has a second output and a second parasitic capacitance. The first and second outputs are coupled together by a switching network when the second driver is enabled. Pulses from complementary first and second radio frequency (RF) signals are applied to the first driver, where there is a first set of free-fly intervals between consecutive pulses from the first and second RF signals, and pulses from complementary third and fourth RF signals are applied to the second driver, wherein there is a second set of free-fly interval between consecutive pulses from the third and fourth RF signals.

Abstract: A method is provided. A first enable signal is asserted so as to enable a first driver, where the first driver has a first output and a first parasitic capacitance. A second enable signal is asserted so as to enable a second driver, where the second driver has a second output and a second parasitic capacitance. The first and second outputs are coupled together by a switching network when the second driver is enabled. Pulses from complementary first and second radio frequency (RF) signals are applied to the first driver, where there is a first set of free-fly intervals between consecutive pulses from the first and second RF signals, and pulses from complementary third and fourth RF signals are applied to the second driver, wherein there is a second set of free-fly interval between consecutive pulses from the third and fourth RF signals.

Abstract: A radio frequency (RF) transmitter is provided. The RF transmitter includes first and second drivers that are configured to receive first and second sets of complementary RF signals. Restoration circuits are coupled to the first and second drivers, and a bridge circuit is coupled to the first and second restoration circuits. By having the restoration circuits and the bridge circuit, a common mode impedance and a differential impedance can be provided, where the common mode impedance is lower than the differential impedance.

Abstract: A method is provided. A noise shaped signal having a plurality of instants is generated with each instant being associated with at least one of a plurality of output levels. A next phase is selected for each instant, where each next phase is a circularly shifted phase based at least in part on a previous phase for the associated output level for its instant. A plurality of PWM signals is then generated using the phase for each instant, and an amplified signal is generated from the plurality of PWM signals.

Abstract: A method for transmitting radio frequency (RF) signals is provided. In-phase (I) and quadrature (Q) signals are received and filtered using sigma-delta modulation. I and Q pulse width modulation signals are generated from the filtered I and Q signals and interleaved so as to generate a time-interleaved signal. The time-interleaved signal is then amplified to generate the RF signals.

Abstract: A method for generating an amplified radio frequency (RF) signal is provided. In-phase (I) and quadrature (Q) signals are received and interleaved so as to generate a time-interleaved signal. Delayed time-interleaved signals are then generated from the time interleaved signal, and each of the delayed time-interleaved signals is amplified so as to generate a plurality of amplified signals. The amplified signals are then combined with a transformer, where the delayed time-interleaved signals are arranged to generate a filter response with the transformer.

Abstract: A method is provided. A noise shaped signal having a plurality of instants is generated with each instant being associated with at least one of a plurality of output levels. A next phase is selected for each instant, where each next phase is a circularly shifted phase based at least in part on a previous phase for the associated output level for its instant. A plurality of PWM signals is then generated using the phase for each instant, and an amplified signal is generated from the plurality of PWM signals.

Abstract: A class D power amplifier (PA) is provided. The PA generally comprises a driver, output capacitor, a matching network, and a cancellation circuit. The driver has an input, an output, and a parasitic capacitance, and the input of the driver is configured to receive complementary first and second radio frequency (RF) signals, where there is a free-fly interval between consecutive pulses from the first and second RF signals. The output capacitor and cancellation circuit are each coupled to the output of the driver such that the cancellation circuit provides harmonic restoration at least during the free-fly interval, and the matching network is coupled to the output capacitor.

Abstract: A class D power amplifier (PA) is provided. The PA generally comprises a driver, output capacitor, a matching network, and a cancellation circuit. The driver has an input, an output, and a parasitic capacitance, and the input of the driver is configured to receive complementary first and second radio frequency (RF) signals, where there is a free-fly interval between consecutive pulses from the first and second RF signals. The output capacitor and cancellation circuit are each coupled to the output of the driver such that the cancellation circuit provides harmonic restoration at least during the free-fly interval, and the matching network is coupled to the output capacitor.

Abstract: Systems and methods may be provided for a LINC system having a level-shifting LINC amplifier. The systems and methods may include a dynamic power supply that is adjustable to provide at least a first voltage supply level and a second voltage supply level higher than the first voltage supply level; a first power amplifier that amplifies a first component signal to generate a first amplified signal; a second power amplifier that amplifiers a second component signal to generate a second amplified signal, where the first component signal and the second component signal are components of an original signal, where the first component signal and the second component signal each have a constant envelope, and where the original signal has a non-constant envelope, and where the first and second power amplifiers are biased at the first voltage supply level or the second voltage supply level based upon an analysis of an amplitude of the original signal.