An example method for facilitating a high power efficient amplifier through digital pre-distortion (DPD) in cable network environments is provided and includes receiving a first signal and a second signal at a DPD coefficient finder in an amplifier module of a cable modem, the second signal including transformations of the first signal from distortions due to channel effects and amplifier nonlinearity, synchronizing the first signal and the second signal, removing the channel effects, computing a first vector representing an inverse of the nonlinearity of the amplifier, computing a second vector representing an inverse of certain channel effects and providing DPD coefficients to a DPD actuator, the DPD coefficients including the first vector and the second vector, the DPD actuator predistorting an input signal to the amplifier module with the DPD coefficients, such that an output signal from the amplifier module retains linearity relative to the input signal.

The present invention is a rectangular waveguide providing amplification of an electromagnetic wave via interaction with an electron beam in a linear interaction channel where the electron beam enters the waveguide at a first curved part of the waveguide, traverses the linear interaction channel and exits the waveguide at a second curved part of the waveguide.

The present invention is a rectangular waveguide providing amplification of an electromagnetic wave via interaction with an electron beam in a linear interaction channel where the electron beam enters the waveguide at a first curved part of the waveguide, traverses the linear interaction channel and exits the waveguide at a second curved part of the waveguide.

Exemplary embodiments are related to method and devices for calibration a radio-frequency (RF) transceiver. A method may include calibrating an RF device by calculating input voltage values and bias voltage values of a power amplifier for each desired output voltage value of the power amplifier to generate a desired compression point. The method may also include applying digital pre-distortion (DPD) values to the input voltage of the power amplifier, and measuring a value of the output voltage after applying the DPD values.

Exemplary embodiments are related to method and devices for calibration a radio-frequency (RF) transceiver. A method may include calibrating an RF device by calculating input voltage values and bias voltage values of a power amplifier for each desired output voltage value of the power amplifier to generate a desired compression point. The method may also include applying digital pre-distortion (DPD) values to the input voltage of the power amplifier, and measuring a value of the output voltage after applying the DPD values.

Various methods and circuital arrangements for biasing one or more gates of stacked transistors of an amplifier are possible where the amplifier is configured to operate in at least an active mode and a standby mode. Circuital arrangements can reduce bias circuit standby current during operation in the standby mode while allowing a quick recovery to normal operating conditions of the amplifier. Biasing an input transistor of the stacked transistors can be obtained by using a replica stack circuit.

Various methods and circuital arrangements for biasing one or more gates of stacked transistors of an amplifier are possible where the amplifier is configured to operate in at least an active mode and a standby mode. Circuital arrangements can reduce bias circuit standby current during operation in the standby mode while allowing a quick recovery to normal operating conditions of the amplifier. Biasing an input transistor of the stacked transistors can be obtained by using a replica stack circuit.

The invention relates to a broadband high power amplifier that comprises a signal input adapted to receive an input signal, at least one amplifier stage adapted to amplify the received input signal, a signal output adapted to output the signal amplified by the at least one amplifier stage as an output signal, a monitoring unit adapted to monitor signal characteristics of the input signal and the output signal and a control unit adapted to operate the at least one amplifier stage at an optimal operating point depending on the current signal characteristics monitored by said monitoring unit.

A generator and method for tuning the generator are disclosed. The method includes setting the frequency of power applied by the generator to a current best frequency and sensing a characteristic of the power applied by the generator. A current best error based upon the characteristic of the power is determined, and the frequency of the power at the current best frequency is maintained for a main-time-period. The frequency of the power is then changed to a probe frequency and maintained at the probe frequency for a probe-time-period, which is less than the main-time-period. The current best frequency is set to the probe frequency if the error at the probe frequency is less than the error at the current best frequency.

A generator and method for tuning the generator are disclosed. The method includes setting the frequency of power applied by the generator to a current best frequency and sensing a characteristic of the power applied by the generator. A current best error based upon the characteristic of the power is determined, and the frequency of the power at the current best frequency is maintained for a main-time-period. The frequency of the power is then changed to a probe frequency and maintained at the probe frequency for a probe-time-period, which is less than the main-time-period. The current best frequency is set to the probe frequency if the error at the probe frequency is less than the error at the current best frequency.