Multi-band power amplification system having enhanced efficiency through elimination of band selection switch. In some embodiments, a power amplification system can include a plurality of power amplifiers (PAs), with each PA being configured to receive and amplify a radio-frequency (RF) signal in a frequency band. The power amplification system can further include an output filter coupled to each of the PAs by a separate output path such that the power amplification system is substantially free of a band selection switch between the plurality of PAs and their corresponding output filters. Each PA can be further configured to drive approximately a characteristic load impedance of the corresponding output filter by, for example, the PA being operated with a high-voltage (HV) supply.

Circuits and methods for 2G amplification using 3G/4G linear path combination. In some embodiments, a front-end architecture can include a first amplification path and a second amplification path, with each being configured to amplify a 3G/4G signal, and the first amplification path including a phase shifting circuit. The front-end architecture can further include a splitter configured to receive a 2G signal and split the 2G signal into the first and second amplification paths, and a combiner configured to combine amplified 2G signals from the first and second amplification paths into a common output path. The front-end architecture can further include an impedance transformer implemented along the common output path to provide a desired impedance for the combined 2G signal.

A predistortion circuit receives an input polar signal to be transmitted, including an input amplitude signal and an input phase signal. The input polar signal is predistorted using at least one predistortion parameter selected from a lookup table. A phase-and-amplitude modulated radio-frequency signal is generated corresponding to the predistorted polar signal. A copy of the generated radio-frequency signal is provided to a polar receiver. The polar receiver is operated to generate, from the copy of the radio-frequency signal and without information relating to the generated transmit signal, a feedback polar signal including a feedback amplitude signal and a feedback phase signal. The feedback polar signal is compared to the input polar signal, the lookup table is updated in response to the comparison.

A multi-band power amplifier module includes at least one transmission input terminal, at least one power amplifier circuit that receives a first transmission signal and a second transmission signal through the at least one transmission input terminal, a first filter circuit that allows the first transmission signal to pass therethrough, a second filter circuit that allows the second transmission signal to pass therethrough, at least one transmission output terminal through which the first and second transmission signals output from the first and second filter circuits are output, a transmission output switch that outputs each of the first and second transmission signals output from the at least one power amplifier circuit to the first filter circuit or the second filter circuit, and a first tuning circuit that adjusts impedance matching between the at least one power amplifier circuit and the at least one transmission output terminal.

A predistortion circuit receives an input polar signal to be transmitted, including an input amplitude signal and an input phase signal. The input polar signal is predistorted using at least one predistortion parameter selected from a lookup table. A phase-and-amplitude modulated radio-frequency signal is generated corresponding to the predistorted polar signal. A copy of the generated radio-frequency signal is provided to a polar receiver. The polar receiver is operated to generate, from the copy of the radio-frequency signal and without information relating to the generated transmit signal, a feedback polar signal including a feedback amplitude signal and a feedback phase signal. The feedback polar signal is compared to the input polar signal, the lookup table is updated in response to the comparison.

Reduced power amplifier size through elimination of matching network. In some embodiments, a power amplification system can include a power amplifier (PA) configured to receive and amplify a radio-frequency (RF) signal. The power amplification system can further include a filter coupled to the PA and configured to condition the amplified RF signal. The PA can be further configured to drive approximately a characteristic load impedance of the filter. Such a configuration of the PA can be achieved by operating the PA with a high-voltage supply. Such a power amplification system can allow elimination of a matching network to, for example, reduce loss and device size.

A surface acoustic wave (SAW) filter that receives an aggregate circuit and outputs two or more sub-signals on outputs each of a different frequency band. The sub-signals are amplified by low noise amplifiers and, in one implementation, the amplified sub-signals can be summed. The outputs are connected via a switched passive network so that portions of the sub-signals on the outputs that are not in the selected frequency band are at least partially terminated.

A broadband linear processing system includes a pre-processing module and a set of M linear processors coupled to the pre-processing module, M being an integer greater than 1. The pre-processing module includes a wavefront multiplexer having M input ports and M output ports. The wavefront multiplexer receives M input signals at the M input ports, performs a wavefront multiplexing transform on the M input signals and outputs M narrowband signal streams at the M output ports. The wavefront multiplexing transform has an inverse. Each of the M linear processors receives and processes a corresponding one of the M narrowband signal streams, and outputs a corresponding one of M processed narrowband signal streams.

In a semiconductor device, received signals of different frequency bands are input selectively to low noise amplifiers. A plurality of primary inductors are coupled between differential output nodes of the respective low noise amplifiers. A secondary inductor is provided commonly for the primary inductors, and magnetically coupled to the primary inductors. A demodulator converts a received signal transmitted from one of the primary inductors to the secondary inductor by electromagnetic induction, into a signal of a low frequency.

A wireless communication device includes an amplifier block amplifying a radio frequency (RF) input signal. The amplifier block includes: a first amplification unit and a second amplification unit. The first amplification unit amplifies the RF input signal to generate a first RF amplified signal including a first non-linearity factor and a second RF amplified signal including a second non-linearity factor, and combines the first and second RF signals to generate a third RF amplified signal. The second amplification unit receives and amplifies the third RF amplified signal to output an RF output signal corresponding to the at least one carrier.