Abstract: System including a dual-fed antenna element is designed to present 2×2 port impedances that guarantee high efficiency operation of the main- and auxiliary transistors at peak- and backed off power. The proposed solution eliminates the need for lossy power combining, such as PCB based circuit combining or impedance matching networks between the antenna element and the main- and auxiliary amplifiers. The power from the main- and auxiliary transistors are combined at the circuit level by the antenna element.

Abstract: There is provided a radio transceiver device. The radio transceiver device comprises an antenna. The radio transceiver device further comprises a signal processing module. The radio transceiver device further comprises a receiver chain configured to receive a first signal. The receiver chain extends from the antenna to the signal processing module and at least comprises an analog-to-digital converter (ADC), and is thereby configured to receive a first signal from the antenna and provide the first signal to the signal processing module after application of analog-to-digital conversion in the ADC to the first signal. The radio transceiver device further comprises a transmitter chain. The transmitter chain extends from the signal processing module to the antenna and at least comprises a digital-to-analog converter (DAC), and is thereby configured to receive a second signal from the signal processing module and provide the second signal to the antenna after application of digital-to-analog conversion in the DAC.

Abstract: A linearization device (380) is disclosed, which is configured to determine pre-distortion parameters associated with a plurality of non-linear amplifiers (331, 332, 333, 334), each associated with a non-linear amplifier characteristic. The linearization device comprises determination circuitry (383), a first port (381) and a second port (382). The first port is configured to receive a plurality of channel coefficients indicative of channel characteristics of a plurality of communication paths (391, 392, 393, 394) between the plurality of non-linear amplifiers and a transmit observation receiver (370). The second port is configured to receive, from the transmit observation receiver, a sum of transmission signals generated by the plurality of non-linear amplifiers and transferred over the plurality of communication paths.

Abstract: A linearization device (380) is disclosed, which is configured to determine pre-distortion parameters associated with a plurality of non-linear amplifiers (331, 332, 333, 334). Each of the non-linear amplifiers is associated with one of a plurality of transmit antenna elements and with a non-linear transfer function defining an output of the non-linear amplifier based on an input of the non-linear amplifier and based on a reflection signal for the non-linear amplifier, resulting from mutual couplings among the plurality of transmit antenna elements. The linearization device comprises a first port (381), a second port (382), and determination circuitry (383). The first port is configured to receive a plurality of channel coefficients indicative of channel characteristics of a plurality of communication paths between the plurality of non-linear amplifiers and two or more transmit observation receivers (370, 371, 372).

Abstract: System including a dual-fed antenna element is designed to present 2×2 port impedances that guarantee high efficiency operation of the main- and auxiliary transistors at peak- and backed off power. The proposed solution eliminates the need for lossy power combining, such as PCB based circuit combining or impedance matching networks between the antenna element and the main- and auxiliary amplifiers.

Abstract: A linearization device (380) is disclosed, which is configured to determine pre-distortion parameters associated with a plurality of non-linear amplifiers (331, 332, 333, 334), each associated with a non-linear amplifier characteristic. The linearization device comprises determination circuitry (383), a first port (381) and a second port (382). The first port is configured to receive a plurality of channel coefficients indicative of channel characteristics of a plurality of communication paths (391, 392, 393, 394) between the plurality of non-linear amplifiers and a transmit observation receiver (370). The second port is configured to receive, from the transmit observation receiver, a sum of transmission signals generated by the plurality of non-linear amplifiers and transferred over the plurality of communication paths.

Abstract: The disclosure relates to devices, methods, and computer programs in mobile communications in order to reduce signal distortions. Specifically, it relates to a transmitter system which comprises a plurality of signal paths. Each signal path is associated with an input transmission signal. Each signal path comprises an analog portion of the signal path. Each 5 signal path comprises a Dual-Input Digital Predistortion, DI DPD, module. The DI DPD is configured to provide a predistorted input transmission signal to the analog portion in response to a received Crosstalk and Mismatch, CTM, signal and the input transmission signal. The transmitter system further comprises one or more CTM modules configured to receive one or more input transmission signals. The CTM module comprises to separately generate for 10 each DI DPD module the CTM signal, where said CTM signals represent CTM distortions caused by one or more output transmission signals of each said analog portion.

Abstract: The disclosure relates to devices, methods, and computer programs in mobile communications in order to reduce signal distortions. Specifically, it relates to a transmitter system which comprises a plurality of signal paths. Each signal path is associated with an input transmission signal. Each signal path comprises an analogue portion of the signal path. Each 5 signal path comprises a Dual-Input Digital Predistortion, DI DPD, module. The DI DPD is configured to provide a predistorted input transmission signal to the analogue portion in response to a received Crosstalk and Mismatch, CTM, signal and the input transmission signal. The transmitter system further comprises one or more CTM modules configured to receive one or more input transmission signals. The CTM module comprises to separately generate for 10 each DI DPD module the CTM signal, where said CTM signals represent CTM distortions caused by one or more output transmission signals of each said analogue portion.

Abstract: It is provided an amplifier arrangement for optimizing efficiency at a peak power level and a back-off power level ?. The amplifier arrangement comprises an input power splitter dividing an input signal into a first signal having a power Pm and a second signal having a power Pa, a main transistor operating in a class-B like mode receiving the first signal, an auxiliary transistor operating in a class-C mode receiving the second signal. The received first and second signals have a phase offset value ?, wherein ??<?<?. The amplifier arrangement further comprises a combining network.

Abstract: It is provided an amplifier arrangement for optimizing efficiency at a peak power level and a back-off power level ?. The amplifier arrangement comprises an input power splitter dividing an input signal into a first signal having a power Pm and a second signal having a power Pa, a main transistor operating in a class-B like mode receiving the first signal, an auxiliary transistor operating in a class-C mode receiving the second signal. The received first and second signals have a phase offset value ?, wherein ??<?<?. The amplifier arrangement further comprises a combining network.

Abstract: An amplifier arrangement for optimising efficiency at a peak power level and a back-off power level comprises a main power amplifier provided in a main branch for receiving a first signal, the main power amplifier being configured to operate in a class-B mode of operation. An auxiliary power amplifier is provided in an auxiliary branch for receiving a second signal, the auxiliary power amplifier being configured to operate in a class-C mode of operation. The main power amplifier and the auxiliary power amplifier are substantially matched in size. The first signal and the second signal have a phase offset value ? that is selected in relation to a particular back-off power level ? of operation, wherein 0<?<180°. A combining network is configured to couple the output signals of the main and auxiliary amplifiers to an output node of the amplifier arrangement such that the output of the auxiliary power amplifier load modulates the output of the main power amplifier.

Abstract: The present disclosure provides a power amplifier comprising a main amplifier and an auxiliary amplifier. The power amplifier is configured to deliver an output power Pout. A First Efficiency Peak (FEP) is defined as a first efficiency peak in the power ratio Pout to Poutmax. Poutmax is a maximum power output of the power amplifier and PFEP defines a power ratio at the FEP. The main amplifier is configured to be biased by a main amplifier bias Vds,m that is substantially equal to an auxiliary amplifier bias Vds,a times xb with xb being a main amplifier output current in relation to the maximum current through the main amplifier when Pout equals PFEP. The impedances of a load and a main amplifier transmission line are arranged to be substantially equal. A corresponding method and a node in a wireless communication system comprising the power amplifier are also disclosed.

Abstract: The present disclosure provides a power amplifier comprising a main amplifier and an auxiliary amplifier. The power amplifier is configured to deliver an output power Pout. A First Efficiency Peak (FEP) is defined as a first efficiency peak in the power ratio Pout to Poutmax. Poutmax is a maximum power output of the power amplifier and PFEP defines a power ratio at the FEP. The main amplifier is configured to be biased by a main amplifier bias Vds,m that is substantially equal to an auxiliary amplifier bias Vds,a times xb with xb being a main amplifier output current in relation to the maximum current through the main amplifier when Pout equals PFEP. The impedances of a load and a main amplifier transmission line are arranged to be substantially equal. A corresponding method and a node in a wireless communication system comprising the power amplifier are also disclosed.

Abstract: The present invention use the properties of a TDD-transmission on a specific mixer in such a manner that in the transmit mode a first RF signal is amplified in the mixer with an amplification factor greater than, or equal to, or less than one, and in the receive mode the received RF signal is mixed with a second RF signal.