Abstract: There is provided a wireless device capable of supporting both of TDD and FDD wireless communications with a simple configuration. The wireless device includes a transmitter that transmits a signal of a first frequency; a DPD receiver that receives signals of the first frequency; a receiver that receives signals of a second frequency; a duplexer having a first filter having passband characteristics in the first frequency band and a second filter having passband characteristics in the second frequency band; and a circulator that splits the signal from the transmitter to output the split signals to the duplexer and the DPD receiver, and outputs a reception signal from the duplexer to the DPD receiver. The duplexer is connected to the circulator on the first filter side and to the receiver on the second filter side, and uses the DPD receiver for FDD and TDD transmission feedback and for TDD reception.

Abstract: There is provided a wireless device capable of supporting both of TDD and FDD wireless communications with a simple configuration. The wireless device includes a transmitter that transmits a signal of a first frequency; a DPD receiver that receives signals of the first frequency; a receiver that receives signals of a second frequency; a duplexer having a first filter having passband characteristics in the first frequency band and a second filter having passband characteristics in the second frequency band; and a circulator that splits the signal from the transmitter to output the split signals to the duplexer and the DPD receiver, and outputs a reception signal from the duplexer to the DPD receiver. The duplexer is connected to the circulator on the first filter side and to the receiver on the second filter side, and uses the DPD receiver for FDD and TDD transmission feedback and for TDD reception.

Abstract: An amplifier capable of lowering an electrical current flowing in a peak amplifier before a carrier amplifier becomes saturated to thereby improve the efficiency of an entirety of the amplifier is provided. The amplifier includes a carrier amplifier circuit having an amplifying element operable in class-AB or class-B, and a plurality of peak amplifier circuits which have amplifying elements operating in class-B or class-C and which are arranged to start an operation in stages in response to an input level. An output of the carrier amplifier circuit and outputs of the peak amplifier circuits are combined together for signal output. One of the peak amplifier circuits which is rendered operative at the lowest input level is smaller in saturation output than the carrier amplifier circuit.

Abstract: An amplifier capable of lowering an electrical current flowing in a peak amplifier before a carrier amplifier becomes saturated to thereby improve the efficiency of an entirety of the amplifier is provided. The amplifier includes a carrier amplifier circuit having an amplifying element operable in class-AB or class-B, and a plurality of peak amplifier circuits which have amplifying elements operating in class-B or class-C and which are arranged to start an operation in stages in response to an input level. An output of the carrier amplifier circuit and outputs of the peak amplifier circuits are combined together for signal output. One of the peak amplifier circuits which is rendered operative at the lowest input level is smaller in saturation output than the carrier amplifier circuit.

Abstract: According to the present invention, there is provided a strain (error) compensation amplifier which realizes miniaturization, loss reduction, and cost reduction. In the strain (error) compensation amplifier, by unifying at least two or more of a power distributor, a first delay unit, a first power synthesizer, a second delay unit, a second power synthesizer, a directional coupler, an isolator and a terminating resistor, the miniaturization, loss reduction, and cost reduction are realized.

Abstract: According to the present invention, there is provided a strain compensation amplifier which realizes miniaturization, loss reduction, and cost reduction.

Abstract: A distortion compensating device comprises a 3 dB coupler having four terminals. The first terminal supplies an input signal to be inputted to an amplifier or is supplied with an input signal from an amplifier. The second terminal is associated with a third-order distortion generator for generating a third-order distortion having an amplitude for canceling out a third-order distortion generated by the amplifier depending on the supplied input signal. The third terminal is associated with a phase adjuster for adjusting the phase of the input signal to set the phase difference between the input signal and the third-order distortion generated by the third-order distortion generator to a phase difference for canceling out the third-order distortion generated by the amplifier.