摘要:
A power amplifying apparatus includes a high-speed low pass filter which inputs an envelope signal included in a transmission signal therein, a low-speed low pass filter which inputs the envelope signal therein, a determination unit which inputs the envelope signal therein and determines rising or falling of the envelope signal, a selecting unit which selects one of the high-speed low pass filter and the low-speed low pass filter according to a determined result of the determination unit, and a voltage supply unit which generates a voltage based on a signal input according to a selection by the selecting unit and supplies the voltage to a power amplifier which inputs the transmission signal therein so as to amplify a power of the transmission signal.
摘要:
A disclosed transmission device includes a voltage control signal generating unit configured to generate a first voltage control signal from a transmission signal, an amplifier configured to amplify the transmission signal in response to the first voltage control signal, a first timing adjusting unit configured to adjust a control timing for the first voltage control signal, and a control timing setting unit configured to set the control timing adjusted by the first timing adjusting unit based on the output signal from the amplifier and the transmission signal.
摘要:
A technique wherein when signals, the modulation schemes of which are different, are to be combined, performing the peak suppression using amounts of the respective modulation schemes can effectively reduce the PAPR of a resulting combined signal. A peak suppressing method for use in a peak suppressing circuit, which combines input signals of different modulation schemes in a time domain to provide a combined signal, comprises detecting, as a peak, that portion of the combined signal which excesses a threshold value to generate a peak signal in accordance with the peak; converting the peak signal into a frequency domain signal and then dividing it into signals originating from the input signals to use these input-signal-originated signals as respective suppression signals; and adding, to the input signals, the suppression signals having different suppression amounts for the respective modulation schemes, thereby performing the peak suppression.
摘要:
A predistortion apparatus for compensating for a distortion arising from a non linear property in input to output characteristics of an amplifier, by processing calculation of a plurality of coefficients for a plurality of power series defining the predistortion characteristics for a plurality of power ranges, respectively, the predistortion apparatus includes: a coefficient update unit for setting and updating coefficients of the power series to provide the predistortion characteristics for the plurality of power ranges in accordance with a comparison between the input and output of the amplifier; and a determination unit for determining at least one threshold value defining the plurality of power ranges by shifting the threshold value and operating the coefficient update unit for updating the coefficients for each of the power series corresponding to each of the power ranges defined by the shifted threshold value.
摘要:
A wireless apparatus includes: an A/D converter which samples an in-phase signal component and a quadrature signal component from a quadrature-modulated signal of analog form alternately; a digital quadrature demodulation unit which applies digital quadrature demodulation to an output signal of the A/D converter and outputs an in-phase signal and a quadrature signal; and an error detection unit which, based on the in-phase and quadrature signals output from the digital quadrature demodulation unit, detects a time difference error between the sample timing of the in-phase signal component and the sample timing of the quadrature signal component.
摘要:
A predistortion apparatus for compensating for a distortion arising from a non linear property in input to output characteristics of an amplifier, by processing calculation of a plurality of coefficients for a plurality of power series defining the predistortion characteristics for a plurality of power ranges, respectively, the predistortion apparatus includes: a coefficient update unit for setting and updating coefficients of the power series to provide the predistortion characteristics for the plurality of power ranges in accordance with a comparison between the input and output of the amplifier; and a determination unit for determining at least one threshold value defining the plurality of power ranges by shifting the threshold value and operating the coefficient update unit for updating the coefficients for each of the power series corresponding to each of the power ranges defined by the shifted threshold value.
摘要:
A distortion compensation apparatus includes a distortion compensation unit that performs distortion compensation processing on a transmission signal by a series operation, a coefficient update unit that updates a group of series operation coefficients used for the series operation based on a feedback signal of transmission signal output that is output after power amplification processing is performed on output of the distortion compensation unit and the transmission signal, an initial coefficient memory that stores the groups of series operation coefficients that become initial values for coefficient update processing by the coefficient update unit, and a power fluctuation detection unit that detects a power fluctuation of the transmission signal and, when the power fluctuation is detected, reads the groups of series operation coefficients from the initial coefficient memory and provides the groups of series operation coefficients to the coefficient update unit.
摘要:
A distortion correction control apparatus is for compensating for a burst distortion of a transmission amplifier caused by a burst of an input signal of a transmission target. The apparatus includes a generation unit that generates a distortion correction coefficient having reverse characteristics to the foregoing burst distortion; a unit that multiplies the distortion correction coefficient output from the generation unit by the input signal or adds the distortion correction coefficient output from the generation unit to the input signal, upon reception of burst information notifying of switching between presence and absence of the input signal; and an update unit that updates, based on the input signal and a branch signal fed back as an output signal of the transmission amplifier, parameters of functions used for adaptively generating the distortion correction coefficient, and that inputs the updated parameters to the generation unit.
摘要:
A distortion compensating apparatus includes a processing circuit that calculates each of a plurality of series operation coefficient pairs based on a transmission signal and a feedback signal of an output from an amplifying circuit performing power amplification of the transmission signal, executes a series operation process with respect to the transmission signal based on the plurality of the series operation coefficient pairs as a distortion compensation of the transmission signal, and inputs a result of the series operation process to the amplifying circuit performing the power amplification, and a selecting unit that, on the basis of power of the transmission signal, selects the series operation process to be executed corresponding to one of the plurality of series operation coefficient pairs, or selects one of the plurality of series operation coefficient pairs to be used in the series operation process to be executed.
摘要:
A power amplifier apparatus that includes a processor that performs a first distortion compensation processing on an input signal using a distortion compensation coefficient to obtain a first signal and an amplifier that amplifies the first signal. The processor performs a second distortion compensation processing the amplified signal using the distortion compensation coefficient to obtain a second signal and updates the distortion compensation coefficient to enable convergence between the first signal and the second signal.