Abstract: A data calculator repeatedly calculates electric power of a delayed transmission signal and a multiplication value of a complex conjugate of the delayed transmission signal and a feedback signal. A memory stores, for each delayed electric power address corresponding to the electric power, a first total value that is the total of electric power of the delayed transmission signal and a second total value that is the total of the multiplication value. A range adjuster adjusts the upper limit of a determination reference range according to the maximum reference address. When a determiner determines that the number of repeats of the data calculator is sufficient based on the determination reference range, a vector calculator calculates a distortion correction vector based on a distortion vector calculated from the ratio between the first total value and the second total value. An updater updates the distortion correction vector stored in a look-up table based on the distortion correction vector.

Abstract: A data calculator repeatedly calculates electric power of a delayed transmission signal and a multiplication value of a complex conjugate of the delayed transmission signal and a feedback signal. A memory stores, for each delayed electric power address corresponding to the electric power, a first total value that is the total of electric power of the delayed transmission signal and a second total value that is the total of the multiplication value. A range adjuster adjusts the upper limit of a determination reference range according to the maximum reference address. When a determiner determines that the number of repeats of the data calculator is sufficient based on the determination reference range, a vector calculator calculates a distortion correction vector based on a distortion vector calculated from the ratio between the first total value and the second total value. An updater updates the distortion correction vector stored in a look-up table based on the distortion correction vector.

Abstract: A phase comparator detects time lag or time lead of the phase of a data signal with respect to a reproduced clock signal from a first digital VCO. A random walk filter measures a difference between number of lags and number of leads, controls the first digital VCO to shift the phase of the reproduced clock signal in a direction to cancel the difference when the absolute value of the difference reaches a predetermined value, and resets the measurement result to restart the measurement. A phase comparator detects the phase difference between reproduced clock signals from the first digital VCO and a second digital VCO and notifies it to the random walk filter. While the amount of the notified phase difference is being a predetermined amount, the random walk filter neither resets the measurement result nor shifts the phase of the reproduced clock signal from the first digital VCO.

Abstract: A wireless communication apparatus performs fast control even on a large phase rotation of a received signal to synchronize the frequency of a received signal with a specified frequency. A symbol-phase-difference detector detects an intersymbol phase difference of an input signal demodulated by a quadrature demodulator. When a minute-phase-error detector detects an intersymbol minute phase error between symbols whose phase difference has been detected by the symbol-phase-error detector, an oversampling/phase-rotational-amount detecting section detects an intersymbol phase rotational amount of the received signal by oversampling the received signal at a rate higher than a symbol rate. A coarse-phase-error detector detects a coarse phase error between symbols whose phase difference has been detected by the oversampling/phase-rotational-amount detecting section. A frequency control amount calculator computes a frequency control amount for the process station to control the frequency of the input signal.

Abstract: A phase comparator detects time lag or time lead of the phase of a data signal with respect to a reproduced clock signal from a first digital VCO. A random walk filter measures a difference between number of lags and number of leads, controls the first digital VCO to shift the phase of the reproduced clock signal in a direction to cancel the difference when the absolute value of the difference reaches a predetermined value, and resets the measurement result to restart the measurement. A phase comparator detects the phase difference between reproduced clock signals from the first digital VCO and a second digital VCO and notifies it to the random walk filter. While the amount of the notified phase difference is being a predetermined amount, the random walk filter neither resets the measurement result nor shifts the phase of the reproduced clock signal from the first digital VCO.

Abstract: A wireless communication apparatus performs fast control even on a large phase rotation of a received signal to synchronize the frequency of a received signal with a specified frequency.