Abstract: A carrier leak compensating device (2) for adding compensation values to a received transmission signal, an analog quadrature modulator (4), a feedback device (5-7) for receiving and quadrature-detecting part of an output signal of the analog quadrature modulator and outputting a feedback signal in which the frequency of each carrier signal is the same as in the transmission signal, a carrier leak detecting device (800) for detecting an I-phase carrier leak and a Q-phase carrier leak on the basis of the difference between cumulative addition values of an amplitude/phase-adjusted feedback signal and the transmission signal, and a carrier leak compensation value controller (9) for updating the compensation values on the basis of the detected carrier leak. The number of samples for the amplitude/phase detection may be smaller than the number of cumulative addition samples.

Abstract: A transmitter suppresses peak power occurring in a transmission signal. The transmitter generates peak suppression signals for suppressing the peak power in the transmission signal respectively, synthesizes the peak suppression signals generated, and subtracts a signal as a synthesis result from the transmission signal.

Abstract: A transmitter suppresses a peak level of a multi-carrier signal produced by synthesizing a plurality of carrier signals. Specifically, a peak level suppression signal for a multi-carrier signal is generated. The generated peak level suppression signal is adjusted in accordance with the levels of respective carriers constituting the multi-carrier signal. And, the adjusted peak level suppression signal for each carrier is subtracted from an input signal, thereby generating a multi-carrier signal whose peak level is suppressed.

Abstract: A transmitter, which may suppress peak power in a transmission signal, effectively suppresses peak power occurring in a transmission signal. In a transmitter that may suppress peak power in a transmission signal, a plurality of peak-suppression-signal generating means generate peak suppression signals for suppressing the peak power in the transmission signal respectively, peak-suppression-signal synthesizing means synthesizes peak suppression signals generated by the plurality of peak-suppression-signal generating means, and subtraction means subtracts a signal as a synthesis result given by the peak-suppression-signal synthesizing means from the transmission signal.

Abstract: It is intended to compensate for a carrier leak for any carrier arrangement. There are provided a carrier leak compensating means 2 for adding compensation values to a received transmission signal, an analog quadrature modulator 4, feedback means 5-7 for receiving and quadrature-detecting part of an output signal of the analog quadrature modulator and outputting a feedback signal in which the frequency of each carrier signal is the same as in the transmission signal, a carrier leak detecting means 800 for detecting an I-phase carrier leak and a Q-phase carrier leak on the basis of the difference between cumulative addition values of an amplitude/phase-adjusted feedback signal and the transmission signal, and a carrier leak compensation value control means 9 for updating the compensation values on the basis of the detected carrier leak. The number of samples for the amplitude/phase detection may be smaller than the number of cumulative addition samples.

Abstract: In a transmitter that suppresses the peak level of a multi-carrier signal produced by synthesizing a plurality of carrier signals, high signal quality is maintained for any transmission signal pattern, for example. In a peak power suppression means shown in the drawings, suppression signal generation means 7 to 18 generate a peak level suppression signal having a level according to levels of respective carrier signals for frequencies of the respective carrier signals contained in the multi-carrier signal. Suppression signal subtraction means 19, 20 subtract, from the multi-carrier signal, the peak level suppression signal generated by the suppression signal generation means 7 to 18.

Abstract: There is disclosed a synchronous circuit and a receiver in which a long code for use in communication can be determined in a short time, and circuit scale can be reduced. Upon receiving input of a data stop signal from a control unit, a matched filter continues to hold the signal held at the time, performs a product sum operation of a spreading code successively inputted from a spreading code generator and the held signal, and successively outputs correlation signals in the synchronous circuit and the receiver.