Abstract: A multicarrier transmitting method that includes inputting n input signals, generating carriers corresponding to the n input signals, modulating the carriers into n modulated signals and generating at least one additional signal having a frequency outside band of the n modulated signals. The method also includes adjusting a level and a phase of the generated additional signal, outputting a multiplexed signal by adding up the n modulated signals and the adjusted additional signal, amplifying the multiplexed signal, and then removing the additional signal. The level and the phase of the additional signal are adjusted such that, after predicting a change of a composite vector of the n modulated signals based on an amplitude and a phase of the n carriers, a composite vector obtained after an adding operation can be lower than that before the adding operation when an absolute value of a prediction result exceeds a predetermined level.

Abstract: A balun design incorporating the functions of a splitter (combiner) which can be employed in a high power amplifier circuit configuration. The balun is formed of a dielectric multilayer board with conductor patterns on each conductor pattern layer. The balun includes the propagation of a half of an input signal to an in-phase output terminal, and also propagating a fourth of the input signal to first and second opposite-phase output terminals, the signal propagated to the first and second opposite-phase output terminals lagging 180 degrees behind the signal propagated to the in-phase output terminal. The balun provides the output signals at the first and second opposite-phase output terminals 180° out of phase employing through holes in the main line and coupling lines for promoting electromagnetic coupling therebetween.

Abstract: A high power amplifier has a first balun propagating a half of an input signal to an in-phase output terminal, and also propagating a fourth of the input signal to first and second opposite-phase output terminals, the signal propagated to the first and second opposite-phase output terminals lagging 180 degrees behind the signal propagated to the in-phase output terminal; first and second power amplifier circuits connected to the first and second opposite-phase output terminals of the first balun and having the same characteristics; a third power amplifier circuit connected to the in-phase output terminal of the first balun and having output power substantially twice as much as the output power of the first or second power amplifier circuit; and a second balun having first and second opposite-phase input terminals for receiving the outputs of the first and second power amplifier circuits, having an in-phase input terminal for receiving the output of the third power amplifier circuit, combining the outputs of t

Abstract: To reduce the size of a multi-carrier transmitter circuit for a mobile communication base station, by suppressing instantaneous peak output power to a small value with respect to a wide-band signal of a few MHz to tens of MHz so that the peak factor of a multi-carrier signal is reduced.

Abstract: A balun design incorporating the functions of a splitter (combiner) which can be employed in a high power amplifier circuit configuration. The balun is formed of a dielectric multilayer board with conductor patterns on each conductor pattern layer. The balun includes the propagation of a half of an input signal to an in-phase output terminal, and also propagating a fourth of the input signal to first and second opposite-phase output terminals, the signal propagated to the first and second opposite-phase output terminals lagging 180 degrees behind the signal propagated to the in-phase output terminal. The balun provides the output signals at the first and second opposite-phase output terminals 180° out of phase employing through holes in the main line and coupling lines for promoting electromagnetic coupling therebetween.

Abstract: A feedforward amplifier includes a power divider for dividing the input signal into first and second signals. The first signal is processed in a first path that includes, in sequence, a first vector adjuster, a main amplifier, a directional coupler and a delay circuit. The second signal is delayed in a second path that includes, in sequence, another delay circuit, a first power combiner and an auxiliary amplifier block. The first power combiner combines the first signal, by way of a coupling port from the directional coupler, with the second signal to provide a combined signal into the auxiliary amplifier block. The auxiliary amplifier block further divides the second signal into two divided signals, each having a respective non-overlapping frequency band. The two divided signals are respectively vector adjusted, amplified, and then recombined. The recombined signal is then recombined with the processed signal in the first path to provide the desired output signal.

Abstract: According to the configuration the present power splitter, it is possible to reduce the characteristic impedance of a transmission line constituting a directional coupler by setting the impedance of a first terminal pair constituted of an input port 7a and a second output port 7d of a 6-dB branch-line-shaped directional coupler 7 to a value smaller than a reference impedance Z0 (50 &OHgr; in general) and setting the impedance of a second terminal pair constituted of an isolation port 7b and a first output port 7c of the directional coupler 7 to Z0. Therefore, it is possible to increase the number of splits and reduce loss, as compared with conventional cases.

Abstract: A high power amplifier has a first balun propagating a half of an input signal to an in-phase output terminal, and also propagating a fourth of the input signal to first and second opposite-phase output terminals, the signal propagated to the first and second opposite-phase output terminals lagging 180 degrees behind the signal propagated to the in-phase output terminal; first and second power amplifier circuits connected to the first and second opposite-phase output terminals of the first balun and having the same characteristics; a third power amplifier circuit connected to the in-phase output terminal of the first balun and having output power substantially twice as much as the output power of the first or second power amplifier circuit; and a second balun having first and second opposite-phase input terminals for receiving the outputs of the first and second power amplifier circuits, having an in-phase input terminal for receiving the output of the third power amplifier circuit, combining the outputs of t

Abstract: A feed forward amplifier comprises a main amplifier 10 composed of a plurality of power amplifiers 8 and 9 combined in parallel. In addition to the plurality of power amplifiers, this feed forward amplifier includes a distortion detecting amplifier 25 for detecting the distortion components, having a distortion characteristic in a predetermined relationship with the distortion characteristic of the main amplifier. It also omits a distortion detecting power combiner 23 otherwise located after a main amplifier 10 and locates a delay circuit 21 before the main amplifier 10 to reduce losses occurring after the main amplifier 10 to improve the efficiency of the entire feed forward amplifier.