Matsushita Electric Industrial Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Matsushita Electronics Corporation

Communications Research Laboratory, Ministry of Posts and

Mitsuru Tanabe

Koichiro Tanaka

Noriaki Saito

Yoshiharu Anda

Taiji Akizuki

Kaoru Inoue

Manabu Yanagihara

Yorito Ota

Kazunori Kidera

Toshinobu Matsuno

Junko Iwanaga

Mariko Kifuji

Katsunori Nishii

Kazuo Itoh

Yoshihisa Minami

Mitsuru Maeda

Mitsuru Nishitsuji

Toshiaki Matsui

Teruhito Takeda

Shigeru Kataoka

Yasuko Yamamoto

Daisuke Watanabe

Takaharu Saeki

Kenji Kuniyoshi

Takatoshi Tanaka

Yorito Ohta

Nobumitsu Hirose

A controller switches between modes each having a different connection state of a DC power supply and the capacitor with respect to first and second output points by controlling switches. A generation unit generates a reference wave including at least one carrier wave. The modes are classified into a sustaining mode in which no current is caused to flow to the capacitor, a charging mode in which a current is caused to flow to the capacitor, and a discharging mode in which a current in a direction opposite to that in the charging mode is caused to flow to the capacitor. The controller switches between the sustaining mode and a charging or discharging mode according to the comparison result between a signal wave and the reference wave.

Power converting device, and power conditioner using same

A first bidirectional switch is electrically connected between a first connection point which is a connection point of a first switching element and a second switching element and a second connection point which is a connection point of a seventh switching element and an eighth switching element. A second bidirectional switch is electrically connected between a third connection point which is a connection point of a third switching element and a fourth switching element and a fourth connection point which is a connection point of a fifth switching element and a sixth switching element. A power-converting device is configured to generate an output voltage between a first output point and a second output point.

Power-converting device and power conditioner using the same

The electric vehicular connector includes: a connection terminal block including a primary power transmission terminal to be electrically connected to a first power terminal of a power converter; a plug including a secondary power transmission terminal to be electrically connected to a second power terminal of an inlet of an electric vehicle; a breaker which is connected between the primary power transmission terminal and the secondary power transmission terminal and has a closed state of electrically interconnecting the primary power transmission terminal and the secondary power transmission terminal and an open state of electrically separating the primary power transmission terminal and the secondary power transmission terminal from each other; and a breaker controller configured to set the connector-side breaker in the closed state during a normal state and to set the connector-side breaker in the open state during an abnormal state in which abnormality occurs in the electric vehicle.

Electric vehicular connector and vehicular power supply device

A splitter includes, in parallel between trunk terminals and branch terminals, a signal branching circuit that blocks distributed power and passes a PLC communication signal and a power branching circuit that blocks the communication signal and passes the distributed power. In the signal branching circuit, impedance viewed from the branch terminal side is matched with characteristic impedance of a power line and impedance viewed from the trunk terminal side is higher than impedance viewed from the branch terminal side, in the frequency band of the communication signal. In the power branching circuit, input/output impedance is set to be sufficiently higher than the impedance of the signal branching circuit viewed from the trunk terminal side, in the frequency band of the communication signal.

Splitter

A communication system comprises: a communication apparatus that is configured to transmit communication data, which includes a plurality of known synchronization symbols subjected to spread modulation with a spread code; and a communication apparatus that is configured to perform, when receiving the communication data, processing for detecting a synchronization timing, based on a correlation value between the received communication data and a reference signal. The communication apparatus comprises: a disturbing wave detection part configured to detect a period of a disturbing wave; a communication control part configured to set a transmission period of the synchronization symbol to be integer multiple of the period of the disturbing wave; and a transmission unit configured to transmit the communication data in which the transmission period of the synchronization symbol has been set by the communication control part.

Communication system and communication method

A transmitter providing a wide output control variable width with high efficiency is provided. Saturation mode operation is performed in the vicinity of the maximum transmission power and the input level of a large power amplifier is enlarged and fixed. When the large power amplifier is operated in a saturation state, the amplitude component of a modulation signal is input to an R input terminal in the range responsive to an output power control level and power supply voltage of a power supply terminal is amplitude-modulated, whereby highly efficient polar coordinate modulation is performed. In smaller transmission power, linear mode operation is performed, the input level of the large power amplifier is lessened for operating the large power amplifier in the linear mode, and the power supply voltage of the power supply terminal is made variable in response to the output power control level, whereby transmission power control is performed.

Transmitter apparatus and wireless communication apparatus

A transmitter according to the present invention is a transmitter conforming to the EER method, wherein a modulated signal is separated into phase and amplitude components, and the components are input to the high-frequency input terminal and the power supply voltage terminals of a high-frequency power amplifier. This transmitter comprises an amplitude delay corrector and a phase delay corrector capable of correcting delay time so that the phase and amplitude components are optimally synthesized using two or more stages of saturation-type amplifiers constituting the high-frequency power amplifier. With this configuration, a synthesis error can be reduced in each stage of the saturation-type amplifier, and distortion components in the output waveform can be reduced.

Transmitter

An amplitude component of a modulating signal is detected, band-divided by first and second frequency selecting circuits, and an amplitude component of a high-frequency band is down-converted by a first frequency conversion circuit. An amplitude component selected by the first frequency selecting circuit and an amplitude component selected by the first frequency conversion circuit are amplified by first and second operational amplifiers, and a signal amplified by the second operational amplifier is up-converted by a second frequency conversion circuit to be restored to the initial frequency band. Output amplitudes of the first operational amplifier and a second frequency converter are added up by an adder to be direct-current converted. The amplitudes after the direct-current conversion are band-divided by third and fourth frequency selecting circuits, respectively, feedback amounts thereof are adjusted, and then fed back to the first and second operational amplifiers.

Transmission method and transmitter circuit

g(x) Storing means stores a correction function y=g(x) corresponding to the distortion of a high frequency power amplifier as a function of a voltage x provided to a power supply terminal of the high frequency power amplifier. Operating means receives the correction function g(x) and a complex vector modulation signal z provided from modulation signal generating means, then causes an inverse function gto operate on the absolute value and the phase of the complex vector modulation signal z having undergone polar coordinate conversion, and thereby outputs z'=g(z). This data is provided to the high frequency power amplifier. Further, triangular wave storing means is provided for storing a triangular wave having the same amplitude as that of the modulation signal. Either the triangular wave signal outputted from the triangular wave storing means or the modulation signal z&#x2032; is selectively provided to the high frequency power amplifier.

Transmitter and transceiver

In a transmitter of the present invention, a modulated signal is separated into an amplitude component and a phase component which are inputted to a radio-frequency modulated signal input terminal and a supply voltage terminal of a radio-frequency power amplifier. A voltage adjustment circuit is provided between an output terminal of the radio-frequency power amplifier and an amplitude amplification circuit having a feedback circuit. The voltage adjustment circuit changes the amount of isolation in accordance with the voltage level of the amplitude component. By this, the amplitude component of the radio-frequency modulated wave attenuates the level inputted to the feedback circuit of the amplitude amplification circuit through the supply voltage terminal of the radio-frequency power amplifier.

A phase shifting device includes a signal source; a variable phase shifter; first and second doubling circuits; and a 90-degree phase comparator. An output from the signal source is connected to an input of the variable phase shifter and to an input of the second doubling circuit, an output from the variable phase shifter is connected to an input of the first doubling circuit, an output from the first doubling circuit serves as a first output signal, and an output from the second doubling circuit serves as a second output signal. The first output signal and the second output signal are inputted to the 90-degree phase comparator. The amount of phase shift rotation of the variable phase shifter is changed by a phase shift control signal outputted from the 90-degree phase comparator. By this, an exact 90-degree phase shift is obtained.

Phase shifting device

A transmission circuit includes: a modulated signal generator; a modulated signal line where an OFDM modulated wave flows; a detector; a phase component line for transmitting a phase component; an amplitude component line for transmitting an amplitude component; a level judging circuit for judging the level of the amplitude component; a constant-voltage supply line; first and second selectors; a quadrature converter; and an RF power amplifier. An EER or pseudo-EER technique is performed in a region where the RF input-output characteristic of the RF power amplifier with an EER technique exhibits a linear response, whereas usual modulation is performed in a region where a nonlinear response is exhibited. The modulation method is switched using the level judging circuit and the selectors with reference to a threshold value which is the boundary between the region where the linear response is exhibited and the region where the nonlinear response is exhibited.

Transmission circuit

The present invention provides a transmitter conforming to the EER method in a wide frequency band at high efficiency. For this purpose, the amplitude component of a modulated signal is input to the power supply terminal of a high-frequency power amplifier, the I and Q quadrature signals thereof are input to the high-frequency input terminal of the high-frequency power amplifier, and the original modulated signal is obtained from the output of the high-frequency power amplifier. A collector voltage is supplied from DC&#x2014;DC converter grouphaving output voltages being different sequentially to an emitter followervia a switch group. One of the outputs of the DC&#x2014;DC converterstois selected depending on the level of the amplitude component as the collector voltage and supplied to the emitter follower, whereby the difference between the emitter voltage of he emitter followerand the collector voltage of the emitter followeris made smaller and the efficiency of the emitter followeris raised; furthermore, the power supply voltage of the high-frequency power amplifieris voltage-converted by the emitter follower, whereby operation in a wide frequency band is made possible.

An amplitude component and a phase component of a modulated signal are inputted into a power supply terminal and an input terminal of an RF power amplifier, respectively, and a modulated wave that is produced by demodulating an original modulated signal is obtained from the RF power amplifier. A supply voltage is supplied to an emitter follower and an operational amplifier via a switch group from a DC-DC converter group whose output voltages are sequentially different. As the supply voltage, any pair of outputs of DC-DC converters by the switch group is selected according to levels of the amplitude component, and provides them to the emitter follower and the operational amplifier. The emitter follower performs a DC conversion of the provided supply voltage to provide it to the RF power amplifier.

A transmission circuit includes: a modulated signal generator for outputting a modulated signal; an envelope detector for outputting an amplitude modulated voltage; an amplitude roll-off LPF for attenuating the amplitude modulated voltage by using a damping property represented by an exponential function in which an argument is exponentially proportional to a frequency; a power-supply-voltage generator for generating a power supply voltage in accordance with an amplitude value of the amplitude modulated voltage; a phase detector for outputting a phase modulated signal; a phase roll-off LPF for attenuating the phase modulated signal by using a damping property represented by an exponential function in which an argument is exponentially proportional to an offset frequency with respect to a center frequency; and an RF power amplifier.

Growing community of inventors

Osaka, Japan

Mitsuru Tanabe