Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Daikin Industries, Ltd.

Panasonic Intellectual Property Corporation of America

Nkk Corporation

Shigeru Morimoto

Masahiro Maeda

Toru Matsuura

Hisashi Adachi

Yorito Ota

Kaoru Ishida

Yoshihiro Hara

Maki Nakamura

Masaru Yamaoka

Hidetoshi Ishida

Shunsuke Hirano

Michihiro Matsumoto

Yasuo Yoshimura

Kazunori Kurimoto

Hiroyuki Masato

Naofumi Nakatani

Kazuhiro Kuroyama

Ryo Kitamura

Koji Ishihara

Junko Iwanaga

Yukihiro Omoto

Eiichi Sadayuki

Mahbub Rashid

Morio Nakamura

Kazuhiro Asai

Motonari Katsuno

Hiroshi Omori

A wireless communication apparatus includes: a first antenna; a second antenna; a variable phase shifting unit that changes a phase of a high frequency signal to be received or transmitted via the first antenna and the second antenna; and a phase-information table storage unit that stores a phase information table in which phase information is associated with each of a plurality of communication terminals as communication partners. When communicating with one communication terminal out of the plurality of communication terminals via the first antenna and the second antenna, the variable phase shifting unit changes a phase of a high frequency signal on the basis of phase information stored in the phase information table in association with the one communication terminal.

Wireless communication apparatus and method for controlling wireless communication apparatus

An RFID tag includes an antenna coil configured to transmit and receive a signal through near field communication, a signal processing circuit configured to process the signal transmitted and received by the antenna coil, a capacitive element arranged in series between the antenna coil and the signal processing circuit, and a control unit configured to control the capacity value of the capacitive element. The control unit changes the capacity value of the capacitive element according to whether a voltage is applied from an external power supply.

Communication apparatus

A radio frequency identification (RFID) device includes: a contact interface for wired communication with a host; a contactless interface for contactless communication with a reader/writer; a command processing unit that obtains a command from the reader/writer in the contactless communication and process the command, the command instructing a data access; and a memory that holds data. The command processing unit determines a communication mode, and (i) executes the data access instructed in the command between the reader/writer and the memory, when the communication mode is determined as a first communication mode, and (ii) executes the data access instructed in the command between the reader/writer and the host, when the communication mode is determined as a second communication mode.

RFID device, host, RFID-embedded apparatus, and method of controlling RFID device

A polar modulator of the present invention includes: a first function block which generates an amplitude signal and a phase signal; a second function block which adjusts the signal delay between the amplitude signal and the phase signal; a third function block which allows the low frequency component of the amplitude signal to pass therethrough; a fourth function block which modulates the phase of the phase signal; a fifth function block which outputs a modulation voltage, based on the amplitude signal; a sixth function block which modulates the amplitude of the phase signal, based on the modulation voltage; a seventh function block which measures the temperature of at least one function block; and an eighth function block which calculates a compensation amount for the signal delay, based on the measured temperature. The second function block adjusts the signal delay, based on the compensation amount.

Polar modulator

A transmission circuit adjust a difference between signal delay amounts in an amplitude path and a phase path with a low power consumption. An amplitude modulation section amplitude-modulates a phase modulation signal outputted from a phase modulation section with a voltage control signal provided by a regulator to generate a transmission signal for an output of an antenna. Similarly, a feedback signal generation section amplitude-modulates the phase modulation signal with a voltage control signal to generate a feedback signal. The signal is fed back to a delay adjustments sections used for calculating and adjusting the difference between the signal delay amounts in the amplitude path and the phase path. The feedback signal generation section is attained by a power amplifier having the same configuration as the amplitude modulation section and a smaller circuit scale.

Transmission circuit and communication apparatus using polar modulation method

A signal generating sectionoutputs an amplitude signal and a frequency signal by conducting a signal processing on inputted data. A regulatoroutputs a signal that is proportional to a magnitude of the amplitude signal. The signal outputted from the regulatorpasses through a low pass filter, and is inputted into a power amplifier. The power amplifierconducts an amplitude modulation on a frequency signal on which an angle modulation is conducted by an angle modulation section, using a signal outputted from the low pass filter. A controlling sectioncontrols an amount of attenuation of a radio frequency component at the low pass filterbased on information such as: a modulation method of the inputted data; a modulation condition of the inputted data; a reception band; an output power of a modulation signal; and a frequency of the modulation signal.

Transmitter and communication apparatus using the same

Provided is a transmission circuit capable of operating with high linearity and with low noise. An AM variable fc filter uses an AM cutoff frequency to remove a high frequency component from an amplitude signal. An amplifier supplies a power amplifier with a voltage which is a result of amplifying the amplitude signal outputted from the AM variable fc filter. A PM variable fc filter uses a PM cutoff frequency to remove a high frequency component from a phase signal. A phase modulator phase-modulates the phase signal outputted from the PM variable fc filter to output a high-frequency phase-modulated signal. The power amplifier amplifies the high-frequency phase-modulated signal by using the voltage supplied from the amplifier, and outputs a resultant signal as a transmission signal. The AM variable fc filter and the PM variable fc filter respectively control the AM cutoff frequency and the PM cutoff frequency such that the AM cutoff frequency and the PM cutoff frequency each have an opposite characteristic to that of an output power of the transmission signal.

Transmission circuit and communication device

A polar modulation transmission apparatus is disclosed, which reduces the circuit scale by removing isolators and which reduces the heat loss of a power amplifier. In this apparatus, current detecting sectiondetects current value Icc of current flowing from power supply voltage sectionto power amplifier, and power control sectionoutputs control signal Sto power apply sectionbased on power control signal Sto be inputted and current value Icc. Power apply sectionforms amplitude modulation signal Sby multiplying baseband amplitude modulation signal Sby control signal S, and regulatorsupplies to power amplifierpower supply voltage Sconverted into power supply voltage Sby amplitude modulation signal S. Power amplifierobtains RF transmission signal Sby amplifying the power of phase modulation high-frequency signal Sas the power supply of power supply voltage S

Polar modulation transmission apparatus

Provided is a transmission circuit which is capable of compensating for an offset voltage and a sensitivity characteristic of a PA, and operating with low distortion and high efficiency. A regulatorsupplies, to a PA, a voltage which is controlled in accordance with an amplitude signal to which a first offset value has been added. A regulatorsupplies, to a PA, a voltage which is controlled in accordance with an amplitude signal to which a second offset value has been added. The PAamplifies, in accordance with the voltage supplied from the regulator, a phase-modulated signal outputted from a phase modulator. The PAamplifies, in accordance with the voltage supplied from the regulator, an output signal of the PA. A digital blockcontrols the first and second offset values in accordance with temperature information T measured by a temperature measuring section

Transmission circuit comprising multistage amplifier, and communication device

A modulatorcorrects an amplitude signal Rd by adding thereto an offset value &#x3b1; and generates, based on the corrected amplitude signal Rd, an amplitude signal Ra for amplitude-modulating a radio-frequency signal. The modulatorincludes: an offset voltage measurement sectionoperable to measure an offset voltage Vof the amplitude signal Ra; a correction value calculation sectionoperable to obtain a difference value &#x394;Vbetween the offset voltage Vmeasured by the offset voltage measurement sectionand an initial value of the offset voltage Vand operable to calculate, based on the difference value &#x394;V, a correction value Vfor correcting the offset voltage V; and an addition sectionoperable to add the correction value Vcalculated by the correction value calculation sectionto a signal processed until the amplitude signal Ra is generated from the amplitude signal Rd.

Transmitter and communication apparatus

Provided is a transmitter circuit capable of operating with low distortion and high efficiency even in a modulation method using wide modulation bandwidth. In the transmitter circuit, a signal generation section () generates an amplitude signal and an angle-modulated signal. Based on a predetermined characteristic, a compensating filter () wave-shaping-processes the amplitude signal. A regulator () outputs a signal in accordance with a magnitude of the signal which has been wave-shaping-processed by the compensating filter (). An amplitude modulator section () amplitude-modulates the angle-modulated signal by using the signal outputted from the regulator (). A characteristic of the compensating filter () is an inverse of a transfer characteristic between an input at the regulator () and an output at the amplitude modulator section ().

Polar modulation transmitter circuit and communications device

A phase modulation section () generates a first modulated signal including phase information. An amplitude signal control section () generates a second modulated signal including amplitude information. A waveform shaping section (), when an amplitude of the second modulated signal is larger than a regulated value generates a waveform-shaped modulated signal. An amplitude modulated voltage supply section () amplifies the waveform-shaped modulated signal based on the supply voltage from a voltage control section () and supplies the amplified signal to a power amplification section (). The power amplification section () amplifies the first modulated signal based on the amplitude modulated voltage, and outputs the resultant signal. The waveform shaping section () adjusts the regulated value in accordance with a factor for changing a distorted power generated by the power amplification section (), such that an ACP generated by the power amplification section () becomes a first predetermined value or smaller.

Polar modulator and wireless communication apparatus using the same

A transmission circuit is provided which can output a stable transmission signal independently of the temperature characteristics of an amplitude modulating section. A signal generating section generates an amplitude signal and a phase signal. A regulator supplies a voltage which is controlled, depending on the amplitude signal, to the amplitude modulating section. An angle modulating section subjects the phase signal to angle modulation to output an angle-modulated signal. A temperature detecting section outputs temperature information of the amplitude modulating section. A gain control section controls a gain of a variable gain amplifier based on the temperature information of the amplitude modulating section. The variable gain amplifier amplifies the angle-modulated signal using the gain controlled by the gain control section. The amplitude modulating section subjects the angle-modulated signal to amplitude modulation using a voltage which is controlled, depending on the amplitude signal, to output an amplitude-modulated signal.

Transmission circuit and communication apparatus employing the same

An amplifier includes a modulation coder receiving an original modulation signal and generating an amplitude signal and a phase signal, a voltage adjusting instrument which generates an amplitude modulation signal from the amplitude signal, a carrier generator generating a phase modulation signal from the phase signal, and an amplification device receiving the phase modulation signal and the amplitude modulation signal serving as a bias voltage and outputting a modulation signal obtained by restoring and amplifying the original modulation signal. The voltage adjusting instrument determines a DC offset voltage on the basis of a level control signal indicating the level of the amplitude modulation signal and generates the amplitude modulation signal to which the DC offset voltage is added.

Amplifier, information communication apparatus and amplification method

The present invention provides an amplifier for amplifying a high-frequency signal and outputting an amplified signal. The amplifier includes: an amplification element which is a bipolar transistor or a field-effect transistor; and an inductor connected between a base and a collector or between a gate and a drain of the amplification element. The inductance of the inductor is chosen so that, within a predetermined frequency range, a parallel resonance occurs with a parasitic capacitor of the amplification element and an intrinsic capacitor of the amplification element, the intrinsic capacitor being a base-collector capacitance or a gate-drain capacitance.

Growing community of inventors

Osaka, Japan

Shigeru Morimoto