Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Hisashi Adachi

Toru Matsuura

Hiroaki Kosugi

Toshifumi Nakatani

Shunsuke Hirano

Makoto Sakakura

Taiji Akizuki

Hiroyuki Asakura

Koji Takinami

Masanori Iida

Masakatsu Maeda

Tomoaki Maeda

Kaoru Ishida

Shigeru Morimoto

Masahiro Kumagawa

Yukio Hiraoka

Youichi Morinaga

Atsushi Ohara

Akinori Daimo

Yoshishige Yoshikawa

Atsushi Yamamoto

Kenichi Mori

Toshiaki Nakamura

Toshimitsu Matsuyoshi

Hiroshi Haruki

Tomoki Uwano

Takayuki Tsukizawa

Masaharu Udagawa

Toshio Obara

Yasunori Miyahara

Masahiko Sagisaka

Ryoichi Yamada

Hiroyuki Itokawa

Kazuo Nagao

Hiroyuki Nakamura

Toshio Ishizaki

Tsuguhiro Korenaga

Hiroyuki Yoshikawa

Hiroyuki Handa

Seiji Fujiwara

Yuji Saito

Mikihiro Shimada

Masayuki Miyaji

Yoshio Horiike

Takeshi Miura

Kazuhiko Ikeda

Hisashi Takahashi

Shinichiro Uemura

Hidenobu Kato

Takayuki Matsumoto

Hiroki Kojima

Ikuo Ohta

Jyunichi Yoshizumi

Kayo Nakanishi

Junichi Yasuno

Daisuke Tobise

Tokio Endoh

Shinichi Kugou

Masanori Ilda

Hiroyuki Shirufido Sanadayama 7A Asakura

A power amplification apparatus generates a code for controlling the number of class D power amplifiers that are in operation among a plurality of class D power amplifiers, changes the duty ratio of a carrier wave signal in accordance with output voltage, and amplifies a transmission signal. A code for decreasing the number of class D power amplifiers in operation is generated when the duty ratio of the carrier wave signal is increased, while a code for increasing the number of class D power amplifiers in operation is generated when the duty ratio of the carrier wave signal is decreased.

Power amplification apparatus and control method

A power amplification device includes: a first power-amplifier array including a plurality of first switching elements that constitute a class-D power amplifier for a higher bits; a second power-amplifier array including a plurality of second switching elements that constitute a class-D power amplifier for a lower bits; and a capacitor array including a plurality of capacitance elements. The second switching elements have a larger on-resistance than the first switching elements. The first power-amplifier array is arranged between the second power-amplifier array and the capacitor array.

Power amplification device and transmitter

A transmitting apparatus and transmission method are capable of easily and correctly mixing an in-phase component and a quadrature-phase component in a quadrature modulator. A local signal with a duty ratio of 25% or smaller is generated without using frequency which is a multiple of frequency of the local signal. Without providing switches in series to the outputs of I and Q amplifiers, a duty ratio of 25% or less is obtained. for the local signal, and class-D unit amplifiers are operated such that one of the I amplifier and the Q amplifier is connected to the output side in any state regardless of whether an output power control signal is at an on-level or an off-level. In producing the 25% duty ratio, a local signal with a 50% duty ratio is converted so as to have a duty ratio of 25% by I and Q duty converters.

Transmitting apparatus and transmission method

A transmission apparatus includes a digital amplifier having a plurality of class-D amplifiers connected in parallel to each other, each of the class-D amplifiers including a logic circuit that processes input signals from two input terminals and outputs the input signals to one of two output terminals, according to a selection signal, and including capacitors connected in series to the two output terminals, respectively, a first selection circuit that outputs either an in-phase component or a quadrature component of a transmission signal to the digital amplifier depending on the selection signal, and a second selection circuit that outputs either an in-phase component carrier signal or a quadrature component carrier signal to the digital amplifier depending on the selection signal.

Transmission apparatus and transmission method

A frequency synthesizer includes a digitally-controlled oscillator and an oscillation frequency control unit. The digitally-controlled oscillator includes a loop-shaped transmission line path having an odd number of parallel portions in each of which two conductors are arranged in parallel to each other with a space therebetween, and an odd number of intersection portions in each of which two conductors intersect spatially, an active circuit coupled between the two conductors, and a first variable capacitance unit and a second variable capacitance unit. The oscillation frequency control unit includes a &#x3a3;&#x394; modulation circuit for subjecting to &#x3a3;&#x394; modulation a first control signal for switching a high capacitance state and a low capacitance state of a first variable capacitance element included in the first variable capacitance unit.

Digitally-controlled oscillator, frequency synthesizer and radio communication device

A data converter that converts an input signal to a signal to be inputted to an amplifier. Specifically, the data converter includes: an amplitude detection section that detects an amplitude level of the input signal; a region determination section that determines whether or not an input power to the amplifier is in a non-linear region of the amplifier based on the amplitude level of the input signal detected by the amplitude detection section; and a signal processing section that converts the input signal to a signal having a lower resolution than that of the input signal if the region determination section determines that the input power to the amplifier is in the non-linear region of the amplifier.

Data converter and data conversion method, and transmitter circuit, communications device and electronic device using the same

A transmission circuit capable of transmitting a modulated wave signal using polar modulation in a broad band and with low power consumption is provided. The transmission circuit generates an amplitude signal and a phase signal based on data to be transmitted, and separates the amplitude signal into a low-frequency amplitude signal and a high-frequency amplitude signal. The transmission circuit amplitude-modulates the phase signal in a broad band using the high-frequency amplitude signal in a high-frequency voltage control sectionand an amplitude modulation sectionand amplitude-modulates the phase signal into low power consumption using the low-frequency amplitude signal in a low-frequency voltage control sectionand amplitude modulation section

Transmission circuit

A voltage controlled oscillator, a variable frequency divider, a phase comparator, and a loop filterform a Phase Locked Loop (PLL). A sigma-delta modulatorsigma-delta modulates data obtained by adding a fractional part Mof the frequency division factor data with modulation data X by using an output signal of the variable frequency divideras a clock. An output signal of the sigma-delta modulatoris added to an integral part Mof the frequency division factor data, and the resultant data becomes effective frequency division factor dataof the variable frequency divider. An output signal of the sigma-delta modulatoralso becomes control dataafter passing through a D/A converter, a low-pass filter, and an amplitude adjustment circuit. The control datais inputted into a frequency modulation terminal of the voltage controlled oscillator. Therefore, it is possible to provide a frequency modulator that can use a reference signal source having no frequency modulation function, and perform modulation over a wide range of frequencies based on a digital modulation signal.

Frequency modulator, frequency modulating method, and wireless circuit

A clock signal generation apparatus containing variable delay devices for varying the delay time of two-phase clock signals used in a load circuit that uses non-overlap clock signals; a non-overlap detector for detecting a non-overlap time in the H-level zones of the two-phase clock signals and outputting a detection signal corresponding to the non-overlap time; and a control signal generation section for generating a control signal that is used to control the variable delay devices on the basis of the detection signal from the non-overlap detector, and capable of securely generating the two-phase clock signals having an optimal non-overlap time while absorbing fluctuations due to temperature characteristics, power supply voltage characteristics and individual differences in components.

Clock signal generation apparatus

A multibit quantizer is provided, at its input terminals, with a variable gain circuit and an offset addition circuit to perform tracking control in which for each sampling time, the level of an offset signal of the offset addition circuit is adjusted based on output digital data of an output processing circuit and the preceding control signal of an offset control circuit so that the quantizer operates without causing a saturation operation. As a result, the output digital data, in which the number of bits is greater than the number of bits of the quantizer by the offset value controlled by the offset addition circuit, is outputted from the output processing circuit for each sampling time.

Delta sigma A/D modulator

The present invention aims to provide a transmitter circuit that is capable of suppressing quantization noise and operating with a high efficiency, a data converter sectionand a data conversion method for use therein, and a communications device using the same. The data converter sectionof the present invention performs a predetermined data conversion operation on an input signal. The data converter sectionincludes: a signal processing sectionfor discretizing the input signal to produce a signal having a lower resolution magnitude-wise than that of the input signal; a subtractor sectionfor subtracting the input signal from the signal having a lower resolution to extract quantization noise; a filterfor extracting quantization noise near an intended wave frequency; and a subtractor sectionfor removing the quantization noise near the intended wave frequency from the signal having a lower resolution.

Data converter device and data conversion method, and transmitter circuit, communications device and electronic device using the same

The present invention is intended to attain simplified circuit configuration and low current consumption in a discrete time amplifier circuit and an AD converter, to improve the convergence from the transient response state to the steady state of the amplifier circuit and to reduce noise and distortion owing to the variation in the output common-mode voltage. The discrete time amplifier circuit and the AD converter are provided with a switched-capacitor common-mode feedback (CMFB) circuit capable of detecting and feeding back the output common-mode voltage at every sampling timing in the case that the circuit operates at double sampling timing (every &#xbd; cycle).

Discrete time amplifier circuit and analong-digital converter

Radio communication apparatus comprising an antenna, a transmitting circuit of outputting a transmitting signal in a first frequency band. A duplexer connected to the antenna and having a single-phase input terminal and a balanced output terminal, conveying the transmitting signal inputted to the single-phase input terminal to the antenna. The duplexer outputs a receiving signal in a second frequency band different from the first frequency band received from the antenna substantially as a differential signal from the balanced output terminal. A receiving circuit connected to the balanced output terminal and having a circuit in which a gain of a signal of a differential component is higher than that of a signal of an in-phase component, or a loss of the signal of the differential component is lower than that of the signal of the in-phase component.

Radio communication apparatus, radio communication method, antenna apparatus and first duplexer

The amplitude modulator comprises: an angle modulator for angle-modulating a phase signal to be inputted; a waveform shaping means in which, (1) when the magnitude of an amplitude signal to be inputted becomes smaller than a first prescribed value, a waveform of the amplitude signal is shaped so that the magnitude of the amplitude signal of the portion which becomes small becomes the first prescribed value; and/or (2) the waveform shaping means in which, when the magnitude of the amplitude signal to be inputted becomes larger than the second prescribed value which is larger than the first prescribed value, the waveform of the amplitude signal is shaped so that the magnitude of the amplitude signal of the portion which becomes larger becomes the second prescribed value; and an amplitude modulator for amplitude modulating the signal of the output of the angle modulator by the signal of the output of the waveform shaping means.

Modulation circuit device, modulation method and radio communication device

The digital controlled oscillator includes a variable capacitance section having a first capacitor array of a plurality of first variable capacitors and a second capacitor array of a plurality of second variable capacitors, and generates a signal having an oscillation frequency corresponding to the capacitance value of the variable capacitance section. The first capacitance change amount in the individual first variable capacitors is a value obtained by multiplying the second capacitance change amount in the individual second variable capacitors by an integer equal to or more than 2, and the number of second variable capacitors is equal to or more than a value obtained by subtracting 1 from the integer equal to or more than 2.

Digital controlled oscillator, frequency synthesizer, radio communication apparatus using the same, and control method for the same

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Osaka, Japan

Hisashi Adachi