Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Olympus Medical Systems Corporation

Eiji Okada

Hiroaki Ozeki

Takeshi Fujii

Akira Fujishima

Masatoshi Homan

Naoki Yuda

Yasuteru Asakawa

Masami Ueda

Motoi Furuta

A first wireless communication device includes first wireless communication circuitry that selectively operates in one of a plurality of bands and first control circuitry that sets a band in which the first wireless communication circuitry operates. The first control circuitry switches bands such that the first wireless communication circuitry operates in all of the plurality of bands within a certain cycle time. A second wireless communication device includes second wireless communication circuitry that selectively operates in one of the plurality of bands and second control circuitry that sets a band in which the second wireless communication circuitry operates. The second control circuitry switches to a different band when the second wireless communication device has been unable to communicate with the first wireless communication device.

Wireless communications system and wireless communication device

There is provided a power amplifier capable of readily reducing odd-order harmonic waves even in high frequencies. This power amplifier includes n current sources (where 'n' is a natural number equal to or greater than 3) that cause predetermined currents to flow; n switches that open and close current paths of the n current sources, respectively; and a signal generating section that generates n timing signals for turning on/off the n switches, respectively. In the power amplifier, the n timing signals are signals that have an identical duty ratio and that are different in phase; and the power amplifier outputs a signal amplified in power based on the currents flowing through the n current sources.

Power amplifier

A power amplifier is provided that generates timing signals which respectively turn on or off switches for respectively opening or closing current paths for current sources and which have same duty ratio and different phases and that adjusts current values for the current sources based on phase differences among the timing signals.

Harmonic rejection power amplifier

Filter circuit includes Nth-order active filters switching circuit which switches shorting or non-shorting of active filter, and power-supply control circuit which controls such that a power supply of active filter is turned off when switching circuit shorts active filter. A receiver employing filter circuit turns off the power supply of active filter not needed when no interference wave exists within a given range from a desired frequency band. The foregoing structure allows lowering the power consumption of filter circuit.

Filter circuit, and receiver and electronic device using the same filter circuit

An oscillator device includes a resonator including a coil and a capacitor connected to the coil in parallel; and an oscillator connected to the resonator. Electric waves are emitted from the coil to at least one receiving antenna of the receiver while the oscillator device changes position and direction over time. The coil has an outer diameter and a total length which is approximately the same as the outer diameter.

Oscillator device and transmitter module using same

Radio-frequency receiver contains a plurality of oscillation circuits that generates an oscillation frequency higher than that of digital broadcasting signals, selective switching circuit that selects two out of the oscillation circuits for signal output, and first and second frequency-divider sections that provide the signals with frequency dividing. The receiver receives two channels in the digital broadcasting signals at the same time by selection of oscillation signals and frequency dividing in the first and the second frequency-divider sections under the control of PLL controller.

Radio-frequency receiver and integrated circuit employed for the receiver

A receiver and an electronic device are provided that suppress deterioration of the signal waveform of a symbol. The receiver has a filter that sends out an output signal having a symbol at an arbitrary time interval; and an intermittent operation part that controls the filter intermittently at an arbitrary time interval, according to an output signal supplied from the filter. This arrangement prevents deterioration of the signal waveform of a symbol, by setting the timing for switching the signal for controlling the frequency characteristic of the filter, to an arbitrary period between symbol periods such as a guard interval.

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Osaka, Japan

Eiji Okada