Mitsubishi Denki Kabushiki Kaisha

Junichi Nagano

Yukio Ikeda

Masatoshi Nakayama

Yuji Sakai

Kenichi Horiguchi

Haruyasu Senda

A relay station is composed of a main reception antennafor receiving both a radio wave of a parent station and a go-around radio wave of a relay station, a subsidiary reception antennafor receiving the go-around radio wave of the relay station, a changeable attenuatorand a phase shifting unitfor changing an amplitude and phase of a signal received in the subsidiary reception antenna, a composite signal producing unitfor producing a composite signal from a signal received in the main reception antennaand the signal sent from the phase shifting unit, an electric power detecting unitfor obtaining a composite electric power from a composite voltage extracted in a directivity coupling unit, and a microcomputerfor controlling a change of amplitude in the changeable attenuatorand a change of phase in the phase shifting unitso as to minimize an average value of the composite electric power obtained in the electric power detecting unit

Repeater

A feedforward amplifier combines an input signal delayed by a delay circuit with an output signal by a combiner; down-converts the output of the combiner to a low frequency by a frequency converter; extracts a distortion component from the output of the frequency converter; measures the distortion component by a power detector; and controls a second vector regulator of a distortion canceling loop by a controller such that the distortion component measured becomes minimum.

Growing community of inventors

Tokyo, Japan

Junichi Nagano