Other

Hitachi, Ltd.

Tatsuto Okamoto

Satoshi Tanaka

Toshiro Suzuki

Takashi Inoue

Satoshi Masuda

Masao Yamane

Sumaru Niida

Tsuyoshi Taniguchi

Taro Kitayama

Disclosed is a control apparatus capable of more effectively utilizing radio resources. Mobile stations positioned close to each other are treated as one group, and a direction and width (radiation angle) of a beam radiated from an adaptive array antenna is controlled for each group so that one beam capture one group. To be concrete, a plurality of mobile stations are classified into groups by a classification section , and an area to which each group moves is estimated by a directivity determination section . The adaptive array antenna is controlled by the directivity control section so that one beam can cover an area in which one group is positioned and the area to which this one group moves.

Method of controlling directional antenna and apparatus of the same

This invention is intended to realize a high frequency switch with a low distortion characteristic. In an SPDT switch consisting of a plurality of FETs, the FET on the receiver side through which a received signal passes and the shunt FET on the transmitter side are each formed of series-connected FETs, and a capacitor is connected between the first gate and the source and between the second gate and the drain. An inductance is connected in parallel with a series connection of FETs. This easily realizes a high frequency switch having a low voltage and a low distortion characteristic. The 1 dB compression level, an index of input-output characteristic, can be improved more than 5 dB over the conventional SPDT switch at an input level.

Low distortion switch

Growing community of inventors

Yokohama, Japan

Tatsuto Okamoto