Fujitsu Corporation

Shohei Ishikawa

Kazuo Nagatani

Hiroyoshi Ishikawa

Hajime Hamada

Nobukazu Fudaba

Yuichi Utsunomiya

Takashi Yamagajo

Teruhisa Ninomiya

An antenna device includes: a ground plate; a first patch, provided on one surface side of the ground plate and including two first power feeding portions provided in a region surrounded by a first contour at positions spaced away from a first position with a first distance, configured to resonate with a first frequency; a second patch, provided between the ground plate and the first patch and including two second power feeding portions provided in a region surrounded by a second contour at positions spaced away from a second position with a second distance and a slit formed in the region, configured to resonate with a second frequency lower than the first frequency; and an inter-patch connection portion configured to electrically couple the first position of the first patch and the second position of the second patch.

Antenna device and antenna system

An antenna device, includes: a ground plate to which first and second antennas, each including a radiating element and a ground terminal, are connected, with one of the first and second antennas being powered, the ground plate including: a first slit extending from a portion where the ground terminal of one antenna of the first and second antennas is connected to the ground plate, in a direction along to the ground terminal, and a second slit extending from the tip of the first slit in a direction along to the radiating element.

Antenna device, electronic apparatus, and wireless communication method

According to an embodiment, an antenna apparatus include a ground plate; a first element disposed along the ground plate; a second element disposed along the first element at an opposing side of the ground plate; a connecting part to connect first and second terminal parts of the first element with first and second terminal parts of the second element, respectively, or to connect the first and second terminal parts of the first element with the ground plate; a first power feeding portion to feed power at a midpoint of the first or second element in a longitudinal direction when the first and second elements are connected together by the connecting part; and a second power feeding portion to feed power to the first element or the ground plate when the first element and the ground plate are connected together by the connecting part.

Antenna apparatus

A distortion compensation apparatus includes a distortion compensation signal generation unit that performs, on a transmission signal, distortion compensation processing using a series operation; a coefficient updating unit that updates series operation coefficients used for the series operation based on a feedback signal of a power amplification output which is output through power amplification processing of a distortion compensation signal output from the distortion compensation signal generation unit, and based on the distortion compensation signal; a memory that stores the distortion compensation signal corresponding to a transmission signal having a given power value and the feedback signal of the power amplification output as restraint information; and a control unit that performs control so that, in accordance with the power value of the transmission signal, restraint information corresponding to a power value different from the power value of the transmission signal is read and used for updating the series operation coefficients.

Distortion compensation apparatus and method

A predistortion apparatus for compensating for a distortion arising from a non linear property in input to output characteristics of an amplifier, by processing calculation of a plurality of coefficients for a plurality of power series defining the predistortion characteristics for a plurality of power ranges, respectively, the predistortion apparatus includes: a coefficient update unit for setting and updating coefficients of the power series to provide the predistortion characteristics for the plurality of power ranges in accordance with a comparison between the input and output of the amplifier; and a determination unit for determining at least one threshold value defining the plurality of power ranges by shifting the threshold value and operating the coefficient update unit for updating the coefficients for each of the power series corresponding to each of the power ranges defined by the shifted threshold value.

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Yokohama, Japan

Shohei Ishikawa