研究者詳細 - 山田　寛喜

論文 - 山田　寛喜

分割表示 893 件中 81 - 100 件目／全件表示 >>

ALOS-PALSAR Quad-Polarization Images Over Singapore 招待査読

Yoshio Yamaguchi, Ryoichi Sato, Hiroyoshi Yamada

2015 IEEE 5TH ASIA-PACIFIC CONFERENCE ON SYNTHETIC APERTURE RADAR (APSAR) 210 - 213 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：IEEE

This paper presents the scattering power decomposition images over Singapore using 3 fully polarimetric SAR data acquired with ALOS-PALSAR. The land cover are precisely imaged with RGB color-coding indicating R: the double bounce scattering, G: the volume scattering, and B: the surface scattering. It is seen the image is useful for identifying various objects including urban area, forest, agricultural area, in addition to numerous ships around Singapore sea area.

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Fundamental Study on Multi-baseline SAR Tomography Using Airborne X-band SAR 査読

Tomoki Kato, Hiroyoshi Yamada, Yoshio Yamaguchi, Ryoichi Sato, Shoichiro Kojima, Motofumi Arii

2015 IEEE 5TH ASIA-PACIFIC CONFERENCE ON SYNTHETIC APERTURE RADAR (APSAR) 15 - 19 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：IEEE

Recently, microwave remote sensing has been used for observation of the global environment extensively. There are many techniques in the microwave remote sensing. Among them, SAR (Synthetic Aperture Radar) Tomography is one of the emerging technique that can realize three dimensional imaging, by using multiple flight paths. The data pixels in each SAR image obtained at the slightly different paths may be regarded as the observed data with an array antenna. Thus, it is applying the Direction of Arrival (DOA) estimation technique to the array data, we estimate angle of dominant scatterers, or height of the targets.
In this report, we provide preliminary results of the multi-baseline SAR Tomography observed by the PiSAR2-X, airborne X-band SAR of NICT, Japan.

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仮想アレーを用いた角度分解能向上による二次元表層流速推定結果について

龍川卓也, 山田寛喜, 山口芳雄, 平野圭蔵, 伊藤浩之

九州大学応用力学研究所研究集会「海洋レーダを用いた海況監視システムの開発と応用」 2014年12月

キャリブレーション誤差を考慮したMassive MIMOの伝送効率評価

西森健太郎, 平栗健史, 山田寛喜

電子情報通信学会技術研究報告 AP2014-129 7 - 12 2014年11月

大きく傾いた建築物群の検出を目的とした偏波散乱解析

五十嵐裕平, 佐藤亮一, 真坂元貴, 山口芳雄, 山田寛喜

第43回電磁界理論シンポジウム EMT-14-170 2014年11月

四成分散乱モデル分解法に基づくスペックルフィルタリングの検討

落合拓也, 山口芳雄, 山田寛喜, 崔一

2014年度電子情報通信学会信越支部大会 ( 4A-2 ) 49 - 49 2014年10月

KR変換を用いた広帯域DOA推定の分解能特性に関する検討

石山優, 山田寛喜, 山口芳雄

2014年度電子情報通信学会信越支部大会 ( 4A-4 ) 51 - 51 2014年10月

指向性アンテナを用いたMIMOセンサによる室内外検出特性

平石壮, 西森健太郎, 田代翼, 本間尚樹, 山田寛喜

2014年度電子情報通信学会信越支部大会 ( 4B-2 ) 53 - 53 2014年10月

四成分散乱モデル分解による積雪についての検討

高橋祐太, 山口芳雄, 山田寛喜

2014年度電子情報通信学会信越支部大会 ( 4B-3 ) 54 - 54 2014年10月

屋内における人物の行動追跡に関する実験的検討

佐藤耕平, 山田寛喜, 山口芳雄

2014年度電子情報通信学会信越支部大会 ( 4B-4 ) 55 - 55 2014年10月

MIMOドップラレーダにおけるMUSIC法を用いた屋内人物位置推定

若松洋介, 山田寛喜, 山口芳雄

2014年度電子情報通信学会信越支部大会 ( 4D-3 ) 62 - 62 2014年10月

レンジ・ドップラレーダを用いた人物の動作検出，抽出に関する実験的検討

福島真也, 山田寛喜, 小林弘一, 山口芳雄

2014年度電子情報通信学会信越支部大会 ( 4D-4 ) 63 - 63 2014年10月

Soil Moisture Effects on Polarimetric Radar Backscatter from Forest in Various Incidence Angles

Takuma Watanabe, Hiroyoshi Yamada, Motofumi Arii, Ryoichi Sato, Yoshio Yamaguchi

2014年度電子情報通信学会信越支部大会 ( 6A-3 ) 192 - 192 2014年10月

海洋レーダによる表層流速推定へのKhatri-Rao積仮想アレー適用について

龍川卓也, 山田寛喜, 山口芳雄, 平野圭蔵, 伊藤浩之

2014年度電子情報通信学会信越支部大会 ( 4A-3 ) 50 - 50 2014年10月

Study on Moisture Effects on Polarimetric Radar Backscatter from Forested Terrain 査読

Takuma Watanabe, Hiroyoshi Yamada, Motofumi Arii, Ryoichi Sato, Sang-Eun Park, Yoshio Yamaguchi

IEICE TRANSACTIONS ON COMMUNICATIONS E97B ( 10 ) 2074 - 2082 2014年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG

Soil moisture retrieval from polarimetric synthetic aperture radar (SAR) imagery over forested terrain is quite a challenging problem, because the radar backscatter is affected by not only the moisture content, but also by large vegetation structures such as the trunks and branches. Although a large number of algorithms which exploit radar backscatter to infer soil moisture have been developed, most of them are limited to the case of bare soil or little vegetation cover that an incident wave can easily reach the soil surface without serious disturbance. However, natural land surfaces are rarely free from vegetation, and the disturbance in radar backscatter must be properly compensated to achieve accurate soil moisture measurement in a diversity of terrain surfaces. In this paper, a simple polarimetric parameter, co-polarized backscattering ratio, is shown to be a criterion to infer moisture content of forested terrain, from both a theoretical forest scattering simulation and an appropriate experimental validation under well-controlled condition. Though modeling of forested terrain requires a number of scattering mechanisms to be taken into account, it is essential to isolate them one by one to better understand how soil moisture affects a specific and principal scattering component. For this purpose, we consider a simplified microwave scattering model for forested terrain, which consists of a cloud of dielectric cylinders as a representative of trunks, vertically stood on a flat dielectric soil surface. This simplified model can be considered a simple boreal forest model, and it is revealed that the co-polarization ratio in the ground-trunk double-bounce backscattering can be an useful index to monitor the relative variation in the moisture content of the boreal forest.

DOI： 10.1587/transcom.E97.B.2074

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DOA Estimation for Multi-Band Signal Sources Using Compressed Sensing Techniques with Khatri-Rao Processing 査読

Terada, Tsubasa, Nishimura, Toshihiko, Ogawa, Yasutaka, Ohgane, Takeo, Yamada, Hiroyoshi

IEICE TRANSACTIONS ON COMMUNICATIONS E97B ( 10 ) 2110 - 2117 2014年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG

Much attention has recently been paid to direction of arrival (DOA) estimation using compressed sensing (CS) techniques, which are sparse signal reconstruction methods. In our previous study, we developed a method for estimating the DOAs of multi-band signals that uses CS processing and that is based on the assumption that incident signals have the same complex amplitudes in all the bands. That method has a higher probability of correct estimation than a single-band DOA estimation method using CS. In this paper, we propose novel DOA estimation methods for multi-band signals with frequency characteristics using the Khatri-Rao product. First, we formulate a method that can estimate DOAs of multiband signals whose phases alone have frequency dependence. Second, we extend the scheme in such a way that we can estimate DOAs of multi-band signals whose amplitudes and phases both depend on frequency. Finally, we evaluate the performance of the proposed methods through computer simulations and reveal the improvement in estimation performance.

DOI： 10.1587/transcom.E97.B.2110

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インプリシットビームフォーミングのための装置内位相誤差によるチャネル容量特性評価

佐々木叡, 西森健太郎, 山田寛喜

電子情報通信学会総合大会 ( B-1-186 ) 2014年9月