研究者詳細 - 山田　寛喜

論文 - 山田　寛喜

分割表示 893 件中 381 - 400 件目／全件表示 >>

DOA推定のためのアレー校正手法 −信号処理的アプローチ−

山田寛喜

電子情報通信学会総合大会 ( B-1-13 ) 2008年3月

Beamspace Post-Doppler法を用いたMWFの性能評価

岩倉慶成, 鈴木潤一郎, 山田寛喜, 山口芳雄, 田邊正宏

電子情報通信学会総合大会 ( B-1-216 ) 2008年3月

偏波相関係数を用いた人工物検出に関する一考察

浅川雄祐, 佐藤亮一, 山口芳雄, 山田寛喜

電子情報通信学会総合大会 ( B-1-218 ) 2008年3月

Two-dimensional target location estimation technique using leaky coaxial cables 査読

Kenji Inomata, Takashi Hirai, Yoshio Yamaguchi, Hiroyoshi Yamada

IEICE TRANSACTIONS ON COMMUNICATIONS E91B ( 3 ) 878 - 886 2008年3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

This paper presents a target location estimation method that can use a pair of leaky coaxial cables to determine the 2D coordinates of the target. Since convention location techniques using leaky coaxial cables can find a target location along the cable in I D, they have been unable to locate it in 21) planes. The proposed method enables us to estimate target on a 21) plane using, 1) a beam-forming technique and 2) a reconstruction technique based on Hough transform. Leaky coaxial cables are equipped with numerous slots at regular interval, which can be utilized as antenna arrays that acts both as transmitters and receivers. By completely exploiting this specific characteristic of leaky coaxial cables, we carried out an antenna array analysis that performs in a beam-forming fashion. Simulation and experimental results support the effectiveness of the proposed target location method.

DOI： 10.1093/ietcom/e91-b.3.878

Web of Science

researchmap

仮想アレーを用いたリニアアレーDOA推定の仰角依存性の校正について

内藤孝, 山田寛喜, 山口芳雄

電子情報通信学会技術研究報告 AP2007-130 ( 1 ) 45 - 50 2008年1月

Ku-band FM-CW POLSARによるCCD基礎検討

中村純, 青山和康, 山口芳雄, 山田寛喜, 降旗正忠, 熊谷信夫

電子情報通信学会技術研究報告 SANE2007-118 ( 1 ) 2008年1月

高速な散乱行列取得による移動ターゲットの四成分電力分解

青山和康, 中村純, 山口芳雄, 山田寛喜

電子情報通信学会技術研究報告 SANE2007-123 ( 1 ) 123 - 127 2008年1月

記述言語：日本語出版者・発行元：一般社団法人電子情報通信学会

散乱行列を高速に取得することができる遅延線型偏波レーダーシステムを開発した.通常,偏波レーダーは信号を送信する際,H,V偏波をスイッチによって切り替え,2つの偏波信号を送信する.この2つの偏波の切り替えに時間を要するため,送信したH偏波を受信したデータとV偏波を受信したデータには時間差が生じる.このようなスイッチ切り替え型偏波レーダーを用いて移動するターゲットを測定すると,受信時の時間差による影響で正しい散乱行列を得ることができない.本来はスイッチ切り替え時間に要する時間を無くし,同時に2×2の散乱行列が取得できれば望ましい.我々は遅延線を用いてほぼ同時に散乱行列を取得できる偏波レーダーシステムを考案した.本文ではこの遅延線型偏波レーダーを用いて移動するターゲットの散乱行列を取得し,スイッチ型偏波レーダーで取得した散乱行列と比較を行った.また取得したデータを四成分電力分解することにより,遅延線型偏波レーダーシステムの有効性を確認した.

CiNii Article

CiNii Books

researchmap

Classification of terrain by implementing the correlation coefficient in the circular polarization basis using X-band POLSAR data 査読

Yoshio Yamaguchi, Yukari Yamamoto, Hiroyoshi Yamada, Jian Yang, Wolfgang-Martin Boerner

IEICE TRANSACTIONS ON COMMUNICATIONS E91B ( 1 ) 297 - 301 2008年1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

Classification of terrain is one of the most important applications of Polarimetric Synthetic Aperture Radar (POLSAR) image analysis. This paper presents a simple method to classify terrain by the use of the correlation coefficients in the circular polarization basis together with the total power of the scattering matrix in the X-band. The reflection symmetry condition that the co-polarized and the cross-polarized correlations are close to zero for natural distributed scatterers is utilized to extract characteristic parameters of small forests or cluster of trees, and oriented urban building blocks with respect to the direction of the radar illumination. Both of these kinds of scatterers are difficult to identify in high resolution POLSAR images of complex urban areas. The indices employed here are the correlation coefficient, a modified coefficient normalized by the reflection symmetric conditional case, and the total power. It is shown that forest areas and oriented building blocks are easily detected and identified. The terrain classification yielded by these combinations is very accurate as confirmed by photographic ground truth images.

DOI： 10.1093/ietcom/e91-b.1.297

Web of Science

researchmap

Polarimetric scattering model decomposition for Pol-InSAR data 査読

H. Yamada, Y. Yamaguchi, R. Sato

International Geoscience and Remote Sensing Symposium (IGARSS) 4 ( 1 ) IV331 - IV334 2008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）

This paper presents scattering model decomposition technique with Pol-InSAR datasets. The target model decomposition based on the scattering mechanisms corresponding to surface, double, and volume scattering, is one of the powerful tools to analyze and classify the ground surface conditions with fully polarimetric SAR data. However, we sometimes meet difficulty that the power of the decomposed component(s) becomes negative. This is caused by assumptions in the decomposition technique. When a Pol-InSAR dataset is available, additional observables can be obtained. These new observables will be available to resolve the difficulty of negative power in the conventional decomposition technique. In this paper, we consider the scattering model decomposition technique with Pol-InSAR data, and propose some modifications for the decomposition. © 2008 IEEE.

DOI： 10.1109/IGARSS.2008.4779725

Scopus

researchmap

Polarimetric scattering analysis for simplified man-made structure model on rough and/or inclined ground plane 査読

Ryoichi Sato, Yoshio Yamaguchi, Hiroyoshi Yamada

International Geoscience and Remote Sensing Symposium (IGARSS) 4 ( 1 ) IV483 - IV486 2008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）

This paper analytically examines polarimetric scattering for a simplified man-made structure model, by utilizing the Finite- Difference Time-Domain (FDTD) method. The model considered here simulates a building in mountainous environment and is composed of a dielectric rectangular parallelepiped on finite rough and/or inclined plate. The statistical FDTD analysis on two polarimetric indices, the scattered power decomposition and the polarimetric correlation coefficient, with respect to squint angle change is carried out. It is found from the detailed analysis that the considered polarimetric indices are valid even when the surface of the ground plate has small roughness and gentle slope. This result contributes to the development of Polarimetric Synthetic Aperture Radar (POLSAR) image analysis for detecting or classifying man-made residential houses in mountainous region. © 2008 IEEE.

DOI： 10.1109/IGARSS.2008.4779763

Scopus

researchmap

Seasonal change monitoring of wetlands by using airborne and satellite polsar sensing 査読

Ryoichi Sato, Yoshio Yamaguchi, Hiroyoshi Yamada, Wolfgang-Martin Boerner

International Geoscience and Remote Sensing Symposium (IGARSS) 2 ( 1 ) II289 - II292 2008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）

This paper presents a simple water area classification technique based on POLSAR image analysis and investigates the seasonal change of the true water area in wetland by making use of the satellite ALOS/PALSAR data, in addition to the air-borne. Pi-SAR data. We here utilize the scattering power decomposition method in the image analysis, and verify that the double-bounce scattering, which can be considered as a true water area classification marker, is observed from the wetland and the surrounding emerged plants for both the airborne and satellite POLSAR data sets, even though the resolution and the incident angle are quite different, The dependency of the polarimetric scattering feature on the variation of the incident angle is also investigated by the polarimetric scattering analysis for a simplified emergent-water boundary model by using the Finite-Difference Time-Domain (FDTD) method. It is resultantly confirmed that the double-bounce scattering is utilized as a useful marker for the distinction of the true water area of the wetland even for small incident angle case. © 2008 IEEE.

DOI： 10.1109/IGARSS.2008.4778984

Scopus

researchmap

The bank-overlapped post-Doppler method and its system design for self-developed parallel processing boards 査読

J. Suzuki, H. Yamada, Y. Yamaguchi, M. Tanabe

2008 IEEE Radar Conference, RADAR 2008 2008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）

Post-Doppler methods are rank reduction techniques to reduce temporal dimensions by applying the Doppler filter and can reduce the processing time than full degrees-of-freedom (DOF) space-time adaptive processing (STAP). In post-Doppler methods, multi-bin post-Doppler methods are generally used to improve the performance of signal-to-interference-plus-noise ratio (SINR). However, it is necessary to solve the issue of different adaptation for each Doppler bin by using the covariance matrices which formed by multiple filter banks. Therefore, it is very effective to calculate each optimum weight in parallel. For further improvements of processing time, we propose an efficient approach to calculate not one but multiple Doppler bins. When a uniform filter weight is applied to the proposed method, the performance of SINR deteriorate in the vicinity of bank edges. Therefore, we improved the performance by overlapping in the filter bank of both ends. In addition, we show its system design and benchmark results by using self-developed digital signal processor (DSP) boards. © 2008 IEEE.

DOI： 10.1109/RADAR.2008.4720941

Scopus

researchmap

POLSAR画像解析を基とした新潟県中越地震の被災住宅の検出

佐藤亮一, 山口芳雄, 山田寛喜

第520回電波研連F分科会 2007年12月

複数給電型パラサイトアレーを用いた適応指向性制御方式の検討

森下雅透, 山田寛喜, Chen Sun, 太郎丸真, 大平孝

電子情報通信学会技術研究報告 AP2007-102 ( 11 ) 1 - 6 2007年11月

記述言語：日本語出版者・発行元：一般社団法人電子情報通信学会

適応指向性制御を行うDBF(digital beamforming)アレーはRF回路を複数(アンテナ素子と同数)系統備えているため,回路規模や消費電力などが増大するという問題がある.この問題を解決するために,素子の一部をハードウェア構成の容易な素子とした複数給電型パラサイトアレー(MuPAR: multiport parasitic array radiator)アンテナが提案されている.筆者らはこのアンテナを用いた適応指向性の制御方法として,アナログ制御とディジタル制御を組み合わせた適応制御能力について検討を行ってきた.最急勾配法による通常の適応制御では,勾配を辿り最適解を追求することに比較的多くの制御を有するため収束に時間を要した.本稿では,制御処理前にアナログ制御の適切な初期パラメータ選択を行い,その後,制御アルゴリズムにより制御を行うことで収束特性の高速化を図る手法について検討を行った.

CiNii Article

CiNii Books

researchmap

Pol-InSAR画像解析におけるESPRIT法を用いた散乱モデル分解法の精度向上

小野田仁, 山田寛喜, 山口芳雄

電子情報通信学会技術研究報告 AP2007-99 ( 10 ) 69 - 74 2007年10月