VHF - - PowerPoint PPT Presentation

船舶に搭載したVHFレーダーによる 表層流計測の可能性について

ー方位推定に対する影響の検証ー 佐地 健太郎1, 新井 励2, 中谷 直樹2, 山田 智貴2, 奥野 武俊2 , 濱野 哲也3

1Graduate Student of Osaka Prefecture University 2 Osaka Prefecture University 3 Kawasaki Shipbuilding Corporation

Flow field Flow field

introduction introduction

safe and efficient sailing environmental phenomena salt temperature nutrient …etc

introduction introduction

Metallic ship hull Metallic ship hull ↓ ↓ Radio wave Radio wave Flow field Flow field

VHF radar VHF radar

Flow field Flow field near the coast near the coast in the ocean in the ocean

VHF radar VHF radar

VHF radar VHF radar Produced by CODAR Produced by CODAR

Compact size Compact size 3 antennas 3 antennas

Estimation of arrival direction Estimation of arrival direction

I t t AF t X

2

) ( ) ( ) (   

     

L

a a A   , ,

1 



Ｘ：received signal value Ｆ：intensity of the arrival radio wave σ2I： noise vector

Ａ：directivity characteristic θ：arrival direction

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

antenna1 antenna2

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

antenna1 antenna2

Estimation of arrival direction Estimation of arrival direction

t： score e： eigen vector s: signal N: noise

) ( ) ( t X t X R

H xx 

：covariance matrix of X

2 2 1

          

K L L

 

noise noise signal signal

eN :eigen vector

N n S S

e t e t e t t X     

2 2 1 1

) (

directive component directive component

N S

e e 

     

L

a a A   , ,

1 



) (

L



N H e

a 

inner product: inner product:

arrival direction arrival direction

Estimation of arrival direction Estimation of arrival direction

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 180 210 240 270 300 330 360 azimuth direction θ Music spectrum P

MU

position of peak position of peak

) (

L



N H e

a 

∴ ∴ inner product: inner product:



 | ) ( | 1 ) (   a e P

H i MU

P : directive function （MUSIC spectrum）

Arrival direction Arrival direction ＭＵＳＩＣ ＭＵＳＩＣ algorism algorism

MUltiple MUltiple SIgnal SIgnal Classification Classification

Antenna pattern Antenna pattern

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern antenna1 antenna2

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern antenna1 antenna2

巨大な構造物 巨大な構造物 ・ ・島 島 ・ ・山 山 ・ ・橋 橋 ・ ・建物 建物… …etc etc 金属 金属 ・ ・鉄 鉄 ・ ・銅 銅… …etc etc アンテナパターンを歪める物体 アンテナパターンを歪める物体

θ θ

The measurement method of Antenna pattern The measurement method of Antenna pattern

50m 50m

antenna1 antenna2

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

The measurement method of Antenna pattern The measurement method of Antenna pattern

transponder transponder VLCC VLCC workboat workboat GPS GPS gyro gyro GPS GPS

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

Result Resultｓ ｓ

funnel upper deck wing wing Head of VLCC Head of VLCC

Estimation of the arrival direction Estimation of the arrival direction

transponder transponder VLCC VLCC workboat workboat transponder transponder transponder transponder VLCC VLCC workboat workboat

GPS GPSによって算出した によって算出した 正確な方位 正確な方位 MUSIC MUSICアルゴリズムによる アルゴリズムによる 到来方向の推定結果 到来方向の推定結果

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 180 210 240 270 300 330 360 azimuth direction θ Music spectrum P

MU

MUSIC algorism MUSIC algorism 比較 比較

Results of MUSIC Results of MUSIC

60 120 180 240 300 360 60 120 180 240 300 360 correct direction estimate direction y=x estimated results

90 90 190 190 270 270 330 330 direction of structure direction of structure

(4,171) (4,171)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 60 120 180 240 300 360 azimuth direction θ MUSIC Sspectrum P

MU

171 171 6 6

60 120 180 240 300 360 60 120 180 240 300 360 correct direction estimate direction y=x estimated results

Results of MUSIC

265 265 275 275 325 325 360 360 85 85 190 190

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

A P

(4,171) (4,171)

Results of MUSIC Results of MUSIC

60 120 180 240 300 360 60 120 180 240 300 360 correct direction estimate direction y=x estimated results

60 120 180 240 300 360 60 120 180 240 300 360 correct direction estimate direction y=x estimated results

before before (4,171) (4,171) (4,6) (4,6)

Results of MUSIC Results of MUSIC

60 120 180 240 300 360 60 120 180 240 300 360 correct direction estimate direction y=x estimated results

60 120 180 240 300 360 60 120 180 240 300 360 correct direction estimate direction y=x estimated results

before before (4,171) (4,171) (4,6) (4,6)

構造物からどの程度の距離を離 構造物からどの程度の距離を離 して，アンテナを設置する必要が して，アンテナを設置する必要が あるのか？？ あるのか？？

The experiment of the obstacles The experiment of the obstacles

Rinku Rinku Park Park

The experiment of the obstacles The experiment of the obstacles

case2 case3

Case 1 no obstacles around the antennas Case 2 a car placed 3.5 meter away from antennas Case 3 a car placed 7.0 meter away from antennas

VHF VHF電波の約 電波の約1 1波長 波長

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case1

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case2

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case3

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case1

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case1

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case2

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case2

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case3

1.000 0.500 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Radiation Pattern

antenna1 antenna2

case3

Results of measuring antenna patterns Results of measuring antenna patterns

3.5 3.5ｍ ｍ 7.0 7.0ｍ ｍ no obstacles no obstacles

The direction The direction

• f obstacles
• f obstacles

Estimation of arrival direction Estimation of arrival direction

240 260 280 300 320 340 360 240 260 280 300 320 340 360 correct direction estimate direction y=x-5 y=x y=x+5 case1 case2 case3

Estimation of arrival direction in case1 Estimation of arrival direction in case1

240 260 280 300 320 340 360 240 260 280 300 320 340 360 correct direction estimate direction y=x-5 y=x y=x+5 case1

Estimation of arrival direction in case 2 Estimation of arrival direction in case 2 – – 4 4

240 260 280 300 320 340 360 240 260 280 300 320 340 360 correct direction estimate direction y=x-5 y=x y=x+5 case2 case3

conclusions conclusions

船舶搭載時の 船舶搭載時の ・アンテナパターンへの影響 ・アンテナパターンへの影響 構造物の方位に大きな歪み 構造物の方位に大きな歪み ・到来方向推定への影響 ・到来方向推定への影響 アンテナパターンから歪んだ方位を除くことで アンテナパターンから歪んだ方位を除くことで 到来方向の推定が可能 到来方向の推定が可能 ・良好な設置条件 ・良好な設置条件 障害物の少ない場所に設置 障害物の少ない場所に設置 構造物から 構造物から7 7ｍ以上 ｍ以上離して設置 離して設置

Thank you very much Thank you very much for your kind attention!! for your kind attention!!

The measurement method of Antenna pattern The measurement method of Antenna pattern

mooring at the land mooring at the land Anchoring in the open sea Anchoring in the open sea transponder transponder VLCC VLCC workboat workboat GPS GPS gyro gyro GPS GPS

antenna1 antenna2

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

Measured Antenna Pattern Measured Antenna Pattern

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

Mooring At the land Mooring At the land Anchoring In the open sea Anchoring In the open sea A1 A1 A2 A2 A2 A2 A1 A1

Head of VLCC Head of VLCC

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

Antenna Pattern Antenna Pattern

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

At landing At landing In the open sea In the open sea A1 A1 A2 A2 A2 A2 A1 A1

2.0 1.0 90 60 30 330 300 270 240 210 180 150 120

Angle(degree)

Antenna Pattern

Result Result

In the open sea In the open sea

introduction introduction

Point measurement Point measurement Line measurement Line measurement Plane measurement Plane measurement

Magnetic velocity meter Magnetic velocity meter Acoustic Doppler Current Profiler Acoustic Doppler Current Profiler

VHF radar VHF radar

conclusions conclusions

・ ・ the steel ship hull distorts strongly the antenna the steel ship hull distorts strongly the antenna pattern pattern ・ ・if the extremely strained region is removed from the if the extremely strained region is removed from the antenna pattern, antenna pattern, it is possible to correctly it is possible to correctly estimate the arrival directions of the radio waves in estimate the arrival directions of the radio waves in particular region. particular region. I examined I examined the influence upon the antenna pattern the influence upon the antenna pattern and the correct estimation of arrival direction. and the correct estimation of arrival direction.

however however