fundamentals of array antenna

Fundamentals of Array Antenna

Antenna Antenna EngineeringEngineering

CHO, Yong HeuiCHO, Yong Heui

Antenna Antenna EngineeringEngineering

EM Wave LabEM Wave Lab2

Array antenna

1. Introduction

High gain antenna

Linear array Planar array Conformal array: nonplanar surface, aircraft Phased array

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Microstrip patch antenna

1. Introduction

Single patch antenna

Linear array: series feedingPlanar array: parallel feeding

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Conformal array antenna

1. Introduction

Conformal array: microstrip patch and cavity (Alcatel)

Spot beam of LEO satellite

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Two-element array

2. Array antenna

AF (Array Factor): far field

cos

22

11

21

1ˆsin4

ˆsin4

ˆsin4

21

jkdjkr

jkrjkr

t

ejkr

zeI

jkr

zeIjk

r

zeI

EEE

cos

2cos21AF cos2/cos kd

ee jkdjkd

cos , 21 drrrr

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EM Wave LabEM Wave Lab6

Array factor

2. Array antenna

AF and element factor Maximum value of AF:

)2/sin(

)2/sin(

1

1

1AF

2/)1(1

0

)1(2

Ne

e

ee

eee

Njj

jNN

n

jn

Njjj

0at N

)2/sin(

)2/sin()(

N

Nf

coskd

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Active integrated antenna

3. Active antenna

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Receiving module for active antenna

3. Active antenna

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Self structuring antenna

3. Active antenna