A Novel Fss With Ultra-wideband Polarization Selective Response

7/27/2019 A Novel Fss With Ultra-wideband Polarization Selective Response

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A Novel Frequency Selective Surface with

Ultra-Wideband Polarization Selective ResponseWan-lu Li, Guo-hui Yang, Tong Zhang, Qun Wu

School of Electronics and Information Technology

Harbin Institute of Technology

No. 92 Xidazhi Street

Harbin, Heilongjiang Province, China 150001

Abstract - A novel frequency selective surface (FSS) with

ultra-wideband (UWB) polarization selective response is proposed,

in which a unit cell consists of two metallic plane of a novel

asymmetry pattern. Simulation results prove that the FSS can

realize selectivity of waves of a certain polarization with the

bandwidth more than 36.5%, and for different incident angles the

bandwidth can be broader. Moreover, effects of parameters of the

structure on transmission performances of the FSS are researched

and conclusions are presented, which provides theoretical basis

for practical application.

I. INTRODUCTION

Frequency selective surfaces (FSS) are planar periodic arrays

of metal patches or slots that function as filtering elements for

free-space radiation [1] – [4]. Their shape and dimensions as

well as the substrate characteristics determine the performance

of an FSS structure and they are selected and optimized

according to different specifications. FSSs are widely used as polarizers, space filters, subreflectors in dual frequency

antennas and as radomes for radar cross section (RCS)

controlling [5]. One of the significant applications, polarizers,

is by making use of a special characteristic of

FSS — polarization selectivity. Based on this property

polarization-selective filtering element can be made up and

used in many fields, such as so-called filtennas combining an

antenna with a filtering shield in a single unit [6], and it can be

employed in quasi-optical systems requiring a separation of

polarization, such as it is the case e.g., in polarimetric imaging

radars and/or radiometers [7].

In this paper, a novel band-reject FSS with UWB

polarization selective response is proposed. Simulation by

CST Microwave Studio presents that for normal incident

waves the bandwidth of polarization selectivity band is

about 36.5%, while for oblique incident waves the

bandwidth is wider. In addition, the bandwidth and starting

frequencies of the polarization selectivity band can be

adjusted by changing parameters of the structure, which proves

the practicability of the proposed FSS.

II. FSS STRCTURE AND ITS PERFORMANCES

To realize a linear polarization selective surface, thestructure is designed as Fig.1 shows. Unlike conventional FSS

pattern, such as cross-line structure or rectangle structure, this

pattern is designed to be asymmetry to realize the polarization

selectivity. As Fig.1 shows, two metallic layers of the novel

asymmetry pattern are placed on top and bottom side of the

dielectric substrate. The pattern mainly consists of three

semi-circles with a co-edged point. On the side of the radius,

the semi-circles are cut by a triangle, of which the vertex is

also the edge point of the semi-circles. Therefore, the

connected part forms a large inductance, while the gap part

forms a capacitance. Moreover, compared with single-circle

structure, this multi-circle structure improves bandwidth of the

FSS. Structure of the periodic array of the FSS is shown in

Fig.2.

To testify the polarization-selective performance of the

proposed FSS, simulation is conducted with all the parameters

are defined as follows: thickness of the dielectric substrate

h=2mm, relative dielectric constant of the substrate εr =2.2,

thickness of the metal strips t =0.2mm, outer radius of thesemi-circles r =3mm, radius difference of the semi-circles

y=d =0.3mm, apex angle of the cutting triangle α=45⁰, and

distance between adjacent two semi-circles g =0.3mm.

Transmission performances of the FSS when illuminated by

normal incident waves are shown in Fig.3.



a ) T o p v i e w

b ) S i d e v i e w

F i g . 1 S t r u c t u r e o f t h e p r o p o s e d F S S

F i g . 2 S t r u c t u r e o f t h e p e r i o d i c a r r a y

F i g . 3 T r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S w h e n i l l u m i n a t e d b y n o r m a l

i n c i d e n t w a v e s

F r o m F i g . 3 i t c a n b e o b s e r v e d t h a t f o r T E - p o l a r i z e d w a v e s

t h e r e a r e t w o r e s o n a n t f r e q u e n c i e s b e t w e e n f r e q u e n c y b a n d s

0 - 1 5 G H z , a n d f o r t h e r e j e c t p e r f o r m a n c e b a n d o f w h i c h t h e

i m p e d a n c e i s m o r e t h a n 2 0 d B t h e b a n d i s f r o m 8 . 2 2 G H z t o

1 1 . 8 9 G H z , w i t h 3 . 6 7 G H z b a n d w i d t h . S i n c e i m p e d a n c e o f t h i s

b a n d f o r T M - p o l a r i z e d w a v e s i s n o m o r e t h a n 3 d B , t h i s

f r e q u e n c y b a n d p r e s e n t s g r e a t p o l a r i z a t i o n s e l e c t i v i t y

c h a r a c t e r i s t i c . T h e r e f o r e , s i n c e t h e c e n t e r f r e q u e n c y o f t h e

p o l a r i z a t i o n s e l e c t i v i t y b a n d i s 1 0 . 0 5 5 G H z , i t c a n b e c o n c l u d e d

t h a t t h e b a n d w i d t h o f t h e F S S f o r n o r m a l i n c i d e n t w a v e s i s

a b o u t 3 6 . 5 0 % .

S i n c e c h a r a c t e r i s t i c s o f a g r e a t F S S s h o u l d b e s t a b l e w i t h

r e s p e c t t o w a v e s o f d i f f e r e n t i n c i d e n t a n g l e s , s i m u l a t i o n f o r

w a v e s o f 3 0 ⁰ a n d 6 0 ⁰ i n c i d e n t a n g l e i s c o n d u c t e d a n d r e s u l t s

a r e p r e s e n t e d i n F i g . 4 . I t c a n b e o b s e r v e d t h a t w i t h t h e i n c r e a s e

o f i n c i d e n t a n g l e , s t a r t i n g f r e q u e n c y o f t h e p o l a r i z a t i o n s e l e c t i v i t y b a n d d e c r e a s e s , w h i l e e n d i n g f r e q u e n c y o f t h e b a n d

i n c r e a s e s . A s a r e s u l t , b a n d w i d t h o f t h e p o l a r i z a t i o n s e l e c t i v i t y

b a n d i n c r e a s e s . W h i l e f o r n o r m a l i n c i d e n t w a v e s t h e b a n d w i d t h

i s 3 6 . 5 0 % , f o r o b l i q u e i n c i d e n t w a v e s i t r i s e s u p t o 3 8 . 1 4 % a n d

4 5 . 9 6 % . T h u s , t h e F S S p r e s e n t s e x c e l l e n t p o l a r i z a t i o n

s e l e c t i v i t y c h a r a c t e r i s t i c f o r w a v e s o f d i f f e r e n t i n c i d e n t a n g l e s .

F i g . 4 T r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S w h e n i l l u m i n a t e d

b y w a v e s o f d i f f e r e n t i n c i d e n t a n g l e s

I I I . P A R A M E T E R S ’ E F F E C T S

A . O u t e r r a d i u s

S i n c e o u t e r r a d i u s d e t e r m i n e s t h e d i m e n s i o n o f t h e u n i t c e l l

o f t h e F S S , i t h a s a l a r g e e f f e c t o n i t s r e s o n a n t f r e q u e n c y a n d

b a n d w i d t h . T h e r e f o r e , w h i l e a l l t h e o t h e r p a r a m e t e r s a r e k e p t t o

b e t h e s a m e , t r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S w i t h

d i f f e r e n t o u t e r r a d i u s a r e s i m u l a t e d , a n d r e s u l t s a r e s h o w n i n



F i g . 5 . I t c a n b e o b s e r v e d t h a t t h e i n c r e a s e o f o u t e r r a d i u s

r e s u l t s i n m i n i a t u r i z a t i o n o f b o t h o f t h e r e s o n a n t f r e q u e n c i e s ,

a n d t h e r e f o r e b o t h t h e s t a r t i n g f r e q u e n c y a n d e n d i n g f r e q u e n c y

o f t h e p o l a r i z a t i o n s e l e c t i v i t y b a n d a r e m i n i a t u r i z e d . I t c a n b e

o b s e r v e d t h a t w h i l e t h e o u t e r r a d i u s o f t h e F S S i n c r e a s e f r o m

2 . 5 m m t o 3 . 0 m m a n d 3 . 5 m m , s t a r t i n g f r e q u e n c y o f t h e

p o l a r i z a t i o n s e l e c t i v i t y b a n d c h a n g e s f r o m 1 0 . 0 7 G H z t o

8 . 2 2 G H z a n d 6 . 8 8 G H z , a n d e n d i n g f r e q u e n c y c h a n g e s f r o m

1 4 . 5 2 G H z t o 1 1 . 8 9 G H z a n d 9 . 9 5 G H z . H o w e v e r , t h e

b a n d w i d t h s f o r e a c h s i t u a t i o n a r e 3 6 . 1 9 % , 3 6 . 5 0 % a n d 3 6 . 4 8 % ,

w i t h r e a l l y l i m i t e d v a r i e t y . T h u s b y a d j u s t i n g t h e o u t e r r a d i u s

o f t h e F S S t h e s t a r t i n g a n d e n d i n g f r e q u e n c i e s o f t h e

p o l a r i z a t i o n s e l e c t i v i t y b a n d c a n b e m o d u l a t e d , w h i l e

b a n d w i d t h s t a y s t h e s a m e .

F i g . 5 T r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S s w i t h d i f f e r e n t o u t e r r a d i u s e s

w h e n i l l u m i n a t e d b y n o r m a l i n c i d e n t w a v e s

B . R a d i u s d i f f e r e n c e

T o i n v e s t i g a t e e f f e c t s o f r a d i u s d i f f e r e n c e o f t h e F S S ,

t r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S s w i t h d i f f e r e n t r a d i u s

d i f f e r e n c e s w h i l e k e e p i n g t h e o u t e r r a d i u s t h e s a m e i s

s i m u l a t e d a n d t h e r e s u l t s a r e p r e s e n t e d i n F i g . 6 . I t c a n b e

o b s e r v e d t h a t w i t h t h e i n c r e a s e o f r a d i u s d i f f e r e n c e , b o t h t h e

s t a r t i n g a n d t h e e n d i n g f r e q u e n c y o f t h e p o l a r i z a t i o n s e l e c t i v i t y

b a n d i n c r e a s e . S i m i l a r w i t h e f f e c t s o f o u t e r r a d i u s , b a n d w i d t h

o f t h e F S S d o e s n o t c h a n g e w i t h v a r i a t i o n o f r a d i u s d i f f e r e n c e .

F o r t h e F S S w i t h r a d i u s d i f f e r e n c e 0 . 3 m m , 0 . 4 m m a n d 0 . 5 m m ,

t h e b a n d w i d t h i s a b o u t 3 6 . 5 0 % , 3 6 . 4 7 % a n d 3 6 . 6 5 % . T h e r e f o r e

c h a n g i n g t h e r a d i u s d i f f e r e n c e c a n a l s o b e u s e d t o a d j u s t t h e

v a l u e s o f s t a r t i n g a n d e n d i n g f r e q u e n c i e s o f t h e F S S w h i l e

k e e p i n g t h e b a n d w i d t h t h e s a m e .

F i g . 6 T r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S s w i t h d i f f e r e n t r a d i u s d i f f e r e n c e s


C . C u t t i n g a n g l e

S i n c e t h e a n g l e o f t h e c u t t i n g t r i a n g l e d i r e c t l y d e t e r m i n e s t h e

c u t t i n g l e n g t h o f e a c h s e m i - c i r c l e , a n d t h e r e f o r e d e t e r m i n e s

e q u i v a l e n t i n d u c t a n c e a n d c a p a c i t a n c e o f e a c h p a r t ,

t r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S w i t h d i f f e r e n t c u t t i n g

a n g l e i s r e s e a r c h e d , a n d r e s u l t s a r e s h o w n i n F i g . 7 . I t c a n b e

o b s e r v e d t h a t w i t h t h e i n c r e a s e o f c u t t i n g a n g l e , b o t h t h e

s t a r t i n g a n d e n d i n g f r e q u e n c i e s o f t h e p o l a r i z a t i o n s e l e c t i v i t y

b a n d a r e i n c r e a s e d . B u t u n l i k e t h e o t h e r t w o p a r a m e t e r s ’ e f f e c t s ,

c u t t i n g a n g l e s a l s o h a s e f f e c t s o n b a n d w i d t h o f t h e p o l a r i z a t i o n

s e l e c t i v i t y b a n d . W i t h t h e c u t t i n g a n g l e i n c r e a s e s f r o m 3 0 ⁰ t o

4 5 ⁰

a n d 6 0 ⁰

, t h e b a n d w i d t h i n c r e a s e s f r o m 3 1 . 3 4 % t o 3 6 . 5 0 % a n d 4 0 . 5 6 % . T h u s , b y i n c r e a s i n g t h e c u t t i n g a n g l e t h e

b a n d w i d t h o f t h e p o l a r i z a t i o n s e l e c t i v i t y b a n d c a n b e f u r t h e r

b r o a d e n e d .

F i g . 7 T r a n s m i s s i o n p e r f o r m a n c e s o f t h e F S S s w i t h d i f f e r e n t c u t t i n g a n g l e s




I V . C O N C L U S I O N

I n t h i s p a p e r , a n o v e l b a n d - r e j e c t F S S w i t h U W B

p o l a r i z a t i o n s e l e c t i v i t y r e s p o n s e i s p r o p o s e d . B y t h e u t i l i z a t i o n

o f t h e n o v e l p a t t e r n m o d i f i e d f r o m f r a c t a l s e m i - c i r c l e s t h e F S S

c a n r e a l i z e a w i d e p o l a r i z a t i o n s e l e c t i v i t y b a n d w i t h t h e

b a n d w i d t h m o r e t h a n 3 6 . 5 % f o r n o r m a l i n c i d e n t w a v e s , a n d f o r o b l i q u e t h e b a n d w i d t h i s b r o a d e r . I n a d d i t i o n , b o t h t h e s t a r t i n g

a n d e n d i n g f r e q u e n c i e s a n d b a n d w i d t h o f t h e F S S c a n b e

a d j u s t e d b y m o d u l a t i n g t h e t h r e e p a r a m e t e r s o f t h e s t r u c t u r e :

o u t e r r a d i u s , r a d i u s d i f f e r e n c e a n d c u t t i n g a n g l e . T h u s t h e

p r o p o s e d F S S h a s a p r o m i s i n g f u t u r e i n p r a c t i c a l a p p l i c a t i o n

f o r a n t e n n a a n d r a d a r s y s t e m s .

A C K N O W L E D G M E N T

T h e a u t h o r s w o u l d l i k e t o e x p r e s s t h e i r s i n c e r e g r a t i t u d e t o

C S T L t d . G e r m a n y , f o r p r o v i d i n g t h e C S T T r a i n i n g C e n t e r

( N o r t h e a s t C h i n a R e g i o n ) a t o u r u n i v e r s i t y w i t h a f r e e p a c k a g e

o f C S T M W S s o f t w a r e .

T h i s w o r k w a s s u p p o r t e d b y t h e N a t i o n a l N a t u r a l S c i e n c e

F o u n d a t i o n o f C h i n a u n d e r G r a n t 6 0 8 0 1 0 1 5 a n d 6 1 0 0 1 0 3 6 .

R E F E R E N C E S

[ 1 ] T . K . W u , F r e q u e n c y S e l e c t i v e S u r f a c e a n d G r i d A r r a y . N e w Y o r k : W i l e y ,

1 9 9 5 .

[ 2 ] J . C . V a r d a x o g l o u , F r e q u e n c y S e l e c t i v e S u r f a c e s . N e w Y o r k : W i l e y ,

1 9 9 7 .

[ 3 ] B . A . M u n k , F r e q u e n c y S e l e c t i v e S u r f a c e s : T h e o r y a n d D e s i g n . N e w

Y o r k : W i l e y I n t e r s c i e n c e , 2 0 0 0 .

[ 4 ] R . M i t t r a , C . H . C h a n , a n d T . C w i k , “ T e c h n i q u e s f o r a n a l y z i n g

f r e q u e n c y s e l e c t i v e s u r f a c e s — A r e v i e w , ” P r o c . I E E E , v o l . 7 6 , D e c . 1 9 8 8 ,

p p . 1 5 9 3 – 1 6 1 5

[ 5 ] G u o Q i n g L u o , W e i H o n g , Z h a n g - C h e n g H a o , B i n g L i u , W e i D o n g L i , J i

X i n C h e n , H o u X i n g Z h o u , a n d K e W u , T h e o r y a n d E x p e r i m e n t o f N o v e l

F r e q u e n c y S e l e c t i v e S u r f a c e B a s e d o n S u b s t r a t e I n t e g r a t e d W a v e g u i d e

T e c h n o l o g y , I E E E T r a n s a c t i o n s O n A n t e n n a s a n d P r o p a g a t i o n , v o l . 5 3 ,

n o . 1 2 , D E C E M B E R 2 0 0 5 , p p . 4 0 3 5 - 4 0 4 3

[ 6 ] J . E . R o y a n d L . S h a f a i , “ R e c i p r o c a l c i r c u l a r - p o l a r i z a t i o n - s e l e c t i v e

s u r f a c e , ” I E E E A n t e n n a s P r o p a g a t i o n , v o l . 3 8 , n o . 6 , D e c . 1 9 9 6 , p p .

1 8 – 3 3

[ 7 ] W i n k l e r , S . A . , H . W e i , e t a l . “ P o l a r i z a t i o n R o t a t i n g F r e q u e n c y S e l e c t i v e

S u r f a c e B a s e d o n S u b s t r a t e I n t e g r a t e d W a v e g u i d e T e c h n o l o g y . ”

A n t e n n a s a n d P r o p a g a t i o n , I E E E T r a n s a c t i o n s o n 5 8 ( 4 ) : 1 2 0 2 - 1 2 1 3 .

A Novel Fss With Ultra-wideband Polarization Selective Response

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