7/27/2019 Missile Mounted Waveguide Antenna

1/5

United S t a t e s Patent [ 1 9 ] [ 1 1 ] P a t e n t N u m b e r : 4 , 5 7 7 , 1 9 6Yu [ 4 5 ] D a t e o f P a t e n t : Mar. 1 8 , 1 9 8 6[ 5 4 ] MISSILE MOUNTEDWAVEGUIDE 2 5 0 6 5 2 5 1 1 / 1 9 8 2 F r a n c e .

ANTENNA 5 6 - 4 9 0 2 1 / 1 9 8 1 . l a p a n .938146 10/1963 United Kingdom .[ 7 5 ] I n v e n t o r : I - P i n g Y u , T h o u s a n d O a k s , C a l i f ._ OTHERPUBLICATIONS

[ 7 3 ] A s s i g n e e z Hughes A i r c r a f t Company, E1 , IS e g u n d o , C a l i f W a l t o n e t 2 1 1 . , B r o a d Band R i d g e d Horn D e s i g n , TheMicrowave J o u r n a l , v o l . 7 , N o . 3 , M a r . 1 9 6 4 , p p . 9 6 , 9 7 ,[ 2 1 ] A p p l . N O . : 4 8 1 , 5 0 1 9 9 4 0 1 .[ 2 2 ] F i l e d : A p r 1 1 9 8 3 P r i m a r y E x a m i n e r - E l i L i e b e r m a n[ 5 1 ] I n t . C l . 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOlQ 13/06 A s s i s t a n t Examiner-Michael C. Wimer .[ 5 2 ] U . S . C l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4 3 / 7 0 5 ; 343/772 A t t o r n e y . A g e n t . o r FirmCharlcs D. Brown; Michael[ 5 8 ] F i e l d o f S e a r c h . . . . . . . . . . . . . . . . 3 4 3 / 7 7 2 , 7 7 6 , 7 8 2 - 7 8 6 , W- S a l e s ; Anthony W- Karambclas

3 4 3 / 7 0 5 , 7 1 1 , 7 0 8 [ 5 7 ] ABSTRACT[ 5 6 ] R e f e r e n c e s C l t e d A e n e r a l l y r e c t a n g u l a r w a v e g u i d e a n t e n n a h a s two

U . S . PATENT DOCUMENTS narrow s i d e w a l l s connected t o t w o broad w a l l s . On e o f2 , 4 2 3 , 0 7 3 6/1947 Willoughby . . . . . . . . . . . . . . . . . . . . . . . . 343/772 the b roa d Walls t a k e s th e form of a conventional r e c t a n '2 , 8 1 0 , 9 0 7 1 0 / 1 9 5 7 _ _ 3 4 3 / 7 7 1 g u l a r r i d g e d w a l l . T he o t h e r broad w a l l i S curved with3 , 3 8 0 , 0 5 7 4 / 1 9 68 3 4 3 / 7 8 6 t h e a r c o f t h e c u r v e e x t e n d i n g s u b s t a n t i a l l y t h e f u l l3 , 4 5 3 , 8 6 2 7 / 1 9 6 9 3 4 3 / 7 3 6 width of t h e w a l l . T he antenna h a s an open end a nd 2 13 , 6 5 3 , 0 5 4 1 0 / 1 9 7 04 , 1 2 4 , 8 5 1 1 1 / 1 9 7 84 , 2 4 5 , 2 2 2 l / 1 9 8 l

FOREIGN PATENT DOCUMENTS949493 9/ 1956 Fed. Rep. of Germany . . . . . 343/ 783

110 4480 l l / l 9 5 5 F r a n c e .2 4 4 5 0 42 7 / 1 9 8 0 F r a n c e .

c l o s e d e n d . T he en d o f t h e curved broad w a l l e x t e n d sb e y o n d t h e e n d o f t h e r e c t a n g u l a r r i d g e w a l l a t t h e o p e nen d of t h e antenna. T he t w o n a r r o w s i d e w a l l s a r e c u t a ta n a n g l e , a t t h e open e n d , t o j o i n t h e s h o r t e r r i d g e d w a l land t h e extended curved w a l l .

4 C l a i m s , 4 D r a w i n g F i g u r e s

7/27/2019 Missile Mounted Waveguide Antenna

2/5

U . S . P a t e n t M a r . 1 8 , I 9 8 6 S h e e t l o f Z 4 , 5 7 7 , 1 9 6

7/27/2019 Missile Mounted Waveguide Antenna

3/5

US. P a t e n t M a r . r l 8 , 1 9 8 6 S h e e t 2 0 f 2 4 , 5 7 7 , 1 9 6

7/27/2019 Missile Mounted Waveguide Antenna

4/5

4 , 5 7 7 , 1 9 61MISSILE MOUNTEDWAVEGUIDE ANTENNAThe U n i t e d S t a t e s Government h a s r i g h t s i n t h i s

i n v e n t i o n under A i r Force c o n t r a c t number F08635-82C - O O O l .

BACKGROUND OF THE INVENTION1 . F i e l d o f t h e I n v e n t i o nT h i s i n v e n t i o n r e l a t e s t o t h e ? e l d o f r i d g e d w a v e

g u i d e a n t e n n a s a n d p a r t i c u l a r l y t o d o u b l e r i d g e d w a v eg u i d e a n t e n n a s f o r microwave f r e q u e n c y communicat i o n s . The d i s c l o s e d a n t e n n a i s i n t e n d e d f o r mounting nt h e b o a t t a i l o f a m i s s i l e .

2 . P r i o r Ar tThe a r t and s c i e n c e o f d e s i g n i n g d o u b l e r i d g e d w a v eg u i d e a n t e n n a s f o r o p e r a t i o n i n t h e microwave f r equency r a n g e a r e w e l l understood f o r t h e c o n v e n t i o n a ls y m m e t r i c d o u b l e r i d g e d co n ? g u r a t i o n . E x t e n s i v e a n a ly s i s and d i s c u s s i o n a r e p r e s e n t e d i n a number o f t r a d ej o u r n a l a r t i c l e s . P e r t i n e n t b a c k g r o u n d i n f o r m a t i o n i nc l u d e s P r o p e r t i e s o f R i d g e W a v e g u i d e a p p e a r i n g i n t h eP r o c e e d i n g s o f t h e I . R . E . o f August 1 9 4 7 a t p a g e s7 8 3 - 7 8 8 a u t h o r e d b y Seymour B . C o h n . T h i s a r t i c l emakes i t c l e a r t h a t r i d g e d waveguide r e s u l t s i n a lowe r e d c u t o f f f r e q u e n c y , l o w e r e d i m p e d e n c e , a n d w i d eb a n d w i d t h f r e e f r o m h i g h - m o d e i n t e r f e r e n c e whenc o m p a r e d t o n o n r i d g e d w a v e g u i d e . The u s u a l geomet r y o f t h e r i d g e i s r e c t a n g u l a r , a l t h o u g h , a s shown i n a1 9 5 7 a r t i c l e b y J . Va n B l a d e l a n d 0 . Von Rohr J r . ,s e m i c i r c u l a r r i d g e s p r o d u c e c e r t a i n a d v a n t a g e s d e s i ra b l e i n some c i r c u m s t a n c e s . S e e S e m i c i r c u l a r R i d g e s i nR e c ta n g u l a r W a v e g u i d e s , a p p e a r i n g i n t h e A p r i l 1 9 5 7IRE T r a n s a c t i o n s on Mi c ro w a v e Theory and Techn i q u e s . S e e a l s o , On t h e C o m p l e t e E i g e n v a l u e So l ut i o n o f R i d g e d W a v e g u i d e b y J a m e s P . Montgomerya p p e a r i n g i n I E E E r a n s a c t i o n s on M icrowave Theorya n d T e c h n i q u e s , V o l . MTT-l9, N o . 6 , J u n e 1 9 7 1 a tp a g e s 5 4 7 t o 5 5 5 and p a r t i c u l a r l y FIGS. 7 and 8 whichshow n o n - s y m m e t r i c r i d g e s . A o p y o f e a c h r e f e r e n c e da r t i c l e a c c o m p a n i e s t h i s a p p l i c a t i o n .U S. P a t . N o . 4 , 2 4 5 , 2 2 2 , Dual F u n c t i o n A n t e n n a ,i s s u e d J a n . 1 3 , 1 9 8 1 t o E d w a r d E n g e t a l . shows ana n t e n n a h a v i n g a c a v i t y s h a p e s i m i l a r t o t h a t o f t h ep r e s e n t i n v e n t i o n , a s b e s t i l l u s t r a t e d i n FIG. 4 . Alt h o u g h t h e s h a p e o f t h e c a v i t y i s somewhat s i m i l a r , i tshould be noted t h a t t h e antenna i s r e f e r r e d t o a s ac i r c u m f e r e n t i a l s l o t a n t e n n a , h a v i n g s l o t s 2 2 a n d 2 4 , a n di s n o t a r i d g e d waveguide a n t e n n a . No i d g e s a r e p r e se n t i n t h e a n t e n n a o f E n g e t a l . A op y o f t h a t p a t e n ta c c o m p a n i e s t h i s a p p l i c a t i o n .

SUMMARYOF THE INVENTIONThe i n v e n t i o n c o m p r i s e s a d o u b l e r i d g e d w a v e g u i d e

antenna wherein t h e t w o r i d g e s t r u c t u r e s a r e d i s s i m i l a r .S p e c i ? c a l l y , o n e o f t h e r i d g e s i s t h e t y p i c a l r e c t a n g u l a rr i d g e , b u t t h e o t h e r r i d g e i s a n a r c u a t e r i d g e w i t h t h ea r c u a te p o r t i o n e x t e n d i n g s u b s t a n t i a l l y t h e f u l l w i d t h o ft h e b r o a d e r w a l l o f t h e w a v e g u i d e . On e e n d o f t h ewaveguide i s c l o s e d . The e n d s o f t h e narrow s i d e w a l l so f t h e open end o f t h e waveguide a r e c u t a t an a n g l e t oj o i n t h e c u r v e d b r o a d w a l l t o t h e s h o r t e r r e c t a n g u l a rr i d g e d w a l l . T h i s c o n ? g u r a t i o n p r o d u c e s a l o w - b a n dc o m p a c t a n t e n n a c a p a b l e o f ? t t i n g w i t h i n t h e l i m i t e dvolume o f t h e m i s s i l e b o a t t a i l and h a v i n g narrow bandc h a r a c t e r i s t i c s . The champhered o p e n e n d p r o v i d e s ah i g h d e g r e e o f f r e e d o m f r o m i n t e r f e r e n c e f r o m a h i g h e rf r e q u e n c y b a n d a n t e n n a l o c a t e d n e a r b y . The d i s s i m i l a r

1 5

2 5

3 5

40

45

5 5

6 5

2n a t u r e o f t h e r i d g e s a l s o p r o v i d e s f o r moderate c r o s sp o l a r i z a t i o n g a i n w h i c h i s u s e f u l i n t h e s y s t e m e n v i r o nment.

B R I E F DESCRIPTION OF THE DRAWINGSFIG. 1 i s a r e a r end view of a m i s s i l e showing t h e

p o s i t i o n o f t h e a n t e n n a i n t h e m i s s i l e b o a t t a i l .FIG. 2 i s a p e r s p e c t i v e view o f t h e d o u b l e r i d g e dw a v e g u i d e a n t e n n a .FIG. 3 i s a view o f t h e open end o f t h e waveguide

antenna.FIG. 4 i s a c r o s s s e c t i o n a l view t a k e n a l o n g t h e l i n e

4-4 o f FIG. 3 .DETAILED DESCRIPTION OF THE

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

h e r e i n i s i n t e n d e d f o r i n s t a l l a t i o n i n t h e b o a t t a i l o f am i s s i l e a s shown i n FIG. 1 . A e a r end view o f a m i s s i l e1 0 r e v e a l s a s p a c e l o c a t e d between t h e o u t e r body 1 2 o ft h e m i s s i l e a nd t h e e x i t cone 1 4 o f t h e r o c k e t motorwhich p r o p e l s t h e m i s s i l e . The a n t e n n a h a s b e e n d es i g n e d t o ? t i n t h i s somewhat l i m i t e d s p a c e . The ant e n n a 20 i s viewed a s i t s open end i n FIG. 1 .As shown i n FIG. 2 , microwave e n e r g y i s p r o v i d e dt o t h e d o u b l e r i d g e d w a v e g u i d e a n t e n n a 2 0 v i a f e e da s s e m b l y 22 l o c a t e d n e a r t h e c l o s e d end o f t h e a n t e n n a .The p r e c i s e l o c a t i o n o f t h e f e e d i s s e l e c t e d t o a c h i e v ed e s i r e d narrowband c h a r a c t e r i s t i c s . The ? r s t r i d g e o fa n t e n n a 2 0 i s t h e c o n v e n t i o n a l r e c t a n g u l a r r i d g e f o r m e di n b r o a d w a l l 2 4 . Broad w a l l 2 4 c o m p r i s e s w a l l s e gm e n t s 2 6 a n d 2 8 a n d i n c l u d e s t h e r e c t a n g u l a r r i d g e 3 0f o r m e d b y g e n e r a l l y p a r a l l e l s i d e w a l l s e g m e n t s 3 2 a n d3 4 a n d p e r p e n d i c u l a r r i d g e w a l l 3 6 . The s e c o n d r i d g e o fa n t e n n a 2 0 i s t h e a r c u a t e r i d g e 3 8 which f o r m s t h e opp o s i t e b r o a d w a l l . A r c u a t e r i d g e 3 8 m o s t c l o s e l y a pp r o a c h e s r i d g e w a l l 3 6 n e a r i t s m i d p o i n t a n d d e f i n e s ag a p 4 0 shown b e s t i n FIGS. 3 a n d 4 . P e r p e n d i c u l a r t ot h e t w o broad w a l l s a r e t h e t w o opposed narrow s i d ew a l l s 42 and 4 4 .An e l e v a t i o n a l view o f t h e open e n d o f t h e r i d g e d

waveguided 2 0 s shown n FIG. . The a r c u a t e r i d g e 3 8i s shown e x t e n d i n g t h e f u l l w i d t h o f t h e a n t e n n a 2 0 .Wall s e g m e n t s 2 6 and 2 8 a r e g e n e r a l l y p a r a l l e l t o t h ea r c u a t e r i d g e 3 8 , a l t h o u g h t h e w a l l s e g m e n t s 2 6 a n d 2 8c o u l d a l s o b e made ? a t a n d g e n e r a l l y p a r a l l e l t o r i d g ew a l l 3 6 . The o p p o s i t e e n d o f t h e a n t e n n a i s c l o s e d b yw a l l 46 a s i l l u s t r a t e d i n FIG. 4 .

T he u s e of a conventional r e c t a n g u l a r r i d g e on on ebroad w a l l t o g e t h e r w i t h a d i s s i m i l a r a r c u a t e r i d g e ont h e o p p o s i t e broad w a l l p r o v i d e s a moderate c r o s s pol a r i z a t i o n g a i n which i s u s e f u l i n t h e s y s t e m e n v i r o nment.The end o f t h e a r c u a t e r i d g e 3 8 which f o r m s a p a r t o ft h e o p e n e n d o f w a v e g u i d e a n t e n n a 2 0 e x t e n d s beyondt h e c o r r e s p o n d i n g e n d o f b r o a d w a l l 2 4 . The p r o x i m a t ee n d s o f t h e narrow s i d e w a l l s 42 and 44 a r e champhereda s i n d i c a t e d by e d g e s 4 8 shown c o n n e c t i n g t h e twob r o a d w a l l s i n FIG. 4 . The e x t e n s i o n o f a r cu a t e r i d g e 3 8b e y o n d r i d g e w a l l - 3 6 p r o v i d e s b u i l t - i n o u t s i d e - b a n dr e j e c t i o n a n d m i n i m i z e s t h e i n t e r f e r e n c e w i t h a n e a r b ya n t e n n a 5 0 ( s h o w n i n F I G . 1 ) o f h i g h e r o p e r a t i n g f r eq u e n c y .What i s c l a i m e d i s :

1 . A compact microwave a n t e n n a f o r mountingw i t h i n a r e c e s s e d f r e e s p a c e o f a m i s s i l e , c o m p r i s i n g :

a waveguide a n t e n n a h a v i n g two l o n g i t u d i n a l l y p a ra l l e l b r o a d w a l l s a n d two l o n g i t u d i n a l l y p a r a l l e l

7/27/2019 Missile Mounted Waveguide Antenna

5/5

4 , 5 7 7 , 1 9 63narrow w a l l s , whereby t h e c r o s s - s e c t i o n a l a r e a o ft h e antenna i s c o n s t a n t over t h e l e n g t h o f t h e ant e n n a and whereby t h e volume o f t h e a n t e n n a i sa d a p t e d t o ? t e n t i r e l y w i t h i n t h e f r e e s p a c e ;

on e o f s u c h broad w a l l s i n c l u d i n g a g e n e r a l l y r e c t a ng u l a r r i d g e ; a n dt h e o t h e r s a i d b r o a d w a l l be i n g a r c u a t e i n form andm o s t c l o s e l y a p p r o a c h i n g s a i d r e c t a n g u l a r r i d g e a t

t h e c e n t e r o f s u c h r i d g e , whereby a ga p i s de?nedbetween s u c h broad w a l l s and whereby t h e a r c u a t eform i s adapted t o mount with convenience on ani n t e r i o r s u r f a c e of t h e f r e e s p a c e .

4a waveguide a n t e n n a h a v i n g two l o n g i t u d i n a l l y p a ra l l e l b r o a d w a l l s a n d two l o n g i t u d i n a l l y p a r a l l e l

narrow w a l l s , whereby t h e c r o s s - s e c t i o n a l a r e a o ft h e antenna i s c o n s t a n t over t h e l e n g t h o f t h e ant e n n a and whereby t h e volume o f t h e a n t e n n a i sa d a p t e d t o ? t e n t i r e l y w i t h i n t h e f r e e s p a c e ;

on e o f such broad w a l l s i n c l u d i n g a g e n e r a l l y r e c t a ng u l a r r i d g e ; a n dt h e o t h e r s a i d b r o a d w a l l b e i n g a r c u a t e i n form andm o s t c l e a r l y a p p r o a c h i n g s a i d r e c t an g u l a r r i d g e a t

t h e c e n t e r o f s u c h r i d g e , whereby a ga p i s de?nedbetween such broad w a l l s and whe r e by t h e a r c u a t eform i s adapted t o mount with convenience on ani n t e r i o r s u r f a c e o f t h e f r e e s p a c e .

4 . The m i s s i l e o f c l a i m 3 wherein t h e f r e e s p a c e i s t h e2 . T he antenna of c l a i m 1 wherein t h e f r e e s p a c e i s t h e

m i s s i l e b o a t t a i l a n d t h e a r c u a t e form s a d a p t e d f o r f l u s hm o u n t i n g . l 53 . A m i s s i l e h a v i n g a compact r e c e s s e d mounted m i s s i l e b o a t t a i l and t h e a r c u a t e form s a d a p t e d f o r f l u s hm i c r o w a v e a n t e n n a c o m p r i s i n g : m o u n t i n g .a missile h a v i n g a recessed free space; * * * * *

2 5

3 5

4 5

5 0

5 5

6 5