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Many r a d a r and communication a p p l i c a t i o n s r e q u i r e phased a r r a y elements h a v i n g dual p o l a r i z a t i o n . Where t h e r e i s a requirement f o r low p r o f i l e and/or c o n f o r m a l i t y , t h e m i c r o s t r i p patch radiat o r becomes a prime candidate. Described h e r e i n i s a well-matched m i c r o s t r i p patch r a d i a t o r havi n g orthogonal d u a l -l i n e a r p o l a r i z a t i o n . T h i s i s accomplished over a wide bandwidth and wide scan angle under a l o w -p r o f i l e c o n s t r a i n t . VSWR o v e r a 10% bandwidth and suppression o f cross p o l a r i z a t i o n by more than 20 dB. u r a t i o n are as f o l l o w s ; orthogonal balanced probe feeds, one p a i r connected t o t h e base p l a t e ( h o r i z o n t a l p o l a r i z a t i o n ) and t h e o t h e r connected t o t h e patch ( v e r t i c a l p o l a r i z a t i o n ) , as shown i n Fig. 1; a m i c r o s t r i p matching c i r c u i t , as represented by t h e schematic i n Fig. 2; and t h e topology which permits both p o l a r i z a t i o n matching c i r c u i t s t o c o -e x i s t i n one s t r u c t u r e . Both l i n e a r p o l a r i z a t i o n implementations were determined by a r i g o r o u s numerical computer code [4], [3] and employ a doubletuned broadband-matching technique [2]. The design was v e r if i e d u s i n g an i n f i n i t e -a r r a y waveguide s i m u l a t o r [l] and t h e performance evaluated by s m a l l l a r r a y mutual c o u p l i n g and patt e r n measurements. Computer-aided design.techniques have been a p p l i e d t o t h e l a y o u t , photo exposure, e t c h i n g and d r i l l i n g o f t h e m i c r o s t r i p -p a t c h p r i n t e d -c i r c u i t matching networks. The d u a l -p o l a r i z e d patch r a d i a t o r c o n s i s t s o f a conducting patch over t h r e e l a y e r s o f d i e l e c t r i c (E,. = 2.2) and a p a i r o f balanced probe feeds. t y p e connector and a 50 ohm m i c r o s t r i p l i n e i n t o a r e a c t i v e s p l i t t e r . An o p e n -c i r c u i t e d stub i s used t o double-tune t h e patch resonant c i r c u i t response. The r a d i a t o r c o n s i s t s o f a < 0.10 wavelength t h i c k d i e l e c t r i c l a y e r sandwiched between two t h i n d i e l e c t r i c layers. The patch i s etched on t h e t o p s i d e o f t h e t h i n t o p l a y e r ; t h e h o r i z o n t a l p o l a r i z a t i o n balun i s etched on t h e bottom s i d e o f t h i s l a y e r . The v e r t i c a l p o l a r i z a t i o n balun i s etched on t h e bottom s i d e o f t h e t h i c k l a y e r separated from t h e ground p l a t e by t h e o t h e r t h i n l a y e r . The patch i s used as t h e ground plane f o r t h e h o r iz o n t a l p o l a r i z a t i o n balun and t h e bottom p l a t e t h e r e t u r n f o r t h e v e r t i c a l p o l a r i z a t i o n balun. The probes f o r t h e h o r i z o n t a l p o l a r i z a t i o n are i s o l a t e d from t h e patch u s i n g a p l a t...