Antennas for Nonsinusoidal Electromagnetic Waves

Abstract

The e f f i c i e n t r a d i a t i o n o f s i n u s o i d a l waves i s a ccom p lish ed by means o f antennas t h a t r e s o n a t e w ith th e wave t o be r a d i a t e d . S im i la r r e so n a n t an ten n as f o r Walsh waves h a v e been d e s c r ib e d , but t h e y r e q u ir e t im e v a r i a b l e e le m e n ts i n t h e form o f s w i t c h e s t h a t made them im p r a c t i c a l . The c u r r e n t ly u se d a n ten n a s f o r th e r a d i a t i o n o f Walsh wa­ v e s r e q u ir e t h e d i s s i p a t i o n o f most o f th e power i n r e s i s t o r s i n ord er t o a v o id r in g in g and th e r e s u l t i n g d i s t o r t i o n s o f th e r a d ia t e d w aves . A new ty p e o f antenna t h a t a v o id s t h i s d i s s i p a t i o n o f power makes u se o f h y b r id cou­ p l e r s and d e la y feed b a ck l i n e s t o o b t a in r a ­ d i a t o r s t h a t are i n re so n a n ce w ith any wave o f a c e r t a i n p e r io d , r e g a r d l e s s o f th e t im e v a r i a t i o n d u r in g t h i s p e r io d . No t im e v a r i a ­ b l e e le m e n ts are n eed ed . The e f f i c i e n c y o f t h e s e a n ten n as shou ld equal t h a t o f r e so n a n t d i p o l e s f o r s i n u s o i d a l w aves .