Spread Spectrum Interference to Voice Communications Systems

A computer s im u la t io n model d eve lop ed f o r d e t e r ­ mining th e manner in which u n d e s ire d spread spectrum s i g n a l s a f f e c t th e perform ance o f c o n v e n t io n a l narrow­ band AM and FM v o i c e communications system s i s o u t ­ l in e d . D ir e c t s e q u e n c e , freq uency-hopp in g and h y b rid , fr e q u e n c y -h o p p in g /d ir e c t s e q u e n c e , spread spectrum in t e r f e r e n c e s i g n a l s were modeled. Using a r t i c u l a t i o n index as th e measure o f perform ance, com parisons are made between system performance f o r d ir e c t s e q u e n c e i n t e r f e r e n c e and w h ite Gaussian n o i s e . System p e r ­ formance f o r freq uency-hopp in g o r fr eq u en cy -h o p p in g / d ir e c t s e q u e n c e in t e r f e r e n c e i s compared w ith th a t fo r p u lsed in t e r f e r e n c e .