Describe codes in CDMA?
Kuan-yin 05-November-2007 04:29:24 PM

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CDMA uses unique spreading codes to spread the baseband data before transmission. ... CDMA codes are not required to provide call security
Posted by waqasahmad


The spread spectrum encoding system used by Is-95 CDMA systems use orthogonal codes,also called as Walsh code (WC).Original coding is a system of spreding codes that have no relationship to each other. The system also combines these orthogonal codes with two pseudorandom noise(PN) sequences for eang communication channel. There are different codes used for different types of channels. The overhead channels(control channels) have designated codes to be used while traffic channels codes are selected at the time the transmission or when a call is originated.
Posted by karthi



Posted: 05-November-2007 09:02:14 PM By: karthi

The spread spectrum encoding system used by Is-95 CDMA systems use orthogonal codes,also called as Walsh code (WC).Original coding is a system of spreding codes that have no relationship to each other. The system also combines these orthogonal codes with two pseudorandom noise(PN) sequences for eang communication channel. There are different codes used for different types of channels. The overhead channels(control channels) have designated codes to be used while traffic channels codes are selected at the time the transmission or when a call is originated.

Posted: 28-February-2009 12:38:37 PM By: waqasahmad

CDMA uses unique spreading codes to spread the baseband data before transmission. ... CDMA codes are not required to provide call security