About GSM and CDMa, there was alread a thread, just searched for it...and got it!
http://www.thinkdigit.com/forum/viewtopic.php?t=12683
Anyway i was post what i posted there...
This all depends on multiplexing issues.
Three types:
Time division multiplexing
frequency division multiplexing
wave division multiplexing
TIme division is actually now divided into TIME divsion multiple access(TDMA) and FREQUENCY divsion multiple access(FDMA).
Now TDMA is divided into CDMA (code division multiple access). WCDMA is WIDE CODE divition multiple access. More BW is accomodated with wider range of freq of operation.
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GSM and CDMA
It is just a different tech being used. I can try and explain with a help of example.
Consider a 10 subscribers who want to get connected with other person. (either same network or different)
CDMA: All the ten subscribers are placed in a single room, and their voice signal is encrypted, so that it isnt decrypted by unauthorised persons or the wrong subscriber. The decryption is done the person who actually receives the call.
GSM:The ten subscribers are placed in defferent rooms and only the person who calls and the person who receives the call will be in that particular room. Privacy issues are less here.
Remember the call intrution in case of reliance phone early on when they launched?
CDMA actually oofers a comparitely cheaper network access. A
nd also the voice clarity will be marginal better (the signal is decryped and amplified so the clarity will be bound to be good).
Please tell me!!
Linear Mode
