CDMA (Code division multiple access) Interview Question:

Please differentiate between CDMA and TDMA?

Submitted by: Administrator

CDMA

Power limited system
While people talking, random noise band playing occurs
Conversation need to be extracted from the background din
GP is high when people speak different languages, which is easier to distinguish individual speakers
It is difficult for distinguishing individuals, when GP is low.
The system performance will be degraded for every user when the number of users increases.
Fading would be reduced with wide frequency spectrum
Need to have separate multipath signals with different delays by “chip” unit.

TDMA

Receiving or transmission is allowed for only one user in a given slot
All slots are assigned cyclically
The transmission is non-continuous
It is essential to use digital data and modulation
Data rate overhead is between 20% - 30%
Overhead tradeoffs are size of data payload and latency
Multiple users are shared with single carrier frequency
Handoff is made simpler by using non-continuous transmission
All slots are assigned on demand
Due to reduced inter user interference, the power control is less stringent
Submitted by: Administrator