=== Time Division Multiple Access ===
In this system, each user is allocated a different time slot. Forward link frequency and reverse link frequency is the same. A synchronous switch is responsible for the time switching.
[[Image:cdma10.jpg|thumb|600px|center|TDMA]]
=== Code Division Multiple Access ===
There is no restriction on time and frequency in this scheme. All the users can transmit at all times and at all frequencies. Because users are isolated by code, they can share the same carrier frequency, eliminating the frequency reuse problem encountered in other technologies.