Codan Radio P25 Training Guide - Manual (Page 95)

P25 RADIO SYSTEMS | TRAINING GUIDE
Chapter 7: P25 Phase 2 Page 87
Time Division Multiple Access (TDMA)
Time Division Multiple Access is a process of sharing a single radio channel by dividing the channel
into time slots that are shared between simultaneous users of the radio channel. When a mobile radio
communicates with a TDMA system, it is assigned a specifi c time position on the radio channel. TDMA
systems allow several users to use different time positions (time slots) on a single radio channel,
increasing their ability to serve multiple users with a limited number of radio channels. Figure 7-2 shows
how a single carrier channel is time-sliced into two communication channels. Transceiver number 1 is
communicating on time slot number 1 and transceiver number 2 is communicating on time slot number
2. This is considered a two-slot TDMA system within 12.5 KHz.
Figure 7-2: Time Division Multiple Access
Channel 2
Frequency 1
(12.5 KHz)
Channel 1 Channel 2
time
Channel 1
Channel 1 Channel 2