Chapter 14 391
Real Time TDMA Formats
Enhanced Observed Time Difference (E-OTD)
Figure 14-2 Multiframe Hierarchy
Broadcast Channel (BCH)
In a broadcast channel a 51-frame multiframe is transmitted on time slot zero and provides the mobile
station with system information which the mobile station needs to gain access to the network. The broadcast
channel needs to remain at a constant power so other mobile stations can distinguish the broadcast channels
from normal channels. Therefore all eight time slots need to be used during each TDMA frame.