Specifications

Introduction
August 08, 2000 68P81095E55-E 1-1
Chapter 1
Introduction
This chapter provides an introduction to the iDEN
®
system communications types, a
model to iDEN system, and a discussion of changes to the system that have taken
place since the last release of this document.
System Overview
The outgrowth of the wireless communications market has produced vast
opportunities to enhance and improve the communications between individuals.
Because of this growth the need to optimize Radio Frequency (RF) spectral
resources and provide ever-increasing services is essential.
To support the increase in wireless services while making best use of available
resources, the iDEN system capitalizes on the fact that communications can be:
• Half-duplex — where one user is transmitting (talking) and other users are
receiving (listening)
• Full-duplex — where there is an open bi-directional link that allows full two-
way communication
Many times communication does not require a full-duplex link. Messaging, paging,
some forms of data communication and structured voice communication are, or can
effectively operate in, half-duplex mode (Chapter 4, Dispatch Call Processing).
Traditional telephone conversations and more intensive data links require the ability
to interrupt; that requires full-duplex operation (Chapter 5, Interconnect Call
Processing).
The iDEN system provides both full and half-duplex operations. This melding of
communications methods allows much of the voice traffic to be run in half-duplex
mode, while providing full-duplex functionality when required.
As part of the ongoing effort to support the outgrowth in wireless communication,
the iDEN system is an integration of traditional Push-To-Talk (PTT), half-duplex,
analog radio technology and feature-rich, full-duplex digital cellular
communications. This integration of mobile communication technologies provides
state-of-the-art functions and benefits to mobile users while optimizing the available
infrastructure resources.