User's Manual Chapter 13

Chapter 7: Operational Description
AT&T Wireless Services
7-91
FCC Type Acceptance Application
10991 Rev. 1.0 7/6/99
Figure 7.6— HSD Logical Channel Relationships
7.2 Airlnk Overview
The AT&T Fixed Wireless Services PWAN utilizes a proprietary airlink
technology to maximize the efficient use of spectrum while providing a
secure wireless interface to the WRDT. This chapter provides an
overview of the airlink design as well as functional descriptions of the
control and traffic channels.
7.2.1 PWAN Physical Layer Overview
The PWAN physical layer is based on an Open Systems Interconnect
(OSI) layer model. Figure 7.7— depicts the application of the OSI
model to the PWAN airlink protocol stack.
Base
Downlink
Uplink
RU
Channel Stream
(2 x 72 kbps typical)
(1 x 72 kbps typical)
RU RU