User's Manual

U-NII Config & User Guide 5.2 Axxcelera Broadband Wireless
13 RF Design and Planning
13.1
Overview
The AB-Access system is a communications system using wireless technology in the U-
NII & ISM frequency bands. Therefore understanding Radio Frequency (RF) system design is
necessary to ensure gook link quality and, thus, good system performance. This section discusses
the basics of RF Design and Planning from the perspective of deploying the AB-Access System.
13.2 The U-NII & ISM Channel Plan
In 1997 the FCC amended its Part 15 rules to make 300 MHz of spectrum available for
high-speed wireless digital communications with unlicensed operation. This band, called the
Unlicensed National Information Infrastructure or U-NII band, provides the spectrum at 5.15 to
5.25 GHz for indoor use, and 5.25 to 5.35 and 5.725 to 5.825 GHz for outdoor use. The peak
output power permitted is limited to 23 dBm EIRP in the lower (indoor) band, 30 dBm in the
mid-band, and 36 dBm in the upper band.
The 5.8 GHz ISM (Industrial Scientific and Medical) band ranges from 5.725-5.850 GHz.
Which is an unlicensed frequency limited to 36 dBm for PTMP equipment. The limit for PTP is
higher than PTMP.
NOTE: AB-Access uses both the U-NII and ISM band for its upper band channels.
NOTE: BPSK modulation is only approved by the FCC for the upper band
channels.
13.3 Air Interface
The SU talks to the AP over a proprietary airlink protocol on a single 15 MHz channel
using QPSK or BPSK modulation and a technique called Time Division Duplex (TDD). Both
upstream and downstream traffic time-share this channel.
13.4 Wireless MAC
March 10, 2003 Company Confidential Page 128 of 149