Setting The Center Frequency - Wi-LAN AWE120-58 Ultima3 Series User Manual

Configuration

Setting the Center Frequency

A center frequency defines the RF channel that a unit uses to transmit and receive. The AWE 120-58 can
operate at a center frequency ranging from 5.7410 GHz to 5.8338 GHz, in 400 kHz steps. All units in the
same system must be set to the same center frequency.
If you plan to co-locate AWE 120-58 systems, you will need to use more than one center frequency.You will
choose center frequencies that are well-separated from each other. The following section
Frequencies explains how to choose center frequencies.
Choosing Center Frequencies
A simplified diagram of the spectrum around a center frequency (when transmitting) is shown below.
Center Frequency Spectrum
5.7410 GHz
Only the 33 MHz data region of the 66 MHz spectrum contains data; the remaining 16 MHz side lobes
contain no useful information (frequency ranges given are approximate).The side lobes operate at a much
lower power than the data region.
If only one center frequency is required, simply choose a frequency between 5.7410 GHz and 5.8338 GHz (in
400 kHz increments). You will probably choose a center frequency where the 5.8 GHz ISM band is cleanest,
meaning a frequency where no other people are transmitting.
If two or more AWE 120-58 systems must be co-located, center frequencies are selected that have as much
separation as possible so different systems do not interfere with each other. It is very important that the 33
MHz data regions of adjacent systems do not overlap. System performance is also better if the side lobes of
one system do not overlap the data region of another system. It does not matter if the side-lobes of two
systems overlap.
98
66 MHz
16 MHz 33 MHz
Data
Region
Side
Lobe
Center Frequency
16 MHz
Side
Lobe
AWE 120-58 Ultima3 Series User Guide
Choosing Center
5.8338 GHz