P/N 1389990 Rev B (ECN 32099)
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Spread Spectrum Installation Guide
passing through a repeater). The Base RTU then sends the information to the Bridge
which in turn sends it to the web portal via the Internet. Data and commands issued
from the web portal are sent to the Bridge which then sends them to the Base RTU for
transmission. The transmitted command is then picked up by the Pivot that it was
addressed to (possibly after passing through a repeater).
3.1 FieldNET RTU
The FieldNET RTU is a radio module installed on the center pivot. It
transmits data to and receives data from the Base RTU connected to the
Bridge. The FieldNET Pivot RTU is connected directly to FieldBOSS and
VISION modules. Panels that are not FieldBOSS or FieldVISION require a
Basic Link and a FieldNET RTU.
The Pivot RTU is configured with internal switches. The switches are used
to configure the RTU for pivot operation or as a Base (a RTU connected to the Bridge).
The switches are also used to select the hop pattern that the RTU operates on.
FieldNET RTUs are near line of site (NLOS) transceivers, which mean that direct line of
site is not required but the antenna the RTU is communicating with cannot be
completely obscured. With good line of sight the range of the RTU is approximately 10
miles. Each site must be evaluated to determine the range of the RTUs. Each
installation site will have one FieldNET Pivot RTU or FieldNET PRO per pivot to be
controlled.
3.2 Repeater
Repeaters are used to extend the range of the wireless network. Each
Repeater includes two radios, each with its own hop pattern and antenna.
The hop pattern for each radio module is selected by setting internal
switches. There is one bank of switches for each of the two radio modules.
Data that is received on the hop pattern for one antenna is then transmitted
on the hop pattern for the other. Multiple RTUs can be linked to a single
repeater. Several repeaters can be daisy chained to extend the range of the
wireless network even farther. Repeaters range is maximized by mounting it as high as
possible. The Repeater is shipped with a 12 VDC power supply that requires 120 VAC
for power. The Repeaters are near line of site (NLOS) transceivers.
3.3 Bridge
A Bridge is a standalone computer that provides the
connection between the FieldNET RTUs and the Internet. A
FieldNET RTU, referred to as a Base, is connected to the
