User's Manual

Draft

RT System 2 v2.0.0 23 Deployment Guide R00.e

3. Backhaul

3.1 Overview

In network communications, the backhaul is the part of the network that

contains the links and equipment between the core network and the sub

networks.

Wireless mesh networking is a method where each radio node in the network

captures and disseminates its own data as well as serves as a relay for other

radio nodes in the network sending data along a path, hopping from one node

to the next.

Power over Ethernet (PoE) is a technology that passes electrical power along

an Ethernet cable. PoE is used where DC power is not available and USB

unsuitable. Power can be supplied at the end of a network span or somewhere

in the middle.

PoE switches supply power at the end of a span. The RT System 2 Line

Interface Unit acts as a switch with PoE.

PoE injectors supply power somewhere between the PoE switch and the

powered device. They inject power and do not affect the data. A discrete PoE

injector is used when configuring the Fluidmesh radios.

The RT System 2 Central Recording System is a fully connected mesh network

of Wireless Remote Units (WRUs) that communicate in a relay pattern (bucket-

brigade or string-of-pearls) with a Line Interface Unit (LIU) on the 2.4 GHz

Industrial, Scientific, and Medical (ISM) radio band.

The LIU is composed of the following discrete components:

 Line Interface Unit (LIU) box

 12 V DC, 5 A capable Battery or Power Supply

 Cables

 Mast, mast base, and guy-wires

 5.8 GHz backhaul radios

 Antennas

The LIU communicates with the Central Software System (CSS) computer in

the central recording truck along a backhaul on the 900 MHz or 5.8 GHz ISM

radio band. Some smaller systems may not require a backhaul.

The Central Software System (CSS) communicates with the field units via the

backhaul radios. The backhaul radios act as access points for the LIUs.

The following figure illustrates the possible LIU components: