OPW M00-20-7074, Руководство пользователя

Страница: 8 / 43

2.1 Pre-Installation
This section provides information about Wireless Petro-Net Modem requirements and restrictions for proper
installation.
2.1.1 Installation Restrictions and Requirements
NOTE:
l
Some sites might NOT be suitable for Wireless Communication.
l
Avoid metal buildings; the wireless modem will not communicate through metal
buildings.
l
Locate the modem near a window.
l
Mount the antenna on the outside of the building.
l
Keep the path to the receiving modem clear. If vehicle traffic at the island blocks the
view of the receiving modem, you must reposition the antenna to maintain LINE-OF-
SIGHT from antenna to antenna.
IMPORTANT:
Improper operation due to poor installation planning is not covered under
warranty; it is your responsibility to verify the suitability of the wireless application.
2.1.2 Conduct a Site Survey
Before you decide to install the Wireless Modem, you must first make sure that it will work at the desired
location. Communication systems have several components that should be looked at in each system:
l
Transmitting element
l
Receiving device
l
The environment through which communication is occurring; and
l
Antennas or other focusing elements
Environment
The space between the transmitter and the receiver is the system’s environment. This will be the main focus
of your site survey. Physical obstructions and noise (interference) can enter into the environment and limit the
system’s ability to get information from one place to another.
Attaining RF Line-of-Sight (LOS) between the sending and receiving antennas is essential in achieving a
reliable signal between the FIT and the FSC. There are two types of LOS that are generally used to describe
an environment:
l
Visual LOS is the ability to see from one site to the other. It requires only a straight linear path between
two points.
l
RF LOS requires not only visual LOS, but also a football-shaped path, called a Fresnel Zone, free of
obstacles for data to optimally travel from one point to another.
Doc. No.: M00-20-7074 Rev.: 6
Page 8 of 43