Campbell Scientific 9522B Iridium Satellite Modem and COM9522B Interface Modem - Manual (Page 9)

9522B Iridium Satellite Modem and
COM9522B Interface Modem
1. Overview
1.1 General Description and Modes of Operation
The Iridium satellite network consists of a constellation of 66 satellites situated
in six planes in low-earth orbit. Each plane is populated by 11 satellites in
polar orbits, giving the Iridium network excellent coverage in high latitudes
that equatorial satellites often cannot reach.
Iridium provides five different services: dial-up data, Short Burst Data (SBD),
Short Messaging Service (SMS), Internet Connection, and Router Based
Unrestricted Digital Internetworking Connectivity Solution (RUDICS). For
the purposes of this manual, we will discuss dial-up data and RUDICS as the
preferred methods of connecting with Campbell Scientific dataloggers.
However, while other services may not be directly relevant to datalogger
operations, the end user may find them valuable. Please contact your Iridium
service provider with questions on these methods.
1.2 Modem Models and Accessories
The Iridium satellite system used by Campbell Scientific consists of the 9522B
modem, COM9522B interface module kit, data cables, antenna and power
supply. The base and remote stations use the same modem type, which both
require a change to their configuration.
When possible, the recommended connection of the remote modem to a
datalogger is via the RS-232 port. It is possible to communicate with a
datalogger via either the CS I/O port or COM Ports 1–4. All datalogger
connections require appropriate cabling and interface accessories (see TABLE
1-1).
The COM9522B is required to connect the modem to the datalogger or
computer and an appropriate power source. For remote applications where AC
power is not available, it is recommended to operate the modem on a schedule
to avoid discharging the battery power supply.
The antenna used for both Iridium modems is the Iridium fixed mast antenna,
pn 30741 (also known as AT1621-142). For best signal reception, the antenna
should be mounted so that it has an unobstructed view of the sky and the
horizon. Reception quality changes as satellites move overhead; therefore, it is
critical that the view be clear. See Section 7, Troubleshooting Tools and Tips,
for information about checking signal quality.
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