Specifications

GLOBAL POSITIONING SYSTEM RECEIVER
Portable Radio Modem 660
R4-11-4G Equipment Descriptions 4-41
4.5 Global Positioning System Receiver
The GPS receiver can be connected to the AUX port of a VRM-500 or VRM
650 modem that includes the GPS interface option (Z167), as part of a legacy
AVL solution only. Concurrent Private DataTAC 2.0 value-added services are
not supported by the modem or any device connected to the DTE port of the
same modem. Any connected DTE is limited to communicate only with the
same FLM host or message switch as the GPS receiver, and cannot enable IP,
data compression, or security services.
Alternatively, the GPS receiver can be connected to the comm port of an MW-
520 (the MW-520 has an available internal GPS receiver option) or a second
comm port of notebook computer (the other port being connected to a VRM).
In the first configuration, the VRMs and Private DataTAC network serve as a
communications pipe between the AVL application running in the host
computer and the GPS receivers in the vehicles. This bi-directional
communications between the host and the GPS receiver support a broad
range of AVL and fleet management solutions. Customers can program the
receiver to report autonomously at regular intervals or on demand by the
host. The host can use the mobile network to dynamically control the mobile
unit’s reporting location report content.
The VRM provides a controller function that initializes the GPS receiver at
start-up to a specific configuration. This default is stored in the VRM’s non-
volatile memory. The VRMs do not require separate intelligent controllers or
DTE applications.
The VRM message arbitration and queuing supports concurrent operation
with a computer device connected to the DTE. This application
independence allows the user to maintain the vehicle tracking function even
when the DTE is disconnected.
L3073 • PLACER 450 SENSOR ANTENNA BUNDLE
The L3073 is a Trimble® Placer™ 450 GPS receiver and antenna bundle,
which includes the GPS receiver, power cable, a mini bulkhead antenna, a
5mm cable to connect the receiver and antenna, and an antenna mount
gasket. The Placer 450 GPS sensor is an eight-channel receiver with two I/O
ports that can be connected to modems and radios. Each receiver provides
two input and two output lines.