GPS Module

Overview

The telematic device uses a GPS receiver module to calculate the position of the device, and, in turn, the vehicle's position. This position data is then sent to the central server to allow the customer to track their goods. The central server will then use this data to report on the local weather and road conditions.

The GPS module that has been chosen for the telematic device is Motorola's M12 oncore module. This device was designed with low-power consumption in mind. The standard data link on the device is a TTL compatible serial channel allowing two different message protocols; the standard National Marine Electronics Association (NMEA) protocol, or Motorola's binary protocol.

GPS module specification

 
Power supply: 2.75 - 3.2 Vdc
Receiver: 12 parallel channels
Acquisition time: <15 s when hot
  <60 s when cold
Position accuracy: 100 m
Output messages: Latitude, longitude, height, velocity, heading and time
Output format: Motorola binary protocol @ 9600 baud
  NMEA 0183 @ 4800 baud

 

Level 1 data-flow diagram showing the data-flow between the telematic device and GPS module