Monitoring the environment by enhancing the capabilities of a fleet tracking system

Our approach aims to enlarge the application domain of a GPS-based tracker. We have configured the device using its configuration software, allowing us to organize multiple options for data acquisition and corresponding transfer between the device and the server. The first option was for SMS mode, mostly used in areas without GPRS (minimum 2.5 G) coverage or in situation of high price rates for GPRS usage. The second one allows the GPRS mode. There were developed two proceedings for using the fleet tracker in environmental surveillance. One possibility was based on 1-Wire® (Dallas Maxim) data protocol, that might provide information about some environmental parameters like temperature, relative humidity or even pressure. The other opening was underlain on the tracer's capability of processing analogue voltages. In consequence, we have enlarged the category of surveyed environmental parameters by using a calibrated magnetic field sensor (with well known calibration graph), in order to transmit the values of the background magnetic field. The preliminary tests were done just for transmitting the d.c. values delivered by a true rms converter that processed the voltage provided by the sensor, after previous integration.