Remote monitoring of wildlife and environment via gps/gprs

Abstract

This paper proposes a novel and economic solution to wildlife monitoring in places with GSM network coverage. The work arises from a project to monitor the nesting environment and breeding behavior of the Oriental Pied Hornbill which was thought to be extinct in Singapore as it had not been seen for more than 150 years but was rediscovered in 1994. With a potentially large number of hornbills to be monitored, economic solutions for monitoring are demanded. The popular satellite-based Argos System is not practical not only because it is expensive, but also because the accuracy is inadequate. The proposed system is an integration of a specially designed GPS tracker and a GPRS Data Server. In the GPS tracker, an ultra low power microcontroller manages five other modules including a GPS receiver, a GSM/GPRS module, an accelerometer, a MicroSD card and a battery level gauge. The main challenge in the design of the GPS tracker is to optimize the standby time so that it can work continuously without charging for months. Power saving is achieved not only by selecting low power modules but also by implementing duty cycle scheduling to allow as many modules as possible to sleep or even power off. The novelty of the GPS tracker is that after the GPS receiver captures enough GPS signal data, it enters standby mode immediately without computing the position fix. The digitized GPS signal data is written to a MicroSD card. GPS data is uploaded to the GPRS Data Server via GPRS network. Position fixes are post-processed in the server computer. An accelerometer is also integrated not only to obtain movement data but also to aid decision making in filtering outliers and adjusting deviated coordinates in the post-processing steps. Besides, the tracker also has a battery level gauge which measures the battery level so that users will be notified by SMS when the battery level is low. Users can also configure settings via SMS and settings will take effect right after GSM module's next scheduled wakeup.