An Autonomous UHF RFID Transponder Concept for Fawn Saving using Solar Energy Harvesting

Abstract:
During pasture mowing in spring time several 100 thousands of wildlife animals such as fawns are killed every year by mowing machines. Conventional approaches like scaring by dogs or scarecrows are ineffective and time consuming for large areas. A microwave signal radar is also difficult to apply in agriculture, because the finding and rescuing processes take place at the same time. The present publication describes an innovative concept in which these two processes are separated. For this purpose the fawns, covered in high and thick grass, are marked with an autonomous RFID transponder to recover them during the mowing sequence. This specific situation leads to particular technical requirements. In this low light environment silicon based solar cells decrease in efficiency whereas dye-sensitized and organic solar cells increase. The transponder is battery less energy supplied and integrated in the earmark of the fawn. A low power system architecture and an efficient power management allow a long communication range with an adaptive sending interval in low energy and light conditions while ensuring localization by the mowing machine.