Semi-Passive Backscatter Technologies for Low Cost Smart Agricultural Applications
In order to address power consumption and cost constraints in agricultural wireless sensor networks (WSNs), scatter radio technology (RFID based sensors) has attracted interest for that wireless sensing developments. We present novel, low-cost and low-power systems for sensing using backscatter sensor node/tags. The sensors can measure environmental parameters such as temperature, soil moisture and plant water stress. Next, the tags collect the information from the sensors through analog to digital converters (ADCs), and then, communicate remotely with low-cost software defined radios (SDR) or commercial receivers using bistatic backscatter architecture. Different modulation schemes have been tested thus the sensors can operate simultaneously, using frequency division multiple access (FDMA). The systems can be helpful in agricultural applications towards the prevention of water waste and towards water-use efficiency when they are connected to an irrigation system.