A MCM-based microsystem for soil moisture measurements

Abstract

This work presents a Multi-Chip-Module (MCM) based microsystem for irrigation control in agriculture. The proposed microsystem includes a soil moisture microsensor, an analog-to-digital converter, signal processing circuits (digital filtering and sensor interface) and a RF 433MHz transmitter. A heat--pulse technique is used to determine the volumetric heat capacity and hence the water content of a porous media, such as the soil. This method is based on the Joule effect (heater probe) and in Seebeck effect (temperature probe). By using CMOS standard processes (low-cost) a network could be implemented in order to achieve an accurate measurement of the soil moisture at the plant root level.