Institutionen för systemteknik Department of Electrical Engineering (ISY) Examensarbete Design of Autonomous Low Power Sensor for Soil Moisture Measurement Master thesis performed at Electronics Systems of ISY in Linköping University by Zubair Ahmed LiTH-ISY-EX--12/4639--SE Linköping 2012 Department of Electrical Linköpings tekniska högskola Engineering Linköping University Institutionen för systemteknik SE-581 83 Linköping, Sweden SE-581 83 Linköping 1 Design of Autonomous Low Power Sensor for Soil Moisture Measurement Master thesis performed at Electronics Systems of Linköping Institute of Technology by Zubair Ahmed LiTH-ISY-EX--12/4639--SE Supervisor: Peter Johansson Examiner: Dr. J Jacob Wikner November 11th, 2012 2 TABLE OF CONTENTS Chapter 1 introduction......................................................................................................................................................................................................................15 1.1 Introduction..........................................................................................................................................................................................15 1.2 Problem Description............................................................................................................................................................................15 1.3 Project Background.............................................................................................................................................................................15 1.4 Structure of the Report........................................................................................................................................................................16 1.5 Results.................................................................................................................................................................................................16 Chapter 2 Literature Review............................................................................................................................................................................................................17 2.1 Introduction..........................................................................................................................................................................................17 2.2 What is droughts.................................................................................................................................................................................17 2.2.1 Impact of droughts.......................................................................................................................................................................17 2.2.2 Droughts Types............................................................................................................................................................................20 2.2.2.1 Meteorological Drought .......................................................................................................................................................20 2.2.2.2 Agricultural Drought .............................................................................................................................................................20 2.2.2.3 Hydrological Drought ...........................................................................................................................................................20 2.2.2.4 Socioeconomic Drought ......................................................................................................................................................20 2.3 Sensor and Sensing............................................................................................................................................................................21 2.4 Classifications and Examples of Sensors...........................................................................................................................................22 2.5 How Sensor Works..............................................................................................................................................................................22 2.6 Sensor Node Architecture ..................................................................................................................................................................23 2.7 Communication Interfaces..................................................................................................................................................................24 2.7.1 I2C (Inter-Integrated Circuit)........................................................................................................................................................24 2.7.2 SPI (Serial Peripheral Interface)..................................................................................................................................................26 2.7.3 USB (Universal serial Bus) .......................................................................................................................................................26 2.8 Wireless Sensor Network....................................................................................................................................................................27 2.8.1 Sensor Network Protocols...........................................................................................................................................................27 2.8.1.1 The architecture of Protocol Stack ......................................................................................................................................28 2.8.2 IEEE 802.15 Standard Family.....................................................................................................................................................28 2.8.3 IEEE 802.15.4 protocols..............................................................................................................................................................30 2.8.4 Data Centric protocols.................................................................................................................................................................30 2.8.5 Wireless Sensor Network Topologies..........................................................................................................................................34 2.9 ZigBee.................................................................................................................................................................................................34 2.10 6LoWPAN..........................................................................................................................................................................................35 2.11 ONE NET...........................................................................................................................................................................................35 2.12 DASH7...............................................................................................................................................................................................36 2.13 IEEE 1902.1 (RuBee)........................................................................................................................................................................36 2.14 Soil Moisture Measurements Techniques.........................................................................................................................................36 2.14.1 Dielectric Constant Soil Moisture Probes..................................................................................................................................36 2.14.2 Resistive Soil Moisture Sensor..................................................................................................................................................38 2.15 Currently Available Low Power Sensors for Soil Moisture................................................................................................................40 2.15.1 VH400 Series Soil Moisture Sensor..........................................................................................................................................40 2.15.2 EC-5 Soil Moisture Sensor........................................................................................................................................................41 2.15.3 Arduino Compatible Soil Moisture Sensor.................................................................................................................................42 2.16 Conclusions.......................................................................................................................................................................................43 Chapter 3 Implementation of Low Power Sensor Network.........................................................................................................................................................45 3.1 Introduction..........................................................................................................................................................................................45 3.2 Previous system..................................................................................................................................................................................45