Agricultural sector is backbone of Indian economy. As population growth results in an increasing demand on water supply. Usually, growers determine how much water is needed to irrigate their field based on the amount of time elapsed since last irrigation cycle. An automated irrigation system enables the users to constantly monitor the relative soil moisture at many different locations throughout the field to more precisely schedule irrigation cycles. The sensing system is based on a feedback control mechanism with a centralized control unit which regulates the flow of water on to the field in the real time based on the instantaneous temperature and moisture values. Depending on the varied requirement of different crops, a lookup table has been prepared and referred to for ascertaining the amount of water needed by that crop.

1. Aman Tyagi1, Arrabothu Apoorv Reddy2, Jasmeet Singh3, Shubhajit Roy Chowdhury4. "A Low cost Portable Temperature-Moisture Sensing Unit With Arti_cialNeural Network Based Signal Conditioning for Smart Irrigation Application", International Journal on Smart Sensing and Intelligent Systems Vol. 4, NO. 1, March 2011
2. Juan F. Posada, Member, IEEE, Juin J. Liou, Member, IEEE, and Richard N. Miller, Member, IEEE "An Automated Data Acquisition System for Modelling the Characteristics of a Soil Moisture Sensor" IEEE Transaction on Instrumentation and Measurement, Vol. 40. No. 5, October 1991
3. Cuihong Liu, Wentao Ren*, Benhua Zhang, Changyi Lv "The application of soil temperature measurement by LM35 temperature sensors" International Conference on Electronic & Mechanical Engineering and Information Technology 12-14 August 2011.
4. Baoping Feng, Zhirong Wang, Jianfeng Zhang, Wenyan Wang. "Theory and experiment on temperature effect in soil," Northwest Water Resources & Water Engineering, 12(4), 2001, pp. 6-11.
5. Xiaojun Qiao, Xiuhong He, Xiaohong Du, Hongwu Tian, Cheng Wang. "Design and Implement of Multi-Point Soil Temperature Measurement," Journal of Shenyang Agricultural University, 37(3), 2006, pp. 278-281.
6. Yuxiao Song, Jian Wang, Xiaojun Qiao, Wengang Zheng, Xin Zhang. "Development of Muti-functional Soil Temperature Measuring Instrument," Journal of Agricultural Mechanization Research, (9), 2010, pp. 80-84.
7. Ronald M. Benrey, 'This sprinkler-control system thinks for itself', Popular Science, April 1968, P - 182.
8. I. F. Akyildig. A Survey on Sensor Networks [J]. IEEE Communications Magazine,2002, 8:725-734. 2005.
9. 'P89v51 RD2', Datasheet Rev. 01- 01 March 2004, Philips Corporation.
10. Mahir Dursun* and Semih Ozden"A wireless application of drip irrigation automation supported by soil moisture Sensors", Scientific Research and Essays Vol. 6(7), pp. 1573-1582, 4 April, 2011 .
11. 'LM-35 Precision centigrade temperature sensors', Datasheet No. DS005516, National Semiconductor Corporation, 2000.
12. T. Seiyama, N. Yamazoe, H. Arai, 'Ceramic Humidity Sensors', IEEE Transactions on Components Hybrids, and Manufacturing Technology', Jun 1980, Volume: 3 Issue:2, pp. 85-96 .
13. ZigBee Alliance. ZigBee specification: ZigBee document 053474r06, Version 1. 0[S]. 2004.
14. A. Cano and E. L´opez-BaezaJ. L. A˜n´on and C. Reig C. Mill´an-Scheiding," Wireless Sensor Network for Soil Moisture Applications", International Conference on Sensor Technologies and Applications 2007.

Moisture Sensing Temperature Sensing Microcontroller Wsn.