ISSN(Online): 2320-9801 ISSN (Print): 2320-9798 International Journal of Innovative Research in Computer and Communication Engineering (An ISO 3297: 2007 Certified Organization) Vol. 2, I ssue 5, May 2014 Copyright to IJIRCCE www.ijircce.com 4143 Techniques of Node Localization in Wireless Sensor Networks: A Review Lovepreet Singh 1 , Sukhpreet Kaur 2 1 Research Fellow, Shri Guru Granth Sahib World University,Fatehgarh Sahib, Punjab, India. 2 Assistant Professor, Shri Guru Granth Sahib World University,Fatehgarh Sahib, Punjab, India. ABSTRACT- Wireless sensor networks (WSNs) are widely used in many environments and adverse terrains. The common problem in the wireless sensor network technology is localization problem. Most of the applications, the network collects the data without location information which is not very useful. Location information plays a vital role in both networking and in other domains of wireless sensor network. In this paper, review has been done on the localization algorithms and different taxonomy based on basic features. As wireless sensor networks are becoming an emerging technology, it is being used in many applications. We have also reviewed the important and fundamental factors which can validate the performance of node localization techniques. KEYWORDS: Wireless Sensor Networks; Localization Algorithm; Learning; Range. I. INTRODUCTION Wireless Sensor Network-As wireless Sensor Networks is an apparent technology it is being used in various applications. It is monitoring the physical real world entities by having communication without devices i.e. wireless known as sensor nodes. WSN techniques are useful for creating locate sensor nodes by taking the help of reference and beacon nodes. Beacon Nodes are the nodes which know their positions coordinate [10]. Some other nodes are localized by taking measurements like distance, Time of Arrivals (ToA), Time Differences of Arrival (TDoA), Angle of Arrival (AoA), Direction of Arrival (DoA) [11].However, position computation techniques like multilateration are getting used for computing the position of a node. Hence, some localization algorithms or technique is used for locating WSN nodes. There are many scenarios of WSNs applications which are present including military purposes, industrial purposes, household works, medical applications, natural disasters monitoring, and other emergency situations.[4] Figure 1.1 Components of WSN [3]