Localization in Anchor less Wireless sensor Network

One of the critical components in wireless sensor networks is the locating sensor nodes. We discuss the various localization techniques and categorize them based ranging and combination. An important problem in sensor networks is the localization of individual nodes, i.e., each node's awareness of its position relative to the network. Using a set of pre-existing anchors with globally known positions may not always be available and cost effective. Mobile wireless sensor networks with no (or less) GPS receiver, has different localization. We use some method to relief localization problems. We explore mobility problems and solutions in case we have less GPS receivers. We describe several mobile systems and compare them together. Then we describe mobility models and challenges. Finally we show comparison of localization technique and mobile systems on table.