Range-free localization algorithm using local expected hop length in wireless sensor network

Node location information plays a major role in wireless sensor network (WSN) location-aware applications. This paper analyzes the problem in estimation of expected hop length in multi-hop sensor network. Calculation of the traditional expected hop length is based on average node density over the network. Although the expected hop length benefits a good location accuracy in a uniformly distributed high node density case, the location accuracy degrades when we consider low node density in the network. In this paper, we study the drawback of the conventional expected hop length that deteriorates the location accuracy and we propose the local expected hop length LEHL based on local node density of each sensor node. The core idea of using LEHL is to improve location accuracy by considering the appropriate expected hop length for real network deployment. Simulation results show that our proposal outperforms the conventional localization algorithm using expected hop length (LAEP).