Distributed location estimation method for mobile terminals based on SOM algorithm

Abstract

AbstractAd hoc networks have excellent capabilities for data transmission in an environment with an incomplete communications infrastructure, and in mobility and portability of terminals. Routing protocols between terminals in an ad hoc network can be broadly divided into location‐aware routing, based on location information on the terminals, and non‐location‐aware routing, which is not based on location information. In the former, routing can be made accurate and easy by effectively utilizing location information. Hitherto, the use of the global positioning system (GPS) has been most often treated as the means of acquiring terminal location information. However, in location estimation by GPS, electromagnetic waves from multiple location estimation satellites must be received, and the method cannot be applied effectively in an environment in which that condition is not satisfied. This paper proposes the following method of location estimation. Fixed access points whose absolute locations are already known are placed in the network. Then, by using self‐organizing maps (SOM), the mutual location information among the terminals is organized, and the location of the home terminal is successively inferred. The feasibility and accuracy of estimation in the proposed method are examined by a computer simulation. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(4): 73–81, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10098