Cooperative Location Acquisition of Mobile Nodes Without Direct Distance Measurement

In wireless networks composed of numbers of mobile wireless nodes, their location information is required to be achieved for fundamental network services such as routing of data messages and determination of server nodes providing various services such as name services and for supporting network applications based on locations of the mobile wireless nodes, for instance, sensor network applications and ITS applications. Until now, various methods for achieving distances between two mobile wireless nodes have been proposed; however, some of them requires too expensive devices and others achieves too low-resolution results. Most of the methods using RSSI of transmitted wireless signals between two mobile wireless nodes cannot provide enough high resolution due to large deviation of transmission delay and the multi-pass problem. This paper proposes a novel method for achieving distances between mobile wireless nodes by cooperation of 3 mobile wireless nodes with cameras and a device for measuring its own migration length. The cameras are only used for measuring angles with high accuracy between 2 mobile wireless nodes which are independent of their shapes, sizes and distances.