An Architecture for Location Tracking Using SIP

Location tracking in wireless networks has many applications, including enhanced network performance. In this report we investigate a new SIP-based architecture for wireless networks that allows for the fusion of different positioning technologies (GPS and Particle Filters). The architecture is specifically designed for outdoor users possessing intermittent GPS availability, a characteristic commonly found in real outdoor wireless networks. The architecture also includes the novel use of a user profile database in the particle filter algorithm, which we show can lead to factor two gains in position accuracy. Implementation of our architecture is described, and simulations of its performance in the multi-user setting are provided. We show how the architecture´s effect on network operations is minimal. The architecture we propose here, builds on our already deployed particle filter tracking algorithms in wireless networks.