Improved particle filtering by exploring nomadic movements

Network operators have a keen interest on knowledge about the coverage of their network in indoor environments. Mobile users use the mobile network indoors about 80% of their time compared to outdoor. To identify coverage gaps it requires precise knowledge about the environment itself and the whereabout of the mobile terminal. This knowledge is lacking for two reasons. First the network driven time-based location solutions of the user is rather inaccurate for reasons like multi-path propagation or inaccurate synchronization. Furthermore, the indoor environment itself remains normally unknown for the network operators. However, the high density of users in indoor environments invites to explicitly use the potential peer-to-peer links between mobile terminals themselves. This would allow to position the mobile terminals relatively to each other. Positioning by using the peer-to-peer link is called cooperative positioning. This paper investigates the behavior of a distributed particle filter using nomadic movement behavior of the tracking objects.