Adaptable tracking with respect to accuracy - energy - robustness

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During the first phase of BATS the tracking functionality was developed by TP5 and TP6. A tracking concept was designed, which provides field-strength based low energy tracking covering the complete area of the sensor net - focus of Tracking4BATS (TP5) - and increased accuracy in limited areas, based on phase coherent measurements - focus of Scalability4BATS (TP6). The close cooperation with the Fraunhofer IIS has to be underlined. Without the collaboration the design of the base station platform (OAK board) and the particular positioning antennas would have been hardly possible. Robustness4BATS, this project application, has to overcome limitations regarding the reliability of the computed trajectories. The limitations are due to multipath propagation, as has been observed during the field trial in Panama. Multipath propagation has to be detected, mitigated and preferably exploited, e.g. by augmenting the databases with multipath dependent fingerprints for better positioning. The two design criteria of phase 1, energy consumption and accuracy, have to be completed by a third criterion: robustness. The sensor data fusion has to render possible a user-driven balance among these conflicting goals. Quality indicators have to be devised to characterize the energy consumption, the accuracy and multipath propagation. The concept of two-tone signals has to be extended to multi-tone signals in order to measure the frequency response of the channel. The new signal design has to facilitate an environment-adaptable spectral power density of the transmit signal: for line-of-sight propagation accuracy should be maximized, in the case of multipath propagation robustness. This adaptability is an objective not yet investigated in Global Navigation Satellite Systems like GPS. It is central to the scientific outcome targeted at. Not only simultaneous multi-tone signals, but also frequency hopping shall be included, since commercial low-energy transceivers apply this kind of signals. To address these issues, the base stations including antennas have to be modified with the support of the Fraunhofer IIS.