Kolloquiumsvortrag: 29. November 2022, Jonas Thomann (Betreuer: A. Djanatliev)
Evaluation of GALILEO FEC on the OSNMA Protocol
There is a wide range of speeds vehicles can travel at and a plethora of possible burst outage scenarios caused by bridges or tunnels. To determine the performance of Galileos Open Service Navigation Message Authentification (OSNMA) Protocol the focus of this thesis is on a single burst error within the signal. For a given burst error length I determined the most likely number of faulty pages after decoding and for a given number of pages the resulting OSNMA success rate. Together this data was used to map outage times to OSNMA success rates. From there I approximated the bridge width depending on the vehicle speed.
How good OSNMA performs is almost synonymous with how successful the Forward Error Correction (FEC) decoding is. Therefore, I compared different decoding approaches. Critical applications need a OSNMA success rate of 100%. Using a more elaborate receiver much better results (nearly three times better) can be achieved. While in an urban scenario with a speed of 50 km/h a naive receiver could only tolerate a 2m wide bridge. A more elaborate receiver can tolerate up to 8m. Less critical applications can tolerate much higher bridge widths. Additionally the relative difference between a naive and elaborate receiver becomes much smaller for less critical applications. Thus, investing in a receiver with better FEC decoding capabilities will only result in notable performance gains for highly critical applications where a 100% OSNMA success rate is required.
In summary, since OSNMA performance almost solely depends on the error correction capabilities of the receiver, the results of this thesis indicate a moderate tolerance to burst errors: commonly occurring bridges could be tolerated at high speeds but can’t be tolerated at lower speeds as would occur in urban scenarios. However, when considering further improvement possibilities OSNMA could be made very robust, also being able to tolerate most bridges in urban scenarios with lower vehicular velocities.
Zeit: 10:15 Uhr
Ort: Raum 04.137, Martensstr. 3, Erlangen
Meeting-ID: 631 7461 3617