International audienceWith the emergence of Smart City concept, Wireless Sensor Networks (WSNs) become one of the key technologies for instrumenting the city, and thus providing its inhabitants with various services meant to improve their daily life. One of the identified applications is Smart Street Lightning, where the lamps are in a mesh network for remote control and maintenance purposes. This paper proposes Ubiquitous Navigation System (UNS), a WSN-based navigation system, which takes benefit from the Smart Street Lightning system to provide a local navigation service. The positioning part of the system uses Angle of Arrival (AoA) measurements to estimate the vehicle position on the map. Based on a realistic network scenario, extracted from a city map using Google Maps, we study the performance of Triangulation using AoA in a smart urban environment that exhibits topology related constraints. Simulations results show that such constraints lead to particular spatial distribution of the anchor nodes that affects both positioning accuracy and beacon packets reception rate. We also propose and evaluate the use of the network communication range as a technique to mitigate the effect of geometric dilution of precision (GDOP). The simulation results show that this technique successfully detected GDOP-affected positions and thus significantly enhanced the positioning accuracy