This paper presents the Moving Long Base-Line. (MLBL) navigation concept as well as simulation and experimental results. This multiple vehicle navigation technique consists of using vehicles fitted with accurate navigation systems as moving reference transponders to which other vehicles, fitted with less capable navigation systems, can acoustically range to update their position. Reliable acoustic communications are mandatory for the real time implementation of this navigation scheme. However, while enabling MLBL, acoustic communications reduce the range update rate and introduce delays that need to be dealt with in the navigation algorithm. Simulation results show that relative navigation accuracy between vehicles can be maintained although the absolute navigation accuracy of each vehicle decreases over time. This is a key enabling factor for AOFNC missions where contacts are called by vehicles and re-acquired by other vehicles in real-time.
