Abstract: Because magnetic dipole field is mixed with geomagnetic field, a geomagnetic localization method aided by vehicle draft depth was put forward to solve difficult acquirement of magnetic field magnitude, where the vertical position of vehicle relative to target can be calculated by two measurements of draft depth and magnetic gradient. The shortage of vehicle moving in vertical direction endlessly for continuous localization can be solved by a localization method using magnetic moment of the target, where the position of vehicle can be calculated by a nonlinear equation with position parameter composed of known magnetic moment and magnetic gradients. The concrete steps of continuous localization algorithm were given, and the numerical simulations prove the feasibility and higher precision of the localization algorithm.  

Key words: underwater localization, vehicle draft depth, magnetic moment, magnetic dipole, numerical continuation