A new phase-based filter (called improved analytical signal (IAS)) is introduced to detect buried unexploded ordnance (UXO) precisely from magnetic fields using the arcsine function of the ratio of the first-order vertical derivative of the analytical signal to the first-order derivatives of the x-. y-. and z-components of the analytical signal. The calculations are computed in the fr... https://tftoyes.shop/product-category/star-trek/