Apparatus and method for determining at least one electromagnetic quantity

Abstract

The present invention relates to an apparatus () for determining at least one electromagnetic quantity characterizing an electromagnetic property of an object, in particular a human body, wherein said object contains magnetic particles. The apparatus () applying the known principle of Magnetic Particle Imaging (MPI) comprises selection means for generating a magnetic selection field () having the known field pattern showing a field free point (FFP), drive means for changing the position in space of the FFP by means of a magnetic drive field, receiving means for acquiring detection signals depending on the magnetization of the magnetic particles within a field of view () and a reconstruction unit () for reconstructing a particle distribution quantity depending on the detection signals. The apparatus () further comprises a control unit () for controlling the receiving means for acquiring a first set of detection signals corresponding to a first drive field frequency and a second set of detection signals corresponding to a second drive field frequency, with both drive field frequencies differing from each other. The control unit () further controls the reconstruction unit () for reconstructing a first particle distribution quantity depending on the first set of detection signals and a second particle distribution quantity depending on the second set of detection signals. The apparatus () further comprises a determination unit () for determining the electromagnetic quantity depending on the first and second particle distribution quantity. The present invention further relates to a corresponding method as well as to a computer program.