Airborne electromagnetics: dealing with the aircraft speed

It is no secret that the solution of Maxwell's equations depends on the coordinate system. But in current studies, the dependence of the solution on both the speed of the transmitter and the speed of the receiver is usually not discussed. In this article, I present an analysis of such an effect on the readings of an alternating magnetic field receiver and on the secondary field. I have found that the effect of the receiver's motion is critical. I have proposed a compensation method now implemented in some systems, after which the measurements of a moving receiver can be considered as signals of an equivalent stationary receiver at the current position. It is also shown that the field distortions proportional to the aircraft speed are related to the flight altitude and the electrical conductivity of the medium. I analyzed data from the EQUATOR airborne electromagnetic sy stem obtained over the sea surface. It is shown that the influence of speed is much less than the influence of restrictions on the environment model, which are imposed during the inversion of airborne electromagnetic data.