摘要 |
A method and apparatus for improving signals used for detecting conductive bodies in an area by means of an airborne electromagnetic survey system, comprising the steps of generating and transmitting an AC primary field signal, the frequency spectrum of which comprises a DC component or a low frequency component, and radiating this primary field signal to the said area and receiving induced secondary field signals which are generated by the said conductive bodies and further comprising the step of processing the received secondary field signals and representing the processed signals in order to derive information whether or not conductive bodies in the said area are present. |