The objective of this paper is to review the variety of systems from different points, especially in terms of signal structure, to analyse advantages and limitations of many existing systems and to suggest an approach that can make possible the ability to use the achievements in all of them during developing a new one. An attempt to realize this lead to the appearance of the system EQUATOR. The practice of using the system EQUATOR in both isolating and conductive environment for different type of targets fully confirms effectiveness of this approach.