ABSTRACT
The chapter of the book is devoted to the basic principles underlying the rigorous methods of analysis and synthesis of antennas. Among them, the method of integral equations for the current, which allows to calculate the current along antenna wires and determine all electrical characteristics of an antenna, starting with a simple linear radiator and moving on to complex one consisting of simple elements. For the analysis of a curvilinear radiator, the antenna is divided into simple rectilinear and curvilinear sections located along different coordinate axes. Points of the new sections must coincide with projections of points of the original antenna.
In accordance with the oscillating power theorem, the propagation of electromagnetic energy is understood as the transfer process of an energy transfer through the boundary of an enclosed space in which the source is located. The energy flow consists of two parts: active power, equal to the average value for the period of oscillation, and oscillating power varying with double frequency. Their values are determined by the amplitudes and phases of the instantaneous values ??of physical quantities included in the Maxwell equation.
The chapter successively examines well-known methods of antenna analysis, their advantages and disadvantages. For the physical interpretation of obtained results, the book uses the equivalent long line method, and the first chapter provides circuits of long lines for metal antennas with distributed and concentrated loads. The circuits are given, which were proposed for analyzing the mutual influence of horizontal systems of wires, parallel to the ground. Later they were used also for vertical wires.
