ABSTRACT
The chapter of the book is devoted to the results of solving the problem of creating wide-band and wide-range antennas. The problem was solved by means employment of concentrated loads (capacitive and resistive) included in the radiator wire and creating an in-phase current in it with a given law of the distribution of a current amplitude along the antenna. The solution is based on an understanding of an advantage of the in-phase current and Hallen's hypothesis about the usefulness of capacitive loads, the values of which vary along the radiator according to a linear or exponential law. The chosen approach confirmed Hallen's hypothesis and demonstrated the effectiveness of the proposed approximate methods for calculating capacitive loads: the method of an impedance long line and the method of a long line with loads. The loads calculated by these methods were used as initial values for the synthesis of plane and three-dimensional antennas by the methods of the mathematical programming.
The creation of in-phase linear and V-radiators, which in a wide frequency range provide a high level of matching an antenna with a cable and a shape of a radiation pattern required to increase the communication range, shows that the use of capacitive loads can significantly improve all electrical characteristics of the antenna. The new analysis method, called by the author the method of electrostatic analogy, makes it possible to compare the electromagnetic fields of high-frequency currents of linear radiators with electrostatic fields of charges located on linear conductors and to improve the directional characteristics of director-type and log-periodic antennas.
