SYNTHESIS METHOD OF VIBRATOR ANTENNAS WITH REACTIVE INSERTS

Abstract

A new approach is proposed for investigating the electromagnetic properties of a specific class of periodically loaded structures (vibrator antennas with capacitive inserts), which is characterized by relative simplicity and sufficient accuracy. It allows obtaining analytical solutions, thus avoiding the difficulties associated with numerical solutions. At the same time, the obtained solutions can be used in iterative methods for numerical analysis of electromagnetic properties of periodically loaded structures and antenna devices containing these structures. The solution of the problem of electromagnetic energy propagation in a uniform two-conductor transmission line with reactive inclusions is presented. Its solution has revealed new regularities and provided a fresh perspective on the calculation of vibrator antennas with capacitive inserts. Studies on the frequency characteristics of antennas with capacitive inserts have identified three extreme cases of current distribution: exponential, sinusoidal, and linear. Expressions for calculating internal and external characteristics of such antennas have been derived, and dependencies of their electrical characteristics on geometric dimensions have been established. Recommendations for the rational selection of capacitance values and their locations have been formulated. A calculation method for vibrator antennas with capacitive inserts has been developed, which involves the rational use of dispersion properties of such structures in the frequency domain to create wideband antennas with inserts. For the operation of specialized radio equipment, samples of vibrator antennas with two or three capacitive inserts have been manufactured and studied. The results of testing such antennas have shown that their gain at frequencies close to the critical value exceeds the gain of a quarter-wavelength radiator by two or more times, thus increasing the overall efficiency of the developed antennas.