Design of an Optimized Space Diversified Antenna Arrays for Extended FM-RF Propagation

Most Frequency Modulation broadcast stations are stacking antennas in order to extend the radiation of energy and propagation of signal. This paper presents a design of an optimized shunt-fed FM broadcast antenna also with a circular polarity for weather infiltration and no constraint of the orientation of transmitter and receiver. The method primarily includes the optimization of the relative spacing of dipoles to exhibit a circular azimuth pattern, axial ratio requirement for circularly polarized antenna and the gain in far field. The circular pattern shaping method uses a uniform linear array of two elements and the principle of array multiplication. Two control factors are being utilized to shape the radiation pattern as follows: the relative distance spacing, separating the two elements and their excitation phase difference. In the optimization process, a more accurate and consistent solutions like Global Response Surface Method was used. GRSM yields the most optimal objective value and it follows to determine the optimum values of the parameters in the current design. Results show that the pattern produced by the proposed method can resemble a circular form and exhibited an increased in antenna gain as compared to the commonly used shunt-fed slanted V dipole antenna. The results of the optimized design of a FM antenna and its characteristics are validated using an antenna simulation software.