Maximum Gain of Array Antenna With Closely Placed Dipole Elements

A double integral operation is required to obtain gain in an array antenna in general, and only an omnidirectional antenna is represented in a closed form. In this letter, as a result of radio-wave propagation research, a closed-form expression that can be applied to a small dipole antenna or a half-wavelength dipole antenna is shown by using an equation applicable to spatial correlation in a three-dimensional multipath environment. In addition, the maximum gain characteristics of the half-wavelength dipole element linear array antenna are analyzed using the equation.