Theoretical and experimental investigations on optimization of the received power of a monopole antenna

Abstract

Antenna is an essential component of telecommunication devices. Recently, the antenna has been used as a receiver in the rectenna solar cells as well as a vital component of cellular mobile telecommunications. The power of the received signal may depend on the physical shape of the monopole receiving antenna. The optimization of antenna's geometry is essential to improve the antenna performance as a receiver. It is widely accepted that the physical length of the monopole antenna; with one fourth of the incident wavelength; possesses an optimal efficiency. In the current study, a power equation based on a recently modified electromagnetic (EM) wave theory has been derived. The proposed formula has been used to calculate the optimum length of the monopole antenna to optimize the received power by the antenna. The angle between the direction of the antenna's plane corresponding to the direction of the propagation of the EM wave has been considered. some experimental investigations have been considered to confirm our theoretical investigations. In our experiment, the output voltage has been considered as a good indication of the harvested energy of the monopole antenna.

Antenna designing for efficient rectenna solar cells

“…Let us consider a wire monopole antenna exposed to EM radiation. The free electrons of the antenna materials get a two dimensional oscillating force [26][27][28][29] having a frequency of the EM radiation for 90 degrees phase difference [30] between the electric and magnetic fields. This oscillation of the carriers is the AC power of the antenna.…”

“…Although the theoretical investigation shows that, the received power depends on the direction of the antenna corresponding to the EM wave propagation in practice. The received power found to have a less notable change when the direction for non-polarized (practical) EM radiation is changed [26]. The sunlight is of shorter wavelength and un-polarized EM radiation, so the light intensity and frequency as well as energy are the main factor to generate much electric power.…”

“…Then, a small voltage as AC with very high frequency is produced in the antenna. The process of electric power generation in the antenna has been described elsewhere [26]. In the rectenna solar cell there is a possibility to mitigate the power [23] in the antenna by different phases of EM wave in different places for very short wavelengths.…”

“…Then the received power depends on the length of the antenna. The optimum length of the monopole wire antenna is λ/4 [26,31,32]. Here, λ is the wavelength of the EM waves.…”

Ring slot CP antenna for the hybrid electromagnetic solar energy harvesting and IoT application

“…To improve the voltage circuit output's accuracy with specific components, so the optimation of inductance and capacitance of the configuration are also represented in the circuit configuration design in Figure 5, as shown in Table 1. The design voltage multiplier setting helps in increasing the voltage sensitivity [31]. The antenna's EM radiation is received by the rectifier circuit, which converts it to direct current (DC) power.…”