Background: Antenna can serve as transmitter or receiver of electromagnetic energy
(power). Circular path antenna as a single and as an array microstrip antenna will be used in this paper.
Methods: Five array microstrip antennas with different amount of patch will be designed to get different
amount of return loss variables, as well as discovering its effect on the power efficiency of the antenna.
Results: By discovering the correlations between these two variables, we can make antenna more
efficient in its usage. Designing and simulation of these antennas will use FR4 substrate and the
frequency set in 2.4 GHz.
Conclusion: The amount of the return loss has successive values, starting from -14.981175 dB, -
17.090297 dB, -19.620465 dB, -25.962626, to -34.316575 dB, while the successive value of Power
Efficiency starting from 0.911294871 up to 0. 95411176. It is proved that the lower return loss, the
higher power efficiency.