Energy efficient base station antenna: Impact of antenna matching based on substrate material

Increase in number of base stations in order to enhance coverage for the ever increasing number of mobile network users leads to increase in energy required for mobile network operation. Antenna mismatch leads to power loss which further lowers the energy efficiency of mobile network. Microstrip antennas for base station were designed with different substrate materials based on transmission line model to investigate the impact relative permittivity or dielectric constant on antenna matching. The calculated and simulated values of voltage standing wave ratio (VSWR) which is one figure of merit for antenna matching show direct proportionality. Better matching was obtained by using substrate of low dielectric constant (other than air) such as duroid with VSWR of 2.3 and power loss of 10.5%. The maximum power loss of 92.8% was given by Microstrip antenna designed with Silicon substrate of dielectric constant 11.9 and VSWR of 28.0. The paper recommends that matching network should be employed in base station antenna design so as to handle other antenna components that might detune the antenna thereby reducing the energy efficiency.