Miniaturization of microwave antennas through metamaterials with enhanced radiation performance

This paper presents the design, fabrication, and characterization of five CMOS-compatible microstrip patch antennas on high-resistivity silicon substrate (HRSi) in two different configurations: (i) a classical patch antenna designed to work at 10 GHz and used as a reference; (ii) the same patch antenna but with different numbers of unit cells (i.e., one, three, five, and nine) in the back reflector, each cell being a complementary split ring resonator (CSRR). The simulation results show an improvement of the CSRR-based antenna in comparison with the reference patch antenna, in terms of both gain G and radiation efficiency η: at 7.5 GHz, G increases from -6.29 dB to 1.87 dB and η is 7× times higher, while at 8 GHz G increases from -2.81 dB to 2.33 dB and η is 3× times higher. The experimental results of the CSRR-based antennas, in comparison with the reference one, demonstrate the following: (i) a gain performance improvement with more than 17 dB at 8.2 GHz, (ii) a reduction of the resonant frequency with almost 26% at 8 GHz, (iii) a multiband antenna working in the large frequency range 7.5-12 GHz with improved bandwidth in comparison with the reference antenna, i.e., 1365 MHz instead of 35 MHz.