A high-Q tunable grounded negative inductor for small antennas and broadband metamaterials

This paper presents a broadband high-Q tunable negative inductor based on a gyrator topology. In order to reduce the risk of instability and to increase circuit bandwidth, simple inverters are used as transconductance amplifier. A complete stability analysis and careful circuit design details using SOI 180 nm technology are presented. Post-layout simulations results show a negative inductance variation from -24 nH to -13.7 nH. For a bandwidth from 10 MHz to 1 GHz, inductance value error remains under 12.5 %. Circuit power consumption is 16 mW; and area consumption is 120 μm by 84 μm.