A New Linearly Tunable RF MEMS Varactor with Latching Mechanism for Low Voltage and Low Power Reconfigurable Networks

Abstract

A new electro-thermally driven high Q tunable RF MEMS capacitor is proposed in this paper. The tuning mechanism of the varactor is chosen to obtain tuning; hence the capacitor has linear tuning range. In order to satisfy the low voltage operation of the varactor electro-thermal actuators were chosen as the drive and latching mechanism. However, those actuators consume lots of power, accordingly, in order to suppress that shortcoming a true mechanically latching mechanism is proposed which considerably decreases the total power consumption of the varactor. In order to investigate important operational aspects of the proposed varactor, different FEM simulations are carried out. The results are as follow; the Q-factor is 43.39 at 1 GHz for a 0.46 pF capacitance value. The tuning ratio is 1.17:1 and self-resonant frequency is 16.61 GHz. The propose varactor works by applying an actuation voltage of 3.1 V and consumes a power of 180 mW for about 2.7 ms for each tuning steps. The proposed varavtor of this paper can be a promising choice for low lass and low power RF tunable networks.