A Lithium Niobate MEMS-coupled Matching Network for BFSK Modulated Signal Amplification in Spectrum Monitoring Applications

This paper reports on a novel MEMS-based matching network architecture specifically designed for the passive amplification of Binary Frequency-Shift Keying (BFSK) modulated signals. The topology is modeled according to classical filter theory to achieve two gain peaks equidistant from the resonance frequency. Two high performance, capacitively coupled lithium niobate microacoustic laterally vibrating resonators operating around 200 MHz are then utilized to validate the architecture. Numerical simulations based on the measured devices' admittance are performed to assess the circuit S-parameters and the passive voltage amplification provided by the matching network to a capacitive load of 1 pF. Finally, a printed circuit board prototype implementing solidly mounted ceramic capacitors and wire-bonded resonators is tested to experimentally validate the concept.