Optimized Transmission Electrical Broadband Impedance Matching for PolyCMUT

Electrical impedance matching in CMUTs requires a trade-off between bandwidth and achievable acoustic power. A solely power-optimized electro-mechanical coupling leads to long ringing and poor image quality. Our approach uses the Chebyshev filter network to obtain optimum performance in power while maintaining a wide bandwidth. The theoretical constraints for impedance matching circuits are explored and used to synthesize optimized matching circuits in a compact form, with good performance in both power and bandwidth. Experimental measurements validate the theoretical and simulation results.