Design of improved CMRC structure used in terahertz subharmonic pumped mixer

This paper presents a new improved compact, low-insertion loss, sharp-rejection, and easy to manufacture compact microstrip resonant cell (CMRC) structure [1] as microstrip or suspended-substrate microstrip lowpass filter (LPF) used in terahertz (THz) Subharmonically pumped mixer (SHM). In comparison to traditional high/low step-impedance filter used in SHM, this improved CMRC structure could shorten the circuit size by 50% and have advantages of better frequency selectivity property, as well as sideband rejection. By using suspended-microstrip transmission line structure, this improved CMRC structure improved its operation frequency up to THz. In addition, this improved structure also easy to manufacture through conventional lithography corrosion microstrip line technology. This improved CMRC structure's circuit topology structure, equivalent-circuit model and full wave electromagnetic field simulation results and the SHM circuit topology model using improved CMRC structure are given.