Design of Ku-Band Filters and Diplexer for a Heterodyne Transceiver Using Coupled Open-Loop Resonator Cells

This manuscript presents the design of two microstrip coupled open-loop resonator bandpass filters using a square loop-resonator, also know as splitring resonators, to be used in radio frequency Front-Ends. In addition, a microstrip diplexer using these cells is also detailed. The devices operate in k
_u
band, using the frequencies 11.7-12.2GHz, to the receiver channel, and 14-14.5GHz, to the transmitter channel. All the design is made considering low-cost industrial manufacturing tolerances. A Monte Carlo analysis is performed to verify the sensibility of the device due to the manufacturing capabilities. The measurement and simulation curves agree with a good level of acceptance, diverging each other in just 1.7dB in the passband, in the worst case.