Multilayer-substrate integration technique of air-filled waveguide circuits

This paper presents Air-Filled Substrate Integrated Waveguide (AFSIW) intended for the design of high performance and low-cost systems based on multilayer Printed Circuit Board (PCB) process. The top and bottom layer may make use of an extremely low-cost standard substrate such as FR-4 on which base-band or digital circuits can be implemented so to obtain a self-packaged and compact millimeter-wave integrated system.