Advances in High-Frequency PCB Materials

Traditionally, RF/microwave printed circuit board applications were developed based on the needs that came out of the military market. Applications like radar and guidance systems were operating at frequencies where traditional printed circuit board (PCB) materials like epoxy/woven glass did not have the properties — mainly tight dielectric constant control and low dielectric loss — that allowed them to be used at frequencies in the +1GHz range. Instead of PCBs, designers had to use waveguide structures as the first RF/microwave circuits; however, this meant bulky and