Low-Pass Filtering Cable Design Utilizing Defected Conductor Layer with Pi-Shaped Defected Structure

Insulated electrical wires coated with a specific defected conductor layer exhibit filtering advantages, making them suitable for reducing electromagnetic interference conducted by cables in complex electromagnetic environments. The etched-out pattern on the defected conductor layer serves as a distributed filtering circuit, equivalent to a lumped circuit added to the transmission line circuit of the cable. In this paper, we present a low-pass filtering cable designed using a defected conductor layer with five cascaded Pi-shaped resonators. The defected conductor layer is fabricated on a polyimide film substrate, and simulation and experimental results demonstrate that the designed low-pass filtering cable exhibits a sharp transition band and an ultra-wide stopband, effectively achieving its filtering function.