Experimental Study of Ultra-Wideband Interference Attenuation in a Flexible Printed Circuit Board Cable

The performance and functionality of radio electronic equipment depends on various factors including external. One of them is electromagnetic interference, in particular ultra-wideband interference. The paper considers the protection of radio-electronic equipment from the impact of ultra-wideband interference by using modal filtering in flexible printed cables. These cables are feature by a high degree of design and application diversity, which makes them particularly attractive for providing interconnections in modern electronic equipment. This material has a relatively high dielectric permittivity, which allows for a higher per-unit-length mode delay. We fabricated a flexible printed cable to conduct a full-scale experiment and studied it in the frequency and time domains. To validate the experimental studies, we performed quasistatic simulations. The experiment demonstrated that the ultra-wideband interference can be successfully attenuated in the cable, and the maximum attenuation was 3.6 times of the original value, with a bandwidth of 118 MHz. The discrepancy between the simulation and experimental results can be attributed to the unaccounted influence of coaxial-microstrip and coaxial transitions, as well as the discrepancy in dielectric electrical characteristics.