Ring Resonator Loaded Log-Periodic Antenna for IEMI Detection Application

A patch-added planar log-periodic ring resonator meander dipole array (PPLPMDA) antenna with dimensions $\mathbf {27 \times 27 \times 0.16\ }\mathbf {\mathrm {cm}}^{\mathbf {3}}$ is developed to detect an intentional electromagnetic interference (IEMI) signal in the frequency range of 0.5–2 GHz. A meander line concept has been utilized in the radiator section to lower the antenna size. The lateral dimension of the PPLPMDA antenna is smaller by 36.65% and the horizontal dimension is smaller by 10% extra space here? compared to the conventional planar log-periodic dipole array antenna. The patches have been included for certain dipoles to get a high and nearly stable gain in the entire operating frequency range. The fabricated PPLPMDA antenna is tested in terms of S-parameters, far-field radiation performance, IEMI sensing, etc., and witnessed good agreement between simulation and measurement results. The measurements show that the PPLPMDA antenna has an average gain of $\mathbf {4.25 \pm 1.25}\mathrm {\ }\mathbf {\mathrm {dB}}$ , a reflection coefficient $| \mathbf {S}_{\mathbf {11}} |\mathbf {\leq } \mathbf {10}\mathrm {\ }\mathbf {\mathrm {dB}}$ , and a stable radiation pattern. Compared to the existing designs, the proposed PPLPMDA antenna has a compact nature without sacrificing the far-field performance, which makes it more suitable for system-level integration as a nonpowered passive sensor to detect IEMI signals.