PIN Diode-Based Energy Selective Antenna with Coaxial Feeding

This paper proposes a coaxial-fed energy selective antenna (ESA) that incorporates four PIN diodes at the antenna corners to achieve energy-selective operation. A conventional coaxial-fed microstrip antenna operating in the S-band is first designed, after which the PIN diodes are integrated to realize the ESA. Under normal conditions without high-power microwave (HPM) exposure, the antenna functions identically to the conventional design. When subjected to HPM signals, the PIN diodes switch from the OFF state to the ON state, altering the antenna response. The proposed ESA effectively suppresses HPM signals, providing protection for circuits and systems.