Compact L-Band Helical Antenna Designed For Pulsed Transmission

IS4S has designed, built, and characterized a compact L-Band helical antenna capable of transmitting RF output from a NLTL-based pulsed power system with ≥ 12 dB of forward gain. The IS4S Helical Antenna design has significant advantages for compact HPM design. This Antenna is <40cm in length with an 18cm backplane diameter and <7kg in weight, making the Antenna both compact and lightweight. The antenna was driven using a peak input power from 1MW to 10MW and was measured radiating a peak power of up to 25MW/m2 measured at a range of two meters on beam in front of the antenna in IS4S’s anechoic chamber. Testing of the antenna has included rep-rate operation with pulse repetition rate (PRF) up to 150MHz. The helical antenna design used is inspired by the work of J.R. Mayes and Dr. D.V. Giri, who used the helical antenna to explore high-power pulsed RF transmission in the 200MHz to 500MHz frequency region.