Cold & hot tests of an S-band antenna for high power microwave systems

We present results of simulation, fabrication, and testing of an S-band narrow-wall longitudinal slot antenna designed for high-power-microwave (HPM) systems. A key aspect of the proposed antenna structure is the use of longitudinal slots in the narrow-wall of a rectangular waveguide as elements of the slot array to enhance the power handling capability of the antenna. Cold test of the antenna showed excellent agreement with the simulated return loss and radiation patterns. The radiation pattern measured in high power testing with a source power of 0.8MW also demonstrated good agreement with the simulated radiation pattern. This source power level is slightly below the predicted maximum input power handling capability of 1.15MW, at high elevation (in Albuquerque, NM). This work demonstrates that this narrow-wall longitudinal slot antenna is well suited to HPM applications.