Microwave absorbing properties of the Archimedean plane spiral antenna array/epoxy resin composites

Microwave absorption of composites containing the Archimedean plane spiral antenna arrays was investigated. The results show that the absorptivity greatly depends on increasing the magnitude of resistance connecting the two arms of the spiral antenna, first increasing and then decreasing. When the magnitude of resistance is 510 Ω, the bandwidth below −10 dB is 10.4 GHz (making up 86.7% of the frequency range 6–18 GHz), and the minimum reflection loss reaches −29.6 dB. The absorbing properties of composites fall with decreasing the initial radius and arm width of the spiral antenna.