Design of Low Profile ATFSS and Antenna With In-Band and Out-of-Band RCS Reduction

Stealth is a very important property for antennas, not only in-band stealth, but out-of-band stealth will also greatly affect the overall stealth of antennas. Thus, a novel low-profile absorbing/transmitting integrated frequency selective surface (ATFSS) is proposed in this article, and then an antenna with in-band and out-of-band radar cross section (RCS) reduction is designed by combining it with an array antenna with integrated radiation and scattering. The profile height of the novel ATFSS is only 3.6 mm, and the gain of the in-band and out-of-band RCS reduced antenna is greater than 17.5 dBi and its insert loss is less than 1 dB in 8.5–10 GHz. Meanwhile, the antenna can achieve significant RCS reduction in the out-of-band of 4.8–8.5, 11.2–15.1 GHz, and in the in-band of 8.5–10.5 GHz. Excellent agreement is obtained between simulation and measurement for the in-band and out-of-band RCS reduced antenna. Such a method not only can significantly reduce the profile height of the traditional ATFSS, broaden the low detectable bandwidth and enhance the invisibility of the antenna, but also maintain the high gain radiation characteristics of the antenna, which has important practical application value.