## 1 Introduction  
Communication in high-frequency (HF) bandwidths--i.e., 3-30 MHz--can be transmitted without the use of a satellite up to distances of thousands of kilometers by ionospheric reflection. Accordingly, the HF band is utilized in military operations, for communications during disasters and in rugged mountain terrain [1]. In addition to the HF band, very-high-frequency (VHF) and ultra-high-frequency (UHF) bands are also used in many applications, such as unmanned aerial vehicles (UAVs) [2]. However, due to the long wavelengths of the HF, VHF and UHF bands, the size of the antenna becomes bulky. Accordingly, various miniaturized antennas which operate in the HF, VHF and UHF bands have been studied [3; 4; 5; 6; 7; 8; 9; 10; 11; 12]. Nevertheless, the sizes of these antennas remain large, along with unfavorable height measurements, complicating their use in relatively small manpacks. Therefore, in addition to additional miniaturization efforts, low-profile characteristics must also be secured in consideration of aerodynamic and mobility capabilities. As a means of designing an antenna with such characteristics, one viable technique is to apply the artificial magnetic conductor (AMC) of a periodic structure, as the properties of an AMC are similar to those of a PMC (perfect magnetic conductor), which does not exist in nature [13]. Given that the AMC has in-phase reflection characteristics within a specific frequency bandwidth, it can realize low-profile characteristics and can cause the impedance matching of the antenna to have broadband characteristics [14]. In particular, several studies have attempted to design AMCs that operate at low-frequency bands with long wavelengths compared to the frequency, such as the VHF/UHF bands [15; 16; 17]. In one study [15], a non-foster negative inductor was used to design an AMC that operates in the broadband range within the VHF/UHF bands. However, this AMC cannot cover the HF band and is somewhat complicated to fabricate. In another study [16], by placing an airgap between the patch and the ground plane of the unit cell, the AMC operates with broadband characteristics within the UHF band. The antenna with the designed AMC has a low-profile but cannot work on the HF band. An EBG (electromagnetic band-gap) designed by applying a ferrite material was also introduced [17]. This designed hybrid EBG has an operating frequency bandwidth ratio that exceeds 22:1 but operates at frequencies higher than 170 MHz; i.e., the VHF band.  
In this letter, a low-profile, ferrite-loaded Spidron fractal dipole antenna for manpack applications is presented. First, by applying a ferrite material with a high permeability value, a compact AMC that is capable of operating within a broad frequency band within the HF/VHF/UHF bands was designed [18]. The dipole antenna integrated with the AMC has a Spidron fractal shape with a quasi-self-complementary structure. Previously, Spidron fractal geometries have been introduced in various papers [19; 20]. By combining the miniaturized wideband AMC and the quasi-self-complementary dipole antenna, the proposed antenna with the designed AMC can operate in the HF/VHF/UHF bands. ANSYS high-frequency simulator (HFSS) software was used to conduct all simulations in this paper. The configurations of the designed AMC and the antenna are introduced in Section 2, and the results of the comparison between the measured and simulated results are presented in Section 3. This paper concludes in Section 4.