Abstract: To address the challenge of balancing miniaturization with overall performance (gain, efficiency, and bandwidth) in low-frequency dielectric small antennas, a design approach based on a novel ferrocene-based organic magnetic substrate, JV5, through simulation analysis is proposed in this study. This material exhibits high permeability and high permittivity, making it suitable for developing low-frequency, broadband, and miniaturized antennas. Using a simplified structural design, three broadband, miniaturized, and high-frequency organic magnetic microstrip antennas operating in low-frequency bands (50 MHz~70 MHz, 50 MHz~90 MHz, and 100 MHz~120 MHz), which were unreported previously, have been successfully developed in this study. Simulation results demonstrate that these antennas achieve excellent broadband and miniaturization performance while meeting requirements for gain, axial ratio, and voltage standing wave ratio. Furthermore, the simulations indicate that the JV5 substrate can be utilized for skywave over-the-horizon radar target detection and wave excitation detection, providing a novel and effective solution for miniaturizing very low-frequency (< 30 kHz) antennas.