Direct Antenna Binary Phase-Shift Keying Through Ferrimagnetic Loading

This study proposes the use of Yttrium Iron Garnet (YIG), a ferrimagnetic material, in the form of a small ferrite rod, to load an X band open-ended waveguide antenna. It was observed that the phase of the radiated signal from the YIG-loaded antenna can be tuned by adjusting the magnetic bias field strength. By selectively switching between two magnetic bias fields that give 180-degree phase difference in the radiated signal, a direct antenna binary phase shift keying (DA-BPSK) is realized. Simulation results from HFSS and ADS are used to demonstrate the feasibility of the idea. Such direct antenna modulation (DAM) system can be instrumental for on-chip electrically small antennas.