2 wt% V2O5-enhanced microwave dielectric properties of Ba3Ti4Nb4O21 ceramics for miniaturized cylindrical dielectric resonant antenna application

Currently, microwave communication devices are rapidly evolving toward miniaturization, high stability, and cost-effectiveness. However, traditional microwave dielectric ceramics with moderate dielectric constants require excessively high sintering temperatures and exhibit poor microwave dielectric properties. Here, 2 wt % V 2 O 5 -modified Ba 3 Ti 4 Nb 4 O 21 (BTN) ceramic is prepared via solid-state reaction method. The sintering temperature of the BTN ceramic is successfully reduced from 1270°C to 975°C. This ceramic exhibits excellent microwave dielectric properties ( ε r = 47 (@5.78GHz), Q × f = 15,841 GHz (@5.78GHz), τ f = + 14.3 ppm/°C). Using XRD, SEM, EDS, Raman spectroscopy, and first-principles calculations, the changes in the microwave dielectric properties of BTN ceramics and their effects are elucidated. Based on this ceramic, a slot-coupled side-fed cylindrical dielectric resonant antenna was designed and investigated by full-wave electromagnetic simulation. The simulated antenna achieves excellent impedance matching and polarization isolation while maintaining a compact size: simulated center frequency is 6.74 GHz, BW = 200 MHz, and S 11 = -36.26 dB. This work demonstrates that BTN + 2 wt % V 2 O 5 microwave dielectric ceramics hold great potential for development in the field of 5G microwave communications.