Bessel beams (BBs) recently gained much interest thanks to their limited-diffractive and self-healing properties. Resonant BB launchers are compact, low-profile, cost-effective devices able to generate such field distribution in the microwave and low millimeter-wave frequency ranges. However, modern applications call for radiating devices able to focus the electromagnetic energy at higher frequencies. For this reason, the possibility to implement TM-, TE-, or hybrid-polarized BB launchers at millimeter and submillimeter waves is investigated in this work. In particular, three resonant BB launchers working at central frequency of 300 GHz are designed with different polarizations. Full-wave simulations of the proposed devices are in excellent agreement with those theoretically predicted by a rigorous, effective, and well-documented leaky-wave approach. Therefore, this work can be considered as a starting point for the …