Tuning Method for a New Electrically Small Antenna With Low $Q$

We theoretically describe and experimentally demonstrate a new class of electrically small spherical antennas with near-minimum radiation Q. The antenna operates by supporting the TM₁₀ spherical mode and minimizing excitation of higher order modes. The antenna compares favorably to existing electrically small antennas and can be easily designed for any frequency or with any electrical size. The antenna can be matched without an external network using methods described in this work. Measurements of two antennas of different electrical sizes are presented to demonstrate the tunability of the structure.