Miniaturized antipodal tapered slot antenna with lower frequency band extension characteristic

An antipodal tapered slot antenna (ATSA) is miniaturized by extending the lower operating frequency range using spidron‐shaped slots and additional impedance‐matching stubs at the tapered radiator. Simulation and measurement results show that the electrical size of the antenna, or the lowest matching frequency, is reduced by 56.4% when compared to a conventional ATSA with the same physical dimensions. The realized gain is also improved in the newly matched low‐end operating frequency.