In this study, a design, simulation, fabrication, and measurement of the TEM‐TE11 mode converter antenna (MCA) like a pelican beak are investigated. The working frequency of the pelican beak‐shaped MCA (PBMCA) is the frequency in the range of 3.9–4.6 GHz (700 MHz bandwidth). Due to increasing the antenna cross‐section, the probability of the electrical breakdown dramatically reduces. Electrical breakdown may occur at very high power outputs of the electromagnetic sources. The power‐handling capacity of the PBMCA is 829 MW, at the centre frequency. The antenna is simulated and measured at three frequencies. The simulation results are a good agreement with the measurement results.