Active radiating butterfly antenna

This paper proposes an active radiating antenna with a butterfly shaped resonator, and describes its configuration and experimental results. The measured maximum EIRP (equivalent isotropic radiated power) was 384.170 mW when the input DC power (P/sub DC/) was 187.308 mW. By arraying two antennas, injection locking though mutual coupling was accomplished and a power combining efficiency of 6 dBm up was achieved.