Ultra-wideband standard antenna for transient field measurement of short electromagnetic pulse

The accurate measurement and metrology for the transient field of the short electromagnetic pulse put forward high requirements for the bandwidth, the fidelity, even the size of the receiving antenna. An electrically short dipole antenna serving that purpose is developed in this paper. The dipole geometry is designed and the antenna parameters are calculated by an analytic approach. A particular gap is designed in the middle of the dipole geometry. It ensures that the dipole and the transmission line will be welded together perfectly. Hence the real sensitivity will be identical to the analytic value. In order to eliminate the interferences and maintain a high fidelity, the two-coaxial feeder is used as the antenna´s transmission line. The performances of the antenna are simulated by the FDTD algorithm and tested in a UWB TEM cell. The antenna has a very wide bandwidth of 5.4GHz. By using the two-coaxial transmission line, the interferences feed into the two cables in common mode and will be eliminated effectively by just difference operation of the two outputs. The field waveform restored by the antenna is highly similar to the incident field waveform. The fidelity factors are lager than 0.95. The difference between the test result of the antenna sensitivity and the analytic value is smaller than 5%.