Generation of powerful, superbroad-band, subnanosecond electromagnetic pulses

The excitation of superbroad-band TEM antennas with a high-voltage subnanosecond modulator permitting a pulse-repetition frequency of up to 100 Hz is experimentally investigated. The modulator consists of a RADAN-303B nanosecond driver and a pulse amplifier based on gas discharges. The instrument generates unipolar and bipolar pulses of tunable length and amplitude. The amplitude and power of the pulses sent to the antenna reach 100 kV and 200 MW. Data are obtained on the stability of the parameters of the subnanosecond modulator pulses. Information is given on the electrical strength of the air insulation in the matching interval between the modulator and the antenna. The superbroad-band pulses emitted are recorded at distances of up to 25 m. The characteristics of the instrument permit the spatial resolution of reflections from conducting objects with a shape-inhomogeneity scale of no more than 25 cm. Emitters with increased directionality in the E or H (E and H) planes based on two (four) TEM antenna supplied with split modulator pulses are investigated. In-phase and antiphase antenna configurations are considered.