Dielectric barrier discharge（DBD）is an important source for generating transient non-thermal plasma.In this experiment

DBD is produced by repetitive unipolar nanosecond pulses with a rise-time of about 15 ns and a full-width at half-maximum of about 30 ns

and DBD’s voltage

current

and images are measured.The results show that under unipolar HV pulse

DBD current can reach hundreds of amperes and exhibits bipolar feature.According to the calculation

two discharges take place-the primary discharge is generated at the end of rising curve of the nanosecond pulse

and the secondary one is induced at the end of falling curve of the pulse.Realtime power curve of the DBD also has two peaks

and the amplitude can reach to MW magnitude.In addition

the discharge images show two discharge modes-homogeneous discharge and filamentary discharge

and both barrier pattern and repetition rate can affect the transition of the two modes.