Although many NO decomposition systems have been developed using plasmas such as dielectric barrier discharges (DBDs), corona discharges, surface discharges, glow discharges, and microwave discharges, the present system is unique on the viewpoint of the use of an intermittent one-cycle sinusoidal power source to generate DBD plasma. There are several features of the system: (1) easy control of the electric power consumed in the DBD plasma, and (2) DBD-plasma generation used only for the production of ammonia radicals. The system employs a radical injection system, where the radicals are produced in a separate discharge chamber, called radical injector, from NO flow field. This enables an efficient production of ammonia radicals being appropriate for DeNOx. It is shown from the temperature dependence of NO removal (DeNOx) characteristics that the present system is a low-temperature DeNOx system compared to a conventional thermal DeNOx system, and NO decomposition is performed over a wide range of gas temperature containing NO. Surveying parametric characteristics of DeNOx, the energy efficiency is improved by a factor of 30% compared to the previously obtained result. (c) 2006 Elsevier B.V. All rights reserved.