This Standard specifies the radio air interface of the Real Zero Single Sideband Modulation System which is occupied for the communications of business-use services including public services in 400 MHz band and 150 MHz band defined in the Article 57-2-2 of the Ordinance Regulating Radio Equipment.

And, the system corresponds to the classification for standards that the modulation system is the real zero single sideband modulation system and the channel separation is 6.25 kHz.

The narrow band communication system which uses the real zero single sideband modulation system in the private communication networks for the business-use services including the public services consists of the base station equipment and the mobile station equipment, and communicates between the base station and the mobile station, or the mobile station and the mobile station (by way of the base station or directly). Hereafter, the communication from a mobile station to a mobile station means the communication configuration by way of the base station, and the direct communication from a mobile station to a mobile station means the communication configuration not by way of the base station.