Frame diagram of mobile communication system

The mobile communication system is mainly composed of mobile subsystem (MS), base station subsystem (BSS), network subsystem (NSS) and operation support subsystem (OSS).

The base station subsystem (BSS) provides and manages the transmission path between the mobile station system (MS) and the network subsystem (NSS), especially including the wireless interface management between the MS and the functional entities of the mobile communication system. NSS must manage communication services and undertake the task of establishing communication between mobile stations and related public communication networks or with other mobile stations ... MS, BSS and NSS constitute the physical parts of the mobile communication system, while OSS controls and maintains these practical parts.