A portable internet service (PIS), which is referred to as a 3.5-generation mobile communication, is a next generation wireless data communication service that combines advantages of a wireless internet service (3-generation mobile communication) based on a W-CDMA (wideband-code division multiple access) and a CDMA and advantages of a ultra high speed internet service through a wire net.
Differently from a conventional wireless internet service, a portable internet service of an orthogonal frequency division multiple access (OFDMA) type uses a transmission band of total 100 MHz among a frequency band of 1.9 GHz to 3.0 GHz and a data over 1 Mbps is transmitted even when a user moves with a high speed, for example, 60 km/h.) Accordingly, a portable internet service can satisfy user's requests for high mobility and high speed. In addition, a real-time multimedia data transmission and a simultaneous diverse service are provided to cause a ripple effect to information and communication industries.
FIG. 1 is a schematic view showing a portable internet network of the related art. As shown in FIG. 1, a portable internet network includes a portable subscriber station (PSS) 140, a radio access station (RAS) 130 connected to the PSS 140 through a wireless channel and an access control router (ACR) 120 controlling operation of the RAS 130 and connecting the RAS 130 and an edge router of a subscriber network 110.
The portable internet network provides a portable internet service to the PSS 140 by processing a call connection, a certification and a handover in response to a call from the PSS 140. All or a portion of the call processing may be performed in the RAS 130.
FIG. 2 is a block diagram showing an inner structure of a radio access station of the related art. In FIG. 2, a radio access station (RAS) 130 is connected to an access control router (ACR) 120, and includes a management processor 210 and a plurality of channel cards 220. The management processor 210 controls the call processing of the portable internet and manages all units in the RAS 130, and the plurality of channel cards 220 are provided for securing a wireless communication channel with the PSS 140 (of FIG. 1)