User Manual

BSS C ONFIGURATION AND U SER G UIDE

2. BSS Overview

The base station subsystem (BSS) is responsible for setting

up, maintaining, and terminating the radio connections

towards the mobile station (MS). BSS is a common resource

where the same equipment and frequencies are used for

both packet-switched and circuit-switched traffic. It can

handle GSM 850, 900, 1800, and 1900 bands.

The WorldGSM

™

BSS supports both transmission

distribution mode (TDM) and internet protocol (IP)

interfaces. This facilitates easy integration into the existing

systems of the operators in the GSM architecture.

It also supports logical channels, which are separated into

traffic channels and signaling channels. The traffic channels

are half and full rate traffic channels (TCH) (TCH - HR/FR).

The signaling channels are subdivided into the following

three categories:

• Broadcast channels (BCH)

• Common control channels (CCCH)

• Dedicated control channels (DCCH)

The GSM specification permits only certain channel

combinations of logical channels, which WorldGSM

™

also

supports.

BSS Components

The BSS comprises of nodes and functionality related to the

radio access network within GSM and performs all radio

related functions.

It consists of the following two components: