The base station subsystem (BSS) is an important part of the GSM system.

The base station subsystem mainly includes base station controller (BSCe3), code speed conversion unit (TCUe3), packet control unit (PCU), base station transceiver (BTS), and radio operation and maintenance center (OMC-R).

1, the base station controller (BSCe3) is mainly responsible for managing the base station and  OMC-R connection, and responding to the OMC-R processing. The system is equipped with data and software storage, BSS performance calculation and statistics management, fault detection and processing.

The products with large capacity and expansion capacity :

BSC E3 can manage 1000 TRX, 500 BTS and 600 cells.

High reliability:

All hardware modules are fully redundant (either 1+1 redundancy mechanism or N+P redundancy mechanism), including the PCM interface board.

Economic and efficient operation and maintenance:

The key functions of BSC e3 such as "plug and play" hardware modules, local or remote maintenance terminals, accurate fault detection and reporting make the maintenance of BSC E3 devices more economical and efficient.

The main functions:

The supervision of BTS

The wireless channel allocation

The wireless channel monitoring

The traffic management

The TCUe3 management

The OMC-R link management

The switch process

The request for operation and maintenance of the OMC-R processing

The BSS configuration data and software storage

The BSS performance counter management

The fault monitoring and treatment

2, code speed conversion unit (TCU)

TCUe3 based on Kapsch multi application circuit exchange platform (spectrum). The TCU E3 product hosts 1 or 2 TCU E3 nodes, and is also called "transcoding nodes (TN). TCU E3 should usually be located on the MSC site, and it can be promote and in the same position with BSC.

1) high expansibility

From 1 TN at the capacity of 200 E - 1800 E (EFR call) to 1 TCU e3 cabinets at the capacity of 3600 E. Each TN provides the PCM connectivity of the maximum of 84 E1 or 112 T1.

2) high reliability

TCU can provide switch level availability. The availability of the system is currently 99.999% or has 3 minutes of downtime. All hardware modules are redundant (1+1 or N+1 redundancy mechanism), including the PCM interface board.

3) economic and efficient operation and maintenance with high performance:

The density of TCU is very high, which can obviously reduce the area of high capacity with lower power consumption.

3, packet control unit (PCU)

Product function:

The packet control unit supports PCU function which is responsible by node (PCUSN) and defined by 3GPP. It provides the collaboration between the packet radio interface and the GPRS packet data core network on the base station transceiver (BTS).

It provides collaboration between two interfaces:

1) the Agprs interface between PCUSN and BSCe3 (special interface)

2) the Gb interface between PCUSN and SGSN (open interface)