ZTE Corporation ZXG-BTS2 Manuale Utente

 
ZXG10-BTS (V2.9) Technical Manual 

Confidential and Proprietary Information of ZTE CORPORATION  

the external environment monitoring system, interface of the tower 

amplifier system and the local O&M interface.  

The Abis interface is a communication interface between BTS and BSC. 

The Um interface is the interface between BTS and MS. The B interface is 
actually an extension of the Abis interface. The M interface between BTS 
and the monitoring system of the external environment provides a 

transparent path for the O&M of the ZXG10-BTS (V2.9).The tower 
amplifier system provides the power supply and the alarm interfaces. The 

man-machine interface (MMI) is an interface between the local O&M 
terminal (LMT) and BTS. 

Interfaces 

Abis Interface 

The Abis interface is defined as an interface between BSC and BTS. 

The Abis interface sends the signal from the BSC to the BTS, usually the 

standard E1 signal of PCM 2M.The unbalanced input mode of 75 ohm 
coaxial cable is adopted for it to implement access through the 

transmission equipment digital microwave, fiber transmission (SDH and 
PDH) and satellite link. 

Physically, an E1 interface is adopted as the Abis interface, and it is 
connected with the thin coaxial cable & D-socket.  

Protocols on the Abis interface are hierarchical, and the protocol hierarchy 
of circuit service is shown in Figure 10. The Abis interface does not process 
the packet service protocol, and it is transparent for the packet signaling. 

Abis Interface

BTS

BTSM

LAPD

Sig.L1

BSC

Sig.L2

LAPD

BTSM

RR

 

 

On the Abis interface, the circuit service protocols fall into three layers: