ETSI - TS 148 004
Digital cellular telecommunications system (Phase 2+) (GSM); Base Station System - Mobile-services Switching Centre (BSS - MSC) interface; Layer 1 specification
|Publication Date:||1 July 2018|
The present document defines the structure of the physical layer (layer 1) of the BSS-MSC interface for supporting traffic channels. Use of the physical layer for supporting Signalling System No.7 signalling links is covered in Technical Specification 3GPP TS 48.006.
The physical layer is the lowest layer in the OSI Reference Model and it supports all functions required for transmission of bit streams on the physical medium.
For the present document only digital transmission will be considered, the use of analogue transmission is a national concern.