scope:

The present document provides the overall description for lower-layer functions of the GEO-Mobile Radio Third Generation Satellite Packet Radio Service (GMR-1 3G) radio interface.

The overall description provides the following information:

• The services offered to higher-layer functions.

• The distribution of required functions into functional groups.

• A definition of the capabilities of each functional group.

• Service primitives for each functional group, including a description of what services and information flows are to be provided.

• A model of operation for information flows within and between the functions.

The present document is applicable to the following GMR-1 3G functional layers:

• Radio Link Control functions.

• Medium Access Control functions.

• Physical Link Control functions.

The present document describes the information transfer and control functions to be used across the GMR-1 3G radio interface for communication between the MES and the Network.

The overall GMR-1 3G logical architecture and the GMR-1 3G functional layers above the Radio Link Control and Medium Access Control layer are the same as GSM/GPRS as described in TS 123 060 [3].

TS 101 376-4-7 [5] contains a description in general terms of the structured functions and procedures of this protocol and the relationship of this protocol with other layers and entities.

TS 101 376-4-8 [6] contains the definition of GMR-1 3G RLC/MAC procedures when operating on the Common Control Channel (CCCH).

TS 101 376-4-12 [7] contains the definition of RLC/MAC functions when operating on a Packet Data Channel (PDCH).

The functional procedures for the Logical Link Control (LLC) layer above the RLC/MAC are the same as GSM/GPRS as described in TS 144 064 [8].

TS 101 376-5-1 [11] and the GMR-1 3G 45-series [12] to [17] to defines the Physical Link layer and Physical RF layer.