The present document gives an overview of the tasks undertaken by a GMR-1 Mobile Earth Station (MES) when in idle mode, that is, switched on but not having a dedicated channel allocated, e.g. not making or receiving a call. It also describes relevant network functions. The idle mode functions are also performed by a MES as long as no dedicated channel is allocated to the MES.

The present document specifies the idle mode operation. Further details are given in TS 101 376-4-8 [4] and TS 101 376-5-6 [7].

Clause 4 of the present document gives a general description of the idle mode process. Clause 5 outlines the main requirements and technical solutions of those requirements. Clause 6 describes the processes used in idle mode.