Write short notes on modes in GSM channels

The different modes of GSM channel are as follows

1. Channel mode

2. Dedicated mode

3. Idle mode

1. Channel modes: Because of the precious value of the radio spectrum, individual users cannot have their own TCH at all times.

2. Dedicated mode: Uses TCH during call establishment and uses SACCH to perform location updating in the dedicated mode. TCH and SACCH are dedicated channels for both uplink and downlink channels.

3. Idle mode: During non call activities, the five downlink channels are in the idle mode: FCCH; SCH; BCCH, which is broadcasting regularly; PAGCH and CBCH, which sends one message every 2 s. During idle mode, the mobile station listens to the common downlink channels, and also uses SDCCH (uplink channel) to register a mobile location associated with a particular base station to the network.