16-10-2010, 07:37 PM
GSM Logical Channels.ppt (Size: 591 KB / Downloads: 97)
GSM.ppt (Size: 950.5 KB / Downloads: 98)
GSM Traffic Channel
Traffic Channels carries Speech and data.
Types of traffic channels :
Full Rate, EFR and Half rate
Full rate
TCH/FS: Speech (13 kbit/s net, 22.8 kbit/s gross)
TCH/EFR: Speech (12.2 kbit/s net, 22.8 kbit/s gross)
TCH/F9.6: 9.6 kbit/s – data
TCH/F4.8: 4.8 kbit/s – data
TCH/F2.4 2.4 kbit/s – data
Half rate
TCH/HS: speech (6.5 kbit/s net, 11.4 kbit/s gross)
TCH/H4.8 4.8 kbit/s – data
TCH/H2.4 2.4 kbit/s – data
Control channel groups(Contd)
BCCH Group: DL only ---- every 30 secs,Continually broadcasts MS’s present cell information, surrounding cells information, information including base station identity, frequency allocations, and frequency-hopping sequences.
SCH:Frame Synchronization
FCCH:Carrier synchronization (Frequency locking)
CCCH:UL and DL.—call origination and call paging
RACH:MS uses to access the network for call setup or responds to a page.
AGCH:used to allocate an SDCCH to a mobile for signalling(in order to obtain a dedicated channel), following a request on RACH
PCH:Used to alert the mobile of an incoming call.
DCCH:UL and DL---for call setup an validation.
SDCCH:carries data to and from MS during call setup and validation.
SACCH:Link measurement and power control messages.
FACCH:to carry event type messages like handovers. used during call establishment.
GLOBAL SYSTEM
FOR
MOBILE COMMUNICATION
Guided by:-
Satya Ranjan Biswal
Presented by:-
Suvendu Kumar Pani
Regd no. -0701289238
IT