Download - Gsm overview
GSM OVERVIEW
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MSC
BTS
BSC
BTS PSTN
BTSISDN
SS#7MS
MS
MS
MS
MS
MS
Mobile Station
Base Transceiver
Station
Base Station
Controller
Mobile Service
Switching Center
Visitor Location Register
Home Location Register
Authentication
Center
Equipment Identity Register
GMSCUser
HLR
MSCVLRDirectory
NumberRoutingNumber
RoutingNumber
DirectoryNumber
GMSC handling of a domestic call
GMSC
ÑÒNH NGHÓA CAÙC SOÁ VAØ NHAÄN DAÏNG TRONG HEÄ THOÁNG GSM Soá ISDN cuûa traïm di ñoäng MSISDN
MSISDN = CC+ NDC+ SN
Soá löu ñoäng cuûa maùy di ñoäng MSRN(Mobile Station Roaming Number).
MSRN = CC + NDC + SN
Nhaän daïng thueâ bao di ñoäng quoác teá IMSI (International Mobile Subscriber identity)
IMSI = MCC + MNC + MSIN.
Nhaän daïng thueâ bao di ñoäng taïm thôøi TMSI (Temporary Mobile Subscriber Identity)
Nhaän daïng thieát bò cuûa traïm di ñoäng quoác teá IMEI (International Mobile Equipment Identity)
IMEI = TAC + FAC + SNR + SP
Nhaän daïng vuøng ñònh vò LAI (Location Area Identity)
LAI = MCC + MNC + LAC
Nhaän daïng oâ toaøn caàu (CGI) (Cell Global Identity)
CGI = MCC + MNC + LAC + CI
Maõ nhaän daïng traïm goác (BSIC) (Base Station Identity Code)
BSIC = NCC + BCC.
Authentication & Encryption
Authentication & Encryption
Radio S
ubsystem
RPE-LTPencoder
RPE-LTPdecoder
13 bit uniform to 8 bit A-Law
8 bit A-Law to 13 bit uniform
MS
C
PSTN/
ISDN
104 kbps13 kbps
8000 samples/s13-bit uniform
code
Analoguespeech
8000 samples/s13-bit uniform
code
8000 samples/s8-bit A-Law
ITU-T G.711, G.712,G.713, G.714
RPE-LTPencoder
RPE-LTPdecoder
13 bit uniform to Analogue
O/P
Analogue to 13 bit uniform
I/P
104 kbps 64 kbps13 kbps
System Description
Radio Access & Demod
GMSK
De-Interleaving
Forward Error
CodingInterleaving
Radio Access & ModGMSK
InterleavingForward
Error Coding
Error Correction
Radio Access & ModGMSK
Error Correction
De-Interleaving
Radio Access & Demod
GMSK
Dup Dup
Encoded speech456 bits/frame 20ms
Encoded speech456 bits/frame 20ms
22.8kbps 22.8kbps13 kbps 13 kbps
System Description
Signalling in GSM network
OAM
LAPD
BTS
MTP2
SCCP
MTP3
LAPD
OAM
RR
DTAP
BSSMAP
BSSAP
BSC
MTP1
MTP3
MTP2
SCCP
MTP2
MTP3
SCCP
BSSAPDTAP/
BSSMAP
TCAP
MM
CM MAP
NSS
RR
MM
CM
MS
UmInterface
A bisInterface
AInterface
GSM Specification
Access methodAccess method TDMA/FDMATDMA/FDMA
Frequency band (MS to BS)Frequency band (MS to BS) 890 - 915 MHz890 - 915 MHz
Frequency band (BS to MS)Frequency band (BS to MS) 935 - 960 MHz935 - 960 MHz
Channel bandwidthChannel bandwidth 200 kHz200 kHz
ModulationModulation GMSKGMSK
Bit rateBit rate 270.833 kbps270.833 kbps
FilterFilter BT = 0.3 (Gaussian)BT = 0.3 (Gaussian)
Voice channel codingVoice channel coding RPE-LPC Convolutional 13 kbpsRPE-LPC Convolutional 13 kbps
Frequency HoppingFrequency Hopping Slow hopping (217 hops/s)Slow hopping (217 hops/s)
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