GSM logosi
**GSM** (*Global System for Mobile Communications* - Mobil Axborot Almashinuvining Global Tarmog'i, eski nomi *Groupe Spécial Mobile*) - mobil telefonlar uchun hizmat ko'rsatadigan dunyodagi eng mashxur standart (2007 yil ma'lumotlari).

Ma'lumot
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GSM standartidan dunyoning 212 mamlakat va yerlarida, 2 milliarddan ortiq kishi foydalanishadi. Standartining keng tarqalganligi Mobil Tarmoq Operatorlari orasida Halqaro rouming (Roaming) hizmatini keng joriy qilish bilan birgalikda, foydalanuvchilar uchun shaxsiy mobil telefonlarini boshqa mamlakatlarda ishlatish imkonini beradi.
GSM tarmog'ida Identifikatsiyalanish (Identification) SIM modul orqali amalga oshiriladi. 
GSM identifikatsiya jarayoni uchun A3 va(yoki) A8 algoritmidan, ovoz va boshqa axborotlarni uzatishda A5 (keyinchalik A5/1, A5/2 ishlab chiqilgan) algoritmidan foydalanadi. GSM mobil tarmoq standartlarining 2-chi avlodi (Second Generation-2G) hisoblanadi. GSM standarti 850 MHz, 900 MHz, 1800 MHz, 1900 MHz chastotali diapazonlarda hizmat ko'rsatadi. 2ta chastotali diapazonda ishlovchi telefon apparatlar dual-band, 3 va 4 chastotali diapazonda ishlovchi telefonlar tegishli ravishda tri-band va quad-band telefonlar deb ataladi. Kup operatorlar hizmatlarini 900Mhz va 1800 MHz diapazonida amalga oshirishadi. 900 MHz diapozonda, uplink y'ani axborot uzatish uchun 890MHzdan 915MHzgacha bulgan 124ta tashuvchi chastotasi bulgan 25MHzli diapozondan foydalaniladi. Downlink y'ani axborot qabul uchun 935MHzdan 960MHzgacha bo'lgan diapazon qo'llaniladi. 
GSM Mobil Qurilma MQ (Mobile Equipment) va Asosiy Stansiya AS (Base Station)dan iborat. Mobil qurilma o'z navbatida mobil telefon apparati va SIM (oddiy xalq tilida sim-karta)dan iborat.
GSM ning kamchiligi Mobil Qurilmaning Asosiy Stansiyaga shubxasiz ishonuvchanligidir. Ya'ni Stansiya

| * k
* m
* t
Mobil tarmoq standartlari |
| --- |
| 0G (radiotelefonlar) | 
* MTS
* MTA
\* MTB
\* MTC
\* MTD
* IMTS
* AMTS
* OLT
* Autoradiopuhelin
* B-Netz

 |
| 1G | 

|  |  |
| --- | --- |
| AMPS oilasi | 
* AMPS (TIA/EIA/IS-3, ANSI/TIA/EIA-553)
* N-AMPS (TIA/EIA/IS-91)
* TACS
* ETACS

 |
| Boshqalar | 
* NMT
* C-450
* Hicap
* Mobitex
* DataTAC

 |

 |
| 2G | 

|  |  |
| --- | --- |
| GSM/3GPP oilasi | 
* GSM
* CSD

 |
| 3GPP2 oilasi | 
* cdmaOne (TIA/EIA/IS-95 and ANSI-J-STD 008)

 |
| AMPS oilasi | 
* D-AMPS (IS-54 and IS-136)

 |
| Boshqalar | 
* CDPD
* iDEN
* PDC
* PHS

 |

 |
| 2G oraliq(2.5G, 2.75G) | 

|  |  |
| --- | --- |
| GSM/3GPP oilasi | 
* HSCSD
* GPRS
* EDGE/EGPRS (UWC-136)

 |
| 3GPP2 oilasi | 
* CDMA2000 1X (TIA/EIA/IS-2000)
* 1X Advanced

 |
| Boshqalar | 
* WiDEN

 |

 |
| 3G (IMT-2000) | 

|  |  |
| --- | --- |
| 3GPP oilasi | 
* UMTS
	+ UTRA-FDD / W-CDMA
	+ UTRA-TDD LCR / TD-SCDMA
	+ UTRA-TDD HCR / TD-CDMA

 |
| 3GPP2 oilasi | 
* CDMA2000 1xEV-DO Release 0 (TIA/IS-856)

 |

 |
| 3G oraliq(3.5G, 3.75G, 3.9G) | 

|  |  |
| --- | --- |
| 3GPP oilasi | 
* HSPA
	+ HSDPA
	+ HSUPA
* HSPA+
* LTE (E-UTRA)

 |
| 3GPP2 oilasi | 
* CDMA2000 1xEV-DO Revision A (TIA/EIA/IS-856-A)
* EV-DO Revision B (TIA/EIA/IS-856-B)
* DO Advanced

 |
| IEEE oilasi | 
* Mobile WiMAX
	+ IEEE 802.16e
* Flash-OFDM
* iBurst
	+ IEEE 802.20

 |

 |
| 4G(IMT Advanced) | 

|  |  |
| --- | --- |
| 3GPP oilasi | 
* LTE Advanced (E-UTRA)

 |
| IEEE oilasi | 
* WiMAX (IEEE 802.16m)

 |

 |
| 5G | 

|  |
| --- |
| 
* conceptual (currently under formal research & development)

 |

 |
| Tavsiya etilgan maqolalar | 
* Mobil tarmoqlar
* Mobil telefoniya
* Tarixi
* Standartlar roʻyxati
* Comparison of standards
* Channel access methods
* Spectral efficiency comparison table
* Cellular frequencies
* GSM frequency bands
* UMTS frequency bands
* Mobile broadband
* NGMN Alliance
* MIMO

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