Mobil telefonlar bu foydalanuvchi harakatlanayotganda radiochastota aloqasi orqali qo'ng'iroqlarni amalga oshiradigan va qabul qiladigan mobil, uyali yoki oddiygina ko'chma telefon



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1.2. Mobil qurilmalarning ishlab chiqarilish tarixi va rivojlanishi

Mobil telefonlar - bu foydalanuvchi harakatlanayotganda radiochastota aloqasi orqali qo'ng'iroqlarni amalga oshiradigan va qabul qiladigan mobil, uyali yoki oddiygina ko'chma telefon. Radiochastota aloqasi mobil telefon operatorining kommutatsiya tizimlariga ulanishni o'rnatadi, bu umumiy foydalaniladigan telefon tarmog'iga (public switched telephone network - PSTN) ulanishni ta'minlaydi. Zamonaviy uyali telefon xizmatlari uyali aloqa arxitekturasidan foydalanadi va shuning uchun mobil telefonlar uyali telefonlar deb nomlanadi. Telefoniya bilan bir qatorda raqamli mobil telefonlar (2G) matnli xabarlar, MMS, elektron pochta, Internetga kirish, qisqa masofali simsiz aloqa (infraqizil, Bluetooth), biznes dasturlari, video o'yinlar va raqamli fotosuratlar kabi boshqa turli xil xizmatlarni qo'llab-quvvatlaydi. Faqatgina ushbu imkoniyatlarni taqdim etadigan mobil telefonlar xususiyatli telefonlar sifatida tanilgan. Yuqori darajada rivojlangan hisoblash qobiliyatlarini taqdim etadigan mobil telefonlar smartfonlar deb nomlanadi.

Metall-oksid-yarimo'tkazgich (metal-oxide-semiconductor - MOS) ning keng miqyosli integratsiyasi (LSI) texnologiyasi, axborot nazariyasi va uyali aloqa tarmog'ining rivojlanishi arzon mobil aloqaning rivojlanishiga olib keldi. Birinchi qo'l telefoni 1973 yilda John F. Mitchell va Motorola kompaniyalaridan Martin Kuper tomonidan og'irligi 2 kg bo'lgan telefon yordamida amalga oshirilgan. 1979 yilda Nippon Telegraf va Telefon (Nippon Telegraph and Telephone - NTT) Yaponiyada dunyodagi birinchi uyali aloqa tarmog'ini ishga tushirdi. 1983 yilda DynaTAC 8000x savdoda mavjud bo'lgan birinchi qo'l telefoni bo'ldi. 1983 yildan 2014 yilgacha dunyo bo'ylab uyali telefonlarga obunalar yetti milliarddan oshdi. 2016 yilning birinchi choragida dunyodagi eng yaxshi smartfon ishlab chiqaruvchilari Samsung, Apple va Huawei; smartfonlar savdosi mobil telefonlarning umumiy sotilishining 78 foizini tashkil etdi.

Qisqacha tarixi

Motorola kompaniyasining asoschisi Martin Kuper, DynaTAC prototipi modeli bo'yicha 1973 yil 3 aprelda birinchi bo'lib uyali telefon orqali qo'ng'iroqni amalga oshirdi.

Radiotexnikaning dastlabki bosqichlarida qo'lda ishlaydigan mobil radio telefon xizmati ko'zda tutilgan edi. 1917 yilda fin ixtirochisi Erik Tigerstedt "o'ta ingichka uglerodli mikrofon bilan cho'ntak kattalikdagi qatlama telefon" ga patent berdi. Uyali telefonlarning dastlabki ko’rinishlariga kemalar va poezdlardan analog radioaloqa kiritilgan. Haqiqiy ko'chma telefon qurilmalarini yaratish poygasi Ikkinchi Jahon urushidan so'ng boshlandi va ko'plab mamlakatlarda o'zgarishlar yuz berdi. Uyali telefoniya sohasidagi yutuqlar ketma-ket "avlodlar" da kuzatilmoqda, birinchi navbatda zerot avlodlari (0G) xizmatlaridan boshlangan, masalan, Bell Systemning mobil telefon xizmati va uning “avlodlari” - takomillashtirilgan mobil telefon xizmati hisoblanadi. Ushbu 0G tizimlari uyali bo'lmagan, bir vaqtning o'zida bir nechta qo'ng'iroqlarni qo'llab-quvvatlagan va juda qimmat bo'lgan.

Motorola DynaTAC 8000X 1984 yilda u sotuvga qo'yilgan birinchi uyali mobil telefon bo'ldi.

Metall-oksid-yarimo'tkazgich (MOS) keng ko'lamli integratsiya (LSI) texnologiyasi, axborot nazariyasi va uyali aloqa tarmog'ining rivojlanishi arzon mobil aloqa va avtomobil telefoni kabi qurilmalarning rivojlanishiga olib keldi. Birinchi qo'l uyali telefonni 1973 yilda John F. Mitchell va Motorola kompaniyasining asoschisi Martin Kuper 2 kilogramm og'irlikdagi telefon yordamida namoyish etishgan. Birinchi tijorat avtomatlashtirilgan uyali aloqa (1G) analogi Yaponiyada Nippon Telegraph and Telephone tomonidan 1979 yilda ishga tushirilgan. 1981 yilda Daniya, Finlyandiya, Norvegiya va Shvetsiyada bir vaqtning o'zida Nordic Mobile Telephone (NMT) tizimi ishga tushirildi. Keyinchalik boshqa mamlakatlar 1980-yillarning boshidan o'rtalariga qadar ergashdilar. Ushbu birinchi avlod (1G) tizimlari bir vaqtning o'zida ko'proq qo'ng'iroqlarni qo'llab-quvvatlashi mumkin edi, ammo shunga qaramay analog uyali aloqa texnologiyasidan foydalanilgan. 1983 yilda DynaTAC 8000x savdoda mavjud bo'lgan birinchi qo'l telefoni bo'ldi.

Digital cellular networks appeared in the 1990s, enabled by the wide adoption of MOSFET-based RF power amplifiers (power MOSFET and LDMOS) and RF circuits (RF CMOS),[9][10][11] leading to the introduction of digital signal processing in wireless communications.[1] In 1991, the second-generation (2G) digital cellular technology was launched in Finland by Radiolinja on the GSM standard. This sparked competition in the sector as the new operators challenged the incumbent 1G network operators. The GSM standard is a European initiative expressed at the CEPT ("Conférence Européenne des Postes et Telecommunications", European Postal and Telecommunications conference). The Franco-German R&D cooperation demonstrated the technical feasibility, and in 1987 a Memorandum of Understanding was signed between 13 European countries who agreed to launch a commercial service by 1991. The first version of the GSM (=2G) standard had 6,000 pages. The IEEE/RSE awarded to Thomas Haug and Philippe Dupuis the 2018 James Clerk Maxwell medal for their contributions to the first digital mobile telephone standard. [12] In 2018, the GSM was used by over 5 billion people in over 220 countries. The GSM (2G) has evolved into 3G, 4G and 5G.

Raqamli uyali aloqa tarmoqlari 1990-yillarda paydo bo'ldi, bu MOSFET-ga asoslangan chastotali quvvat kuchaytirgichlari (quvvat MOSFET va LDMOS) va chastotali zanjirlarning (RF CMOS) keng qo'llanilishi bilan ta'minlandi, simsiz aloqada ishlash raqamli signalni kiritishga olib keldi. 1991 yilda Finlyandiyada GSM standarti bo'yicha Radiolinia tomonidan ikkinchi avlod (2G) raqamli uyali aloqa texnologiyasi ishga tushirildi va bu sohada raqobatni keltirib chiqardi, chunki yangi operatorlar amaldagi 1G tarmoq operatorlariga qarshi chiqishdi. GSM standarti CEPT ("Conférence Européenne des Postes et Telekommunikatsiya", Evropa pochta va telekommunikatsiya konferentsiyasi) da ifodalangan Evropaning tashabbusi hisoblanadi. Frantsiya-Germaniya ilmiy-tadqiqot sohasidagi hamkorlik texnik imkoniyatlarini namoyish etdi va 1987 yilda Evropaning 13 mamlakati o'rtasida o'zaro anglashuv memorandumi imzolandi va 1991 yilgacha tijorat xizmatini ishga tushirishga rozi bo'ldi. GSM (= 2G) standartining birinchi versiyasi 6000 sahifadan iborat edi. IEEE / RSE birinchi raqamli mobil telefon standartiga qo'shgan hissasi uchun Tomas Xag va Filipp Dupuisga 2018 yilda Jeyms Klerk Maksvell medali topshirildi. 2018 yilda GSMdan 220 dan ortiq mamlakatda 5 milliarddan ortiq kishi foydalangan. GSM (2G) 3G, 4G va 5G ga aylandi.

Personal Handy-phone System mobiles and modems, 1997–2003

The lithium-ion battery, an indispensable energy source for modern mobile phones, [13] was commercialized by Sony and Asahi Kasei in 1991. [14][15] In 2001, the third generation (3G) was launched in Japan by NTT DoCoMo on the WCDMA standard.[16] This was followed by 3.5G, 3G+ or turbo 3G enhancements based on the high-speed packet access (HSPA) family, allowing UMTS networks to have higher data transfer speeds and capacity.

Shaxsiy telefon tizimlari mobil telefonlari va modemlari, 1997-2003

Zamonaviy uyali telefonlar uchun ajralmas energiya manbai bo'lgan litiy-ionli akkumulyator 1991 yilda Sony va Asahi Kasei tomonidan tijoratlashtirildi. [14] [15] 2001 yilda Yaponiyada NTT DoCoMo tomonidan WCDMA standartida uchinchi avlod (3G) ishlab chiqarildi. Buning ortidan UMTS tarmoqlariga ma'lumotlarni uzatish tezligi va imkoniyatlarini oshirishga imkon beradigan, yuqori tezlikda paketli kirish (HSPA) oilasiga asoslangan 3,5G, 3G + yoki turbo 3G-qo'shimchalar kiritildi.

By 2009, it had become clear that, at some point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications, such as streaming media. [17] Consequently, the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3G technologies. The first two commercially available technologies billed as 4G were the WiMAX standard, offered in North America by Sprint, and the LTE standard, first offered in Scandinavia by TeliaSonera.

2009 yilga kelib, bir muncha vaqt 3G tarmoqlari tarmoqli kengligi talab qiladigan dasturlarning o'sishi, masalan, translatsiya ommaviy axborot vositalari bilan zabt etilishi aniq bo'ldi. Binobarin, sanoat ma'lumotlarning optimallashtirilgan to'rtinchi avlod texnologiyalarini qidirishni boshladi va mavjud 3G texnologiyalariga nisbatan tezlikni o'n baravar oshirishni va'da qildi. 4G sifatida taqdim etilgan tijoratda mavjud bo'lgan dastlabki ikkita texnologiya - Shimoliy Amerikada Sprint tomonidan taqdim etilgan WiMAX standarti va birinchi bo'lib TeliaSonera tomonidan Skandinaviyada taqdim etilgan LTE standarti hisoblanadi.

5G is a technology and term used in research papers and projects to denote the next major phase in mobile telecommunication standards beyond the 4G/IMT-Advanced standards. The term 5G is not officially used in any specification or official document yet made public by telecommunication companies or standardization bodies such as 3GPP, WiMAX Forum or ITU-R. New standards beyond 4G are currently being developed by standardization bodies, but they are at this time seen as under the 4G umbrella, not for a new mobile generation.

5G - bu 4G / IMT-Advanced standartlaridan tashqari mobil telekommunikatsiya standartlarining navbatdagi asosiy bosqichini ko'rsatadigan tadqiqot ishlari va loyihalarda qo'llaniladigan texnologiya va atamadir. 5G atamasi hech qanday spetsifikatsiyada yoki rasmiy hujjatda rasmiy ravishda ishlatilmaydi, ammo telekommunikatsiya kompaniyalari yoki 3GPP, WiMAX Forum yoki ITU-R kabi standartlashtirish organlari tomonidan e'lon qilingan. Hozirgi vaqtda standartlashtirish organlari tomonidan 4G dan yuqori bo'lgan yangi standartlar ishlab chiqilmoqda, ammo ular hozirgi vaqtda yangi mobil avlod uchun emas, balki 4G soyaboni ostida ko'rinadi.

Types


Har 100 kishiga to’g’ri keladigan uyali telefonlar

Active mobile broadband subscriptions per 100 inhabitants.[19]

Smartphone

Main article: Smartphone

Smartphones have a number of distinguishing features. The International Telecommunication Union measures those with Internet connection, which it calls Active Mobile-Broadband subscriptions (which includes tablets, etc.). In the developed world, smartphones have now overtaken the usage of earlier mobile systems. However, in the developing world, they account for around 50% of mobile telephony.

Asosiy maqola: Smartfon

Smartfonlar bir qator ajralib turadigan xususiyatlarga ega. Xalqaro elektraloqa ittifoqi Internetga ulanadiganlarni o'lchaydi, uni faol mobil-keng polosali obunalar deb ataydi (planshetlar va boshqalarni o'z ichiga oladi). Rivojlangan dunyoda smartfonlar avvalgi mobil tizimlardan foydalanishni ortda qoldirdi. Biroq, rivojlanayotgan dunyoda ular uyali telefoniyaning 50% ga to'g'ri keladi.

Feature phone

Main article: Feature phone

Feature phone is a term typically used as a retronym to describe mobile phones which are limited in capabilities in contrast to a modern smartphone. Feature phones typically provide voice calling and text messaging functionality, in addition to basic multimedia and Internet capabilities, and other services offered by the user's wireless service provider. A feature phone has additional functions over and above a basic mobile phone which is only capable of voice calling and text messaging. [20][21] Feature phones and basic mobile phones tend to use a proprietary, custom-designed software and user interface. By contrast, smartphones generally use a mobile operating system that often shares common traits across devices.

Asosiy telefon

Asosiy maqola: Badiiy telefon

Xususiy telefon - bu odatda zamonaviy smartfondan farqli o'laroq imkoniyatlari cheklangan mobil telefonlarni ta'riflash uchun retronim sifatida ishlatiladigan atama. Xususiy telefonlar odatda asosiy multimedia va Internet imkoniyatlaridan tashqari, ovozli qo'ng'iroq va matnli xabar almashish funksiyalarini va foydalanuvchining simsiz xizmat ko'rsatuvchi provayderi tomonidan taqdim etiladigan boshqa xizmatlarni taqdim etadi. Xususiy telefon oddiy ovozli telefonda qo'shimcha funktsiyalarga ega, ular faqat ovozli qo'ng'iroqlar va matnli xabarlarni yuborish imkoniyatiga ega. [20] [21] Xususiy telefonlar va asosiy mobil telefonlar xususiy, maxsus ishlab chiqilgan dasturiy ta'minot va foydalanuvchi interfeysidan foydalanishga moyil. Aksincha, smartfonlar odatda mobil qurilmalarda tez-tez uchraydigan xususiyatlarga ega bo'lgan mobil operatsion tizimdan foydalanadilar.

Infrastructure

Main articles: Cellular network and WiFi

Mobile phones communicate with cell towers that are placed to give coverage across a telephone service area, which is divided up into 'cells'. Each cell uses a different set of frequencies from neighboring cells, and will typically be covered by three towers placed at different locations. The cell towers are usually interconnected to each other and the phone network and the internet by wired connections. Due to bandwidth limitations each cell will have a maximum number of cell phones it can handle at once. The cells are therefore sized depending on the expected usage density, and may be much smaller in cities. In that case much lower transmitter powers are used to avoid broadcasting beyond the cell.

Infratuzilma

Asosiy maqolalar: Uyali aloqa tarmog'i va WiFi

Uyali telefonlar "uyalar" ga bo'lingan telefon xizmat ko'rsatish zonasi bo'ylab qamrab olish uchun joylashtirilgan uyali minoralar bilan aloqa qiladi. Har bir hujayra qo'shni katakchalardan turli xil chastotalar to'plamidan foydalanadi va odatda har xil joylarda joylashgan uchta minora bilan qoplanadi. Uyali aloqa minoralari odatda bir-biriga va telefon tarmog'i va Internetga simli ulanishlar bilan bog'langan. Tarmoqli kengligi cheklanganligi sababli, har bir hujayra bir vaqtning o'zida eng ko'p ishlaydigan ko'plab uyali telefonlarga ega bo'ladi. Shuning uchun hujayralar kutilayotgan foydalanish zichligiga qarab kattalashtiriladi va shaharlarda ancha kichik bo'lishi mumkin. Bunday holda, hujayradan tashqarida translyatsiyani oldini olish uchun transmitterning ancha past kuchlaridan foydalaniladi.

In order to handle the high traffic, multiple towers can be set up in the same area (using different frequencies). This can be done permanently or temporarily such as at special events like at the Super Bowl, Taste of Chicago, State Fair, NYC New Year's Eve, hurricane hit cities, etc. where cell phone companies will bring a truck with equipment to host the abnormally high traffic with a portable cell.

Cellular can greatly increase the capacity of simultaneous wireless phone calls. While a phone company for example, has a license to 1,000 frequencies, each cell must use unique frequencies with each call using one of them when communicating. Because cells only slightly overlap, the same frequency can be reused. Example cell one uses frequency 1–500, next door cell uses frequency 501–1,000, next door can reuse frequency 1–500. Cells one and three are not "touching" and do not overlap/communicate so each can reuse the same frequencies.[citation needed]

Yuqori tirbandlikni boshqarish uchun bir xil hududda bir nechta minoralar o'rnatilishi mumkin (turli chastotalar yordamida). Bu doimiy yoki vaqtincha amalga oshirilishi mumkin, masalan Super Bowl, Taste of Chicago, State Fair, NYC Yangi yil arafasida, bo'ronli shaharlarda va hokazo. Bu erda uyali aloqa kompaniyalari g'ayritabiiy tarzda joylashadigan uskunalar bilan yuk mashinasini olib kelishadi. portativ hujayra bilan yuqori trafik.

Uyali aloqa bir vaqtning o'zida simsiz telefon orqali qo'ng'iroq qilish imkoniyatlarini sezilarli darajada oshirishi mumkin. Masalan, telefon shirkati 1000 chastotali litsenziyaga ega bo'lsa-da, har bir uyali aloqa paytida har bir qo'ng'iroq paytida o'ziga xos chastotalardan foydalanishi kerak. Hujayralar ozgina ustma-ust tushganligi sababli, bir xil chastotani qayta ishlatish mumkin. Masalan, birinchi hujayra 1-500 chastotasini ishlatadi, keyingi hujayra 501-1000 chastotasini ishlatadi, keyingi eshik 1-500 chastotasini qayta ishlatishi mumkin. Bir va uchta kataklar "tegmayapti" va bir-birining ustiga chiqmaydi / bog'lanmaydi, shuning uchun har biri bir xil chastotalarni qayta ishlatishi mumkin.

This is even more greatly increased when phone companies implemented digital networks. With digital, one frequency can host multiple simultaneous calls increasing capacity even more.

As a phone moves around, a phone will "hand off" - automatically disconnect and reconnect to the tower of another cell that gives the best reception.

Additionally, short-range Wi-Fi infrastructure is often used by smartphones as much as possible as it offloads traffic from cell networks on to local area networks.

Bu telefon kompaniyalari raqamli tarmoqlarni amalga oshirishda yanada oshdi. Raqamli, bitta chastota bir vaqtning o'zida bir nechta qo'ng'iroqlarni qabul qilish imkoniyatini oshirishi mumkin.

Telefon atrofida harakatlanayotganda, telefon "o'chadi" - avtomatik ravishda o'chiriladi va eng yaxshi qabul qiluvchi boshqa kameraning minorasiga ulanadi.

Bundan tashqari, qisqa masofali Wi-Fi infratuzilmasi ko'pincha smartfonlar tomonidan imkon qadar ko'proq foydalaniladi, chunki u trafikni uyali tarmoqlardan mahalliy tarmoqlarga tushiradi.

Hardware


Main article: Mobile phone features

The common components found on all mobile phones are:

A central processing unit (CPU), the processor of phones. The CPU is a microprocessor fabricated on a metal–oxide–semiconductor (MOS) integrated circuit (IC) chip.

A battery, providing the power source for the phone functions. A modern handset typically uses a lithium-ion battery (LIB), whereas older handsets used nickel–metal hydride (Ni–MH) batteries.

An input mechanism to allow the user to interact with the phone. These are a keypad for feature phones, and touch screens for most smartphones (typically with capacitive sensing).

A display which echoes the user's typing, and displays text messages, contacts, and more. The display is typically either a liquid-crystal display (LCD) or organic light-emitting diode (OLED) display.

Speakers for sound.

Subscriber Identity Module (SIM) cards and Removable User Identity Module (R-UIM) cards.

A hardware notification LED on some phones

Low-end mobile phones are often referred to as feature phones and offer basic telephony. Handsets with more advanced computing ability through the use of native software applications are known as smartphones.

Central processing unit

Mobile phones have central processing units (CPUs), similar to those in computers, but optimised to operate in low power environments.

Mobile CPU performance depends not only on the clock rate (generally given in multiples of hertz)[22] but also the memory hierarchy also greatly affects overall performance. Because of these problems, the performance of mobile phone CPUs is often more appropriately given by scores derived from various standardized tests to measure the real effective performance in commonly used applications.

Display


Main article: Display device

One of the main characteristics of phones is the screen. Depending on the device's type and design, the screen fills most or nearly all of the space on a device's front surface. Many smartphone displays have an aspect ratio of 16:9, but taller aspect ratios became more common in 2017.

Screen sizes are often measured in diagonal inches or millimeters; feature phones generally have screen sizes below 90 millimetres (3.5 in). Phones with screens larger than 130 millimetres (5.2 in) are often called "phablets." Smartphones with screens over 115 millimetres (4.5 in) in size are commonly difficult to use with only a single hand, since most thumbs cannot reach the entire screen surface; they may need to be shifted around in the hand, held in one hand and manipulated by the other, or used in place with both hands. Due to design advances, some modern smartphones with large screen sizes and "edge-to-edge" designs have compact builds that improve their ergonomics, while the shift to taller aspect ratios have resulted in phones that have larger screen sizes whilst maintaining the ergonomics associated with smaller 16:9 displays. [23][24][25]

Liquid-crystal displays are the most common; others are IPS, LED, OLED, and AMOLED displays. Some displays are integrated with pressure-sensitive digitizers, such as those developed by Wacom and Samsung, [26] and Apple's "3D Touch" system.

Sound

In sound, smartphones and feature phones vary little. Some audio-quality enhancing features, such as Voice over LTE and HD Voice, have appeared and are often available on newer smartphones. Sound quality can remain a problem due to the design of the phone, the quality of the cellular network and compression algorithms used in long-distance calls. [27][28] Audio quality can be improved using a VoIP application over WiFi.[29] Cellphones have small speakers so that the user can use a speakerphone feature and talk to a person on the phone without holding it to their ear. The small speakers can also be used to listen to digital audio files of music or speech or watch videos with an audio component, without holding the phone close to the ear.



Battery

The average phone battery lasts 2–3 years at best. Many of the wireless devices use a Lithium-Ion (Li-Ion) battery, which charges 500–2500 times, depending on how users take care of the battery and the charging techniques used. [30] It is only natural for these rechargeable batteries to chemically age, which is why the performance of the battery when used for a year or two will begin to deteriorate. Battery life can be extended by draining it regularly, not overcharging it, and keeping it away from heat. [31][32]

SIM card

Main articles: Subscriber Identity Module and Removable User Identity Module



Typical mobile phone mini-SIM card



Mobile phones require a small microchip called a Subscriber Identity Module or SIM card, in order to function. The SIM card is approximately the size of a small postage stamp and is usually placed underneath the battery in the rear of the unit. The SIM securely stores the service-subscriber key (IMSI) and the Ki used to identify and authenticate the user of the mobile phone. The SIM card allows users to change phones by simply removing the SIM card from one mobile phone and inserting it into another mobile phone or broadband telephony device, provided that this is not prevented by a SIM lock. The first SIM card was made in 1991 by Munich smart card maker Giesecke & Devrient for the Finnish wireless network operator Radiolinja. [citation needed]

A hybrid mobile phone can hold up to four SIM cards, with a phone having an IMEI per SIM Card. SIM and R-UIM cards may be mixed together to allow both GSM and CDMA networks to be accessed. From 2010 onwards, such phones became popular in emerging markets, [33] and this was attributed to the desire to obtain the lowest on-net calling rate.
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