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Cellular network standards and generation timeline. This is a comparison of standards of wireless networking technologies for devices such as mobile phones.A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1979 and the early to mid-1980s.
GSM, D-AMPS, PDC, iDEN, and PHS are examples of TDMA cellular systems. In the GSM system, the synchronization of the mobile phones is achieved by sending timing advance commands from the base station which instruct the mobile phone to transmit earlier and by how much. This compensates for the speed-of-light propagation delay.
High Speed Downlink Packet Access (HSDPA) is an enhanced 3G (third-generation) mobile communications protocol in the High-Speed Packet Access (HSPA) family. HSDPA is also known as 3.5G and 3G+ . It allows networks based on the Universal Mobile Telecommunications System (UMTS) to have higher data speeds and capacity.
A CSD call functions in a very similar way to a normal voice call in a GSM network. A single dedicated radio time slot is allocated between the phone and the base station . A dedicated "sub-time slot" (16 kbit/s) is allocated from the base station to the transcoder , and finally, another time slot (64 kbit/s) is allocated from the transcoder to ...
Typical 2G standards include GSM and IS-95 with extensions via GPRS, EDGE and 1xRTT, providing Internet access to users of originally voice centric 2G networks. Both EDGE and 1xRTT are 3G standards, as defined by the ITU , but are usually marketed as 2.9G due to their comparatively low speeds and high delays when compared to true 3G technologies.
GSM networks operate in a number of different carrier frequency ranges (separated into GSM frequency ranges for 2G and UMTS frequency bands for 3G), with most 2G GSM networks operating in the 900 MHz or 1800 MHz bands. Where these bands were already allocated, the 850 MHz and 1900 MHz bands were used instead (for example in Canada and the ...
Competitors include Xiaomi and Nokia. 6G is expected to offer faster speeds than 5G but with a shorter range. The IEEE recommends the use of frequencies ranging from 100 GHz to 3 THz, as these frequencies are relatively unused and would allow for exploration of new frequency bands. [8] The methods of deployment of cellular networks is undetermined.
For example, one version of the Nokia 6340i GAIT phone sold in North America can operate on GSM-1900, GSM-850 and legacy TDMA-1900, TDMA-800, and AMPS-800, making it both multi-mode and multi-band. As a more recent example the Apple iPhone 5 and iPhone 4S support quad-band GSM at 850/900/1800/1900 MHz, quad-band UMTS/HSDPA/HSUPA at 850/900/1900 ...