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Cellular is the generic name for the service used by Cell phones. It is often identified with devices that use this service for data only. See cellular network and WWAN.


[edit] Overview

A cellular service is a specific capability of smartphones and is typically charged separately from the minutes used for voice. The charge is based on the amount of data transferred to or from the device. This charge can amount to more than the voice charges and includes such things as web browsing, text messaging, download or uploading pictures, and any other activity other than voice service and caller-ID. Cellular capabilities include GPS support and the ability to assist in obtaining a rapid GPS lock. This is called A-GPS (assisted GPS). In the absence of a GPS signal the cell tower's location itself can be used to provide an approximate location.

Cellular networks are generally referred to by a more specific name like 3G network or LTE. It may also be referred to by its implementation like CDMA, GSM/EDGE, or UMTS.

[edit] The G's

Cellular technology progress is measured in G's (generations). Here is a breakdown:

  • 1G - analog
  • 2G - digital technologies, such as CDMA, GSM, and TDMA, were the first generation of digital cellular.
  • 3G technologies, such as EVDO, HSPA, and UMTS, brought speeds from 200kbps to a few megabits per second. They must meet IMT-2000 technical standards. A system must provide peak data rates of at least 144 kbit/s.[4] However, many services advertised as 3G provide higher speed than the minimum.
  • 4G technologies, such as WiMAX and LTE, were the next incompatible leap forward, and they are now scaling up to hundreds of megabits and even gigabit-level speeds. 4G system does not support traditional circuit-switched telephony service, but instead relies on all-Internet Protocol (IP) based communication such as IP telephony. The spread spectrum radio technology used in 3G systems is abandoned in all 4G candidate systems and replaced by OFDMA multi-carrier transmission and other frequency-domain equalization (FDE) schemes
  • 5G brings three new aspects to the table: greater speed (to move more data), lower latency (to be more responsive), and the ability to connect a lot more devices at once (for sensors and smart devices). You could even turn a router into a cell tower.

[edit] For more information

  • See wikipedia 3G for more information on 3G
  • See wikipedia 4G for more information on 4G
  • See wikipedia 5G for more information on 5G, Apple is releasing all iPhones and iPads with optional phone service with 5th Generation products in 2022.

[edit] Frequencies

  • UMTS/HSDPA/HSUPA/HSPA+ - 850, 900, 1900, 2100 MHz
  • GSM/EDGE - 850, 900, 1800, 1900 MHz
  • CDMA EV-DO Rev A - 800, 1900 MHz, Rev B also 2100 MHz
  • LTE - Bands 4,17 or 1,3,5 and perhaps 13, 25 with speeds up to 1.2Gbps
  • 5G-NR - All bands, low and high, encoding called OFDM which is similar to LTE
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