Evolution-Data Optimized or Evolution-Data only, abbreviated as EV-DO or EVDO and often EV, is a telecommunications standard for the wireless transmission of data through radio signals, typically for broadband Internet access.
It uses multiplexing techniques such as Code division multiple access (CDMA) as well as Frequency division duplex (FDD) to maximize the amount of data transmitted.
It is standardized by 3rd Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of standards and has been adopted by many mobile phone service providers around the world – particularly those previously employing CDMA networks, as opposed to GSM networks.
There have been several revisions of the standard, named alphabetically starting with the first as Rev. A ("revision A") while the first standard is referred to simply as Rev. 0.
The EV-DO feature of CDMA2000 networks provides access to mobile devices with air interface speeds of up to 2.4 Mbit/s with Rev. 0 and up to 3.1 Mbit/s with Rev. A. High-Speed Downlink Packet Access (HSDPA), a competing technology for Wideband Code Division Multiple Access (W-CDMA), along with the new Qualcomm Rev.
A modems can maintain both circuit switched voice and packet data calls from the same radio; this is not possible with Qualcomm Rev. 0 chipsets. It provides an IP based network.
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