1xEVDO

1xEVDO, short for 1x Evolution Data Optimized, is a 3G wireless data standard used on CDMA2000 networks. It was designed to deliver higher-speed data services over existing CDMA2000 infrastructure, complementing voice and lower-speed data carried by 1xRTT. The technology was developed by Qualcomm and implemented by many CDMA carriers around the world during the 2000s.

The 1xEVDO air interface employs CDMA techniques to provide dedicated high-speed downlink and uplink channels for IP data. It evolved through several releases, each improving throughput and efficiency. Rev 0 offered up to modest peak downlink speeds (historically around 2.4 Mbps) with limited uplink performance. Rev A significantly increased both directions, delivering higher downlink and improved uplink rates. Rev B further expanded capabilities by adding higher peak rates and multi-carrier/MIMO options to boost overall throughput.

In practice, 1xEVDO typically served mobile broadband data traffic, enabling applications such as web browsing, email, and multimedia streaming. It is distinct from 1xRTT, the voice-oriented CDMA2000 air interface, though networks often shared the same core infrastructure. Quality of Service and session management were provided to support IP data traffic over the wireless link.

Deployment and lifecycle: 1xEVDO saw widespread adoption on CDMA networks in North America, Asia, and elsewhere before being largely superseded by newer technologies such as LTE and, more recently, 5G. Some networks retain 1xEVDO for legacy coverage or backward compatibility, while new devices typically support multiple access technologies for broader interoperability.

See also: CDMA2000, 3G wireless technologies, LTE, and 5G.