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1xEV-DO Revision A
CDMA2000 1xEV-DO Revision A (Rev. A) (TIA-856-A) is an evolution of 1xEV-DO Rel. 0 that increases the peak data rate on the reverse and forward links to support a wide-variety of symmetric, delay-sensitive, real-time, and concurrent voice over IP (VoIP) and advanced broadband data applications. It also incorporates Orthogonal Frequency Division Multiplexing (OFDM) technology to enable multimedia broadcast and multicasting services (MBMS) or one-to-many content delivery.


Rev. Aís more symmetric uplink speeds enable users to send large files, email with attachments, high resolution photographs and personal videos from their mobile devices. With its low network latency, user and service tiering with Quality of Service (QoS) and IP-based broadband architecture, Rev. A is able to support time-sensitive applications, such as Voice over IP (VoIP), Push-to-Talk (PTT) and video telephony. Rev. A was launched in October 2006, and it is the most advanced all-IP wide area network broadband technology commercially available today.

Key features of Rev. A include:

  • Advanced Broadband Data: Supports peak data rates of up to 3.1 Mbps in the forward link and 1.8 Mbps in the reverse link within a 1.25 MHz FDD radio channel. In commercial networks, Rev. A achieves an average data throughput on loaded networks of 600-1400 kbps in the forward link and 500-800 kbps in the reverse link. These average rates are higher in partially loaded networks, with some carriers reporting over 2 Mbps average forward link rates. Using SIMO with equalizers in the forward link, and full interference cancellation and 4-way transceiver diversity in the reverse link, the average data throughput of EV-DO Rev. A networks can reach up to 1400-1700 kbps in the forward link and 970-2000 kbps in the reverse link.
  • Higher Spectral Efficiency: Rev. Aís increased rate quantization on both the forward and reverse links enables a more efficient use of the air link resources, better network utilization and a lower cost of delivery. It supports 1.2 times EV-DO Rel. 0ís forward link sector capacity and 3.4 times its reverse link sector capacity, achieving up to 0.768 bit/sec/MHz and 0.300 bit/sec/MHz in the forward and reverse links respectively over a 5 MHz channel.
  • Increased Capacity: On both the forward and reverse link, Rev A. allows operators to support more users and it improves the cost of delivering IP-based voice, data and multimedia services
  • Symmetry: By increasing uplink speeds, Rev. A is the first commercially available wireless technology to deliver a true synchronic broadband experience. Symmetry is important for applications where users send packets of data as often as they receive them, such as receiving and sending email with attachments.
  • Low Average Latency: Below 50 msec node-to-node ping, RTT - making it ideal for delay-sensitive applications
  • Advanced Quality of Service (QoS): Supports the prioritization and delivery of individual packets based on the type of application or user profile. These mechanisms ensure a consistent, high-quality user experience.
  • All-IP: Internet Protocol (IP) is the foundation for all CDMA2000 radio access networks. Like EV-DO Rel. 0, all-IP Rev. A networks provide operators service flexibility and higher bandwidth efficiencies, which translate into greater control and significant cost savings.
  • Advanced Services: Enables the enhanced performance of real-time broadband, symmetric data link, and delay sensitive services such as VoIP, push-to-talk (PTT), push-to-media (PTM), video conferencing, multicasting, see what I see (SWIS), and rich 3D gaming with multiple players
  • Backwards compatibility: Supports existing Rel. 0 applications and devices. This inherent backwards compatibility preserves an operatorís previous network investments. Rev. A is also backwards compatible with CDMA2000 1X and cdmaOne systems.