CDMA2000 1xRTT CDMA Protocol

CDMA2000 1xRTT is a third-generation (3G) wireless technology standard developed by the 3rd Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of standards. It is based on Code Division Multiple Access (CDMA) and is backward compatible with the second-generation (2G) cdmaOne (IS-95) technology.

Key Features and Characteristics

  • Spectral Efficiency: CDMA2000 1xRTT uses Direct Sequence Spread Spectrum (DSSS) Multiple Access and Orthogonal Code Channelization to improve spectral efficiency and mitigate interference, thereby increasing system capacity.
  • Data Speeds: It supports packet data speeds of up to 307 kbps in a single 1.25 MHz channel, making it suitable for both voice and data services.
  • Voice-Centric: The technology is primarily voice-centric but also supports packet data services. It includes features like Fast Uplink Power Control, Rake Receivers, and Soft Handoff to ensure seamless service and high spectral efficiency.
  • Compatibility: It is fully downward compatible with cdmaOne (IS-95), making the upgrade path easy and seamless for operators.

History

CDMA2000 1xRTT evolved from the cdmaOne (IS-95) technology, which was the first CDMA standard deployed by wireless service providers. The evolution of CDMA technology can be summarized as follows:

  1. cdmaOne (IS-95): This was the first CDMA standard, introduced in the late 1990s. It provided basic voice transmission capabilities and was widely used in North America and South Korea.
  2. cdma2000 1xRTT (IS-2000): Released in the early 2000s, this standard increased voice service capacity and improved data transmission rates. It supported packet data speeds of up to 153 kbps and was recognized by the International Telecommunications Union (ITU) as an IMT-2000 standard.
  3. 1X Advanced (Rev.E): This is an evolution of CDMA2000 1xRTT, providing up to four times the capacity and 70% more coverage compared to the original 1xRTT. It supports new radio configurations and includes enhanced features like femtocell support and geolocation support.

Deployment and Impact

CDMA2000 1xRTT has been widely deployed globally, particularly in North America and South Korea. It has been used to deliver circuit-switched services such as voice, SMS, and MMS, as well as packet data services. The technology has played a significant role in the transition to 3G networks, offering improved spectral efficiency and higher data transmission rates compared to its predecessors.

In summary, CDMA2000 1xRTT is a critical component of the CDMA2000 family of standards, offering enhanced voice and data services through its advanced CDMA technology. Its backward compatibility with cdmaOne and continuous evolution have made it a cornerstone in the development of 3G wireless networks.