ts to the uplink data speed are being standardized in the 3GPP Release 6 specification. HSUPA is expected to use an uplink Enhanced Dedicated Channel (E-DCH) on which it will employ link adaptation methods similar to those employed by HSDPA: shorter transmission time interval (TTI), enabling faster link adaptation, and HARQ with incremental redundancy, making retransmission more effective. TTI is a parameter in many digital telecom networks related to encapsula- tion of data from higher layers into frames for transmission on the radio link layer. Link adaptation, a term used in wireless communications, describes the adaptation of various parameters, such as modulation, coding, signal, and protocol, to radio link conditions. The key is that the link adaptation process is dynamic and the parameters change as the radio link conditions change. In HSDPA, for example, this can take place every 2 milliseconds. The HSUPA standard enables users to transmit data upstream at a speed of 5.8 3Mbps. As this standard appears commercially, mobile users will be able to 3G: Moving Toward Broadband Wireless exchange and access data and multimedia much more efficiently and enjoyably. HSUPA technology is expected to be introduced in 2007. Some consider HSUPA to be a 3.75G technology. Jointly, downlink and uplink enhancements are referred to as High-Speed Packet Access (HSPA) services. Increased downlink and uplink speeds will further enhance user experiences and increase the use of applications and activities, espe- cially where data is shared between users (e.g., with interactive multiplayer games). HSOPA HSDPA is just beginning to be deployed, and HSUPA isn't here yet, but vendors are already contemplating the next step beyond those technologies, HSOPA. Because it incorporates OFDM and MIMO, HSOPA promises to offer a 40Mbps download speed. Besides faster speeds, HSOPA is expected to dramatically reduce costs because OFDM allows more capacity with a given amount of spec- trum. If HSOPA moves forward in the standards procedure, it is