The following table is derived from table 5.1a of the release 11 of 3GPP TS 25.306 and shows maximum data rates of different device classes and by what combination of features they are achieved. In HSDPA, voice calls are usually prioritized over data transfer.
#Downlink definition update
The upgrade to HSDPA is often just a software update for WCDMA networks. Additional new features include the High Speed Downlink Shared Channels (HS-DSCH), quadrature phase-shift keying, 16- quadrature amplitude modulation, and the High Speed Medium Access protocol (MAC-hs) in base stations. HSDPA is based on shared channel transmission, and its key features are shared channel and multi-code transmission, higher-order modulation, short Transmission Time Interval (TTI), fast link adaptation and scheduling, and fast hybrid automatic repeat request (HARQ). The improvement in speed and latency reduced the cost per bit and enhanced support for high-performance packet data applications. This phase introduced new basic functions and was aimed to achieve peak data rates of 14.0 Mbit/s with significantly reduced latency. The first phase of HSDPA was specified in 3GPP Release 5. Under 3GPP Release 11, even higher speeds of up to 337.5 Mbit/s were possible. Evolved High Speed Packet Access (HSPA+), introduced in 3GPP Release 7, further increased data rates by adding 64QAM modulation, MIMO, and Dual-Carrier HSDPA operation. It was accompanied by an improvement to the uplink that provided a new bearer of 384 kbit/s (the previous maximum bearer was 128 kbit/s). HSDPA also decreases latency, and therefore the round-trip time for applications. It allows networks based on the Universal Mobile Telecommunications System (UMTS) to have higher data speeds and capacity. High Speed Downlink Packet Access ( HSDPA) is an enhanced 3G (third-generation) mobile communications protocol in the High-Speed Packet Access (HSPA) family. High Speed Downlink Packet Access (HSDPA) Ĭellular network standards and generation timeline They also reduced latency and provided up to five times more system capacity in the downlink and up to twice as much system capacity in the uplink compared with original WCDMA protocol. The first HSPA specifications supported increased peak data rates of up to 14 Mbit/s in the downlink and 5.76 Mbit/s in the uplink. The newer standard allows bit rates to reach as high as 337 Mbit/s in the downlink and 34 Mbit/s in the uplink however, these speeds are rarely achieved in practice. A further-improved 3GPP standard called Evolved High Speed Packet Access (also known as HSPA+) was released late in 2008, with subsequent worldwide adoption beginning in 2010. High Speed Packet Access ( HSPA) is an amalgamation of two mobile protocols-High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA)-that extends and improves the performance of existing 3G mobile telecommunication networks using the WCDMA protocols.
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