High-Speed Uplink Packet Access

High-Speed Uplink Packet Access (HSUPA) is a 3G mobile telephony protocol in the HSPA family with up-link speeds up to 5.76 Mbit/s. The name HSUPA was created by Nokia. The official 3GPP name for 'HSUPA' is Enhanced Uplink (EUL).

The specifications for HSUPA are included in Universal Mobile Telecommunications System Release 6 standard published by 3GPP. – "The technical purpose of the Enhanced Uplink feature is to improve the performance of uplink dedicated transport channels, i.e. to increase capacity and throughput and reduce delay."

Description

HSUPA uses an uplink enhanced dedicated channel (E-DCH) on which it employs link adaptation methods similar to those employed by High-Speed Downlink Packet Access HSDPA, namely:

Similarly to HSDPA, HSUPA uses a packet scheduler, but it operates on a request-grant principle where the UEs request a permission to send data and the scheduler decides when and how many UEs will be allowed to do so. A request for transmission contains data about the state of the transmission buffer and the queue at the UE and its available power margin. However, unlike HSDPA, uplink transmissions are not orthogonal to each other.

High Speed Packet Access

High Speed Packet Access (HSPA) is an amalgamation of two mobile telephony 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 utilizing the WCDMA protocols. A further improved 3GPP standard, Evolved HSPA (also known as HSPA+), was released late in 2008 with subsequent worldwide adoption beginning in 2010. 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.

Overview

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. It 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.

High Speed Downlink Packet Access (HSDPA)