HSPA

High-Speed Packet Access

Parity between DSL-type broadband speeds and mobile broadband moved a step closer with HSDPA delivering up to 14Mbps in the downlink and HSUPA returning 5.8Mbps in the uplink.

Specifications for HSPA are included in Release 5 (Downlink) and Release 6 (Uplink) of 3GPP specifications.

HSPA improvements in UMTS spectrum efficiency are achieved through:

• New modulation (16QAM) techniques
• Reduced radio frame lengths
• New functionalities within radio networks (including re-transmissions between NodeB and the Radio Network Controller)

Consequently, throughput is increased and latency is reduced (down to 100ms and 50ms for HSDPA and HSUPA respectively).

By the end of 2007, there were 166 commercial HSDPA networks in 75 countries with a further 38 networks committed to deployment.

The first commercial launch of HSUPA was in early 2007 and 24 networks had launched by the end of the year. According to the Global mobile Suppliers Association (GSA); over 45 networks have launched, are testing or plan to deploy HSUPA.

HSPA+ introduces New functionalities

An evolution of HSPA was specified resulting from studies in Release 7 which added multiple input/ multiple output (MIMO) antenna capability and 16QAM (Uplink)/ 64QAM (Downlink) modulation.

Coupled with improvements in the radio access network for continuous packet connectivity, HSPA+ will allow Uplink speeds of 11Mbps and Downlink speeds of 42Mbps within the Release 8 time frame.

The 25 series of the 3GPP specifications contain the major HSPA work on Uplink and Downlink access;

Frozen in Release 5, HSPA work is largely covered by the Radio Access Network (RAN) group of 3GPP

Dual-Cell HSPA

Dual cell or Dual carrier HSPA was defined in 3GPP Release 8, specifying carrier aggregation for increased spectrum efficiency and load balancing across the carriers.

The 3GPP study item was completed in June 2008 as TR 25.825.

According to Wikipedia, DC HSPA delivers the following;

• Release 7, MIMO deployments can benefit from the DC-HSDPA functionality as defined in Release 8.
• Release 8, DC-HSPDA operates on adjacent carriers
• Release 9, paired cells can operate on two different frequency bands, possible to use DC-HSDPA in combination with MIMO.