HSUPA (High-Speed Uplink Packet Access) - definition
An upgrade for UMTS/HSDPA networks that increases upload data speeds up to 5.76 Mbps. HSUPA together with HSDPA are sometimes referred to as HSPA.
The standard is backwards compatible with UMTS and HSDPA and will work with devices supporting only those standards.
HSUPA only handles the uplink while the downlink is handled by a related technology called HSDPA.