Evolved HSPA
Evolved High-Speed Packet Access, or HSPA+, is a technical standard for wireless, broadband telecommunication. HSPA+ enhances the widely used WCDMA (UMTS) based 3G networks with higher speeds for the end user that are comparable to the newer LTE networks. HSPA+ was first defined in the technical standard 3GPP release 7 and expanded further in later releases.
In the United States, it is commonly available under AT&T Mobility and T-Mobile US.
Speeds
HSPA+ provides an evolution of High Speed Packet Access and provides data rates up to 168 Megabits per second (Mbit/s) to the mobile device (downlink) and 22 Mbit/s from the mobile device (uplink). Technically these are achieved through the use of a multiple-antenna technique known as MIMO (for "multiple-input and multiple-output") and higher order modulation (64QAM) or combining multiple cells into one with a technique known as Dual-Cell HSDPA.
The 168 Mbit/s and 22 Mbit/s represent theoretical peak speeds. The actual speed for a user will be lower. In general, HSPA+ offers higher bitrates only in very good radio conditions (very close to the cell tower) or if the terminal and network both support either MIMO or Dual-Cell HSDPA, which effectively use two parallel transmit channels with different technical implementations.