(
High 
Speed 
Packet 
Access)  A family of high-speed 3G and 4G digital data services governed by the 3rd Generation Partnership Project (3GPP).  Deployed by GSM cellular carriers, at the end of 2014, nearly two billion subscribers were using HSPA worldwide.  Although based on WCDMA, HSPA is a major enhancement with more channels and enhanced modulation schemes.  In addition, HSPA can recover faster from errors (see 
HARQ).
First deployed in the U.S. in 2005, subsequent HSPA+ (HSPA Plus) releases added support for multiple antennas and was designated as a 4G technology by the ITU (see 
MIMO).  See 
LTE, 
4G, 
3GPP, 
DC HSPA, 
cellular generations, 
Wi-Fi vs. cellular, 
WCDMA, 
TDMA and 
GSM.
             Maximum Down   Maximum Up
                 HSDPA        HSUPA
                 Mbps         Mbps
     WCDMA       .4 (QPSK)    .4 (QPSK)
 3GPP
 Release
  #  Name
  5  HSPA       14.4 (16QAM)
  6  HSPA                    5.7 (QPSK)
  7  HSPA+/4G
     2x2 MIMO   28 (16QAM)   11 (16QAM)
  8  2x2 MIMO   42 (64QAM)   11 (16QAM)
  9  2x2 MIMO   84 (64QAM)   23 (16QAM)
 10  2x2 MIMO  168 (64QAM)   23 (16QAM)
 11  4x4 MIMO  336 (64QAM)   35 (64QAM)
 12  4x4 MIMO  336 (64QAM)   35 (64QAM)
 (modulation method)  See QAM and QPSK.
Support for 3G HSPA and 2G EDGE
When this iPhone 3G was in range of a 3G cell tower, it used HSPA.  However, it throttled down to the EDGE (E) channel when 3G was not available.