(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, cellular vs. Wi-Fi, 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.