HSPA vs UMTS vs WCDMA

HSPA>UMTS>WCDMA

WCDMA:

Wideband Code Division Multiple Access (WCDMA) is third generation air interface, a type of 3G cellular network. W-CDMA is the technology behind the 3G UMTS standard and is allied with the 2G GSM standard with the International Telecommunication Union (ITU). A speed up to 384Kbps can only be reached even if operator is providing more than that. WCDMA is commonly referred to as 3G. 

UMTS:

Universal Mobile Telecommunication System (UMTS) is a 3^rd generation mobile cellular technology. It enables transmission of text, voice, video, and multimedia with up to 2Mbps speed. UMTS used WCDMA and other air interfaces for data transmission.

One can say UMTS is a full-fledged system and one part of it is WCDMA.

HSPA:

High Speed Packet Access (HSPA) is combination of HSDPA (downlink) and HSUPA (uplink). HSDPA provides a smooth evolutionary path for Universal Mobile Telecommunications System (UMTS) networks allowing for higher data capacity. It supports increased peak data rates of up to 14Mbps in the downlink and 5.76Mbps in the uplink. It is an evolution of the W-CDMA standard, designed to increase the available data rate by a factor of 5 or more.

One can say that HSPA is enhancer of UMTS. It allows mobile communications devices such as cell phones using the UMTS network to achieve data transfer speeds of up to 14 Mbps.

HSPA is commonly referred to as 3.5G.

WCDMA	UMTS	HSDPA
WCDMA is technology It is an air interface standard.	UMTS uses W-CDMA as the underlying air interface. It also uses radio access network: (UMTS Terrestrial Radio Access Network-UTRAN), the core network (Mobile Application Part- MAP) and USIM based authentication routines	It allows UMTS network to achieve data transfer speeds of up to 14 Mbps. It is an additional feature of UMTS.
3G	3G	3.5G
Speed - 384Kbps	Speed - 2Mbps	Speed - 14 Mbps (downlink)               5.76 Mbps (uplink)