With 80 percent of the global market share to its credit, Global System for Mobile Communications (GSM) is undoubtedly the most popular mobile phone standard in the world. Next in the line are CDMA, WCDMA, NMT, etc. Among these, CDMA2000 and WCDMA―both supported by 3G technology―seem to have locked horns over the last few years.
The similarity in the names has resulted in a great deal of confusion between the two. Contrary to what most of the people out there believe, the difference between WCDMA and CDMA goes well beyond the bandwidth factor. And more importantly, WCDMA has not been derived from CDMA, but has been developed from the scratch.
An abbreviation for Code Division Multiple Access, CDMA or cdmaOne is a mobile phone standard wherein many usable channels are compressed within the same bandwidth. In order to do this, it uses the 'spread-spectrum' technique, in which electromagnetic energy is spread in order to facilitate signal reception at a wider bandwidth. As a result of this, many people using different cell phones can be put on the same channel in order to share the bandwidth of frequencies. The credit for the development of the CDMA standard goes to the American wireless telecommunications research and development company, Qualcomm.
WCDMA, which is an abbreviation for Wideband Code Division Multiple Access or Wideband CDMA, is a mobile phone standard which combines CDMA and GSM to create an entirely new system. It is one of the most important attributes when it comes to third generation mobile communication network (3G mobile phone technology). Even though the term WCDMA is often used interchangeably with UMTS (Universal Mobile Telecommunications Systems), it is technically incorrect because WCDMA is just an example of UMTS. The credit for its development goes to the largest mobile phone operator in Japan, NTT DoCoMo.
WCDMA Vs. CDMA
As its name suggests, WCDMA uses a wider bandwidth as compared to its counterpart. While CDMA uses frequency bands which are only 1.25Mhz wide, WCDMA uses frequency bands which are 5Mhz wide. Both mobile phone standards also differ in terms of the technologies that they are grouped with; as WCDMA resorts to 3G technology and CDMA resorts to 2G. The fact that CDMA uses 2G technology also puts it in direct competition with the most widely used mobile phone standard GSM, which, in turn, results in GSM - CDMA tussle. The WCDMA standard, on the other hand, is used alongside GSM in order to provide 2G and 3G technologies in a particular area. (You also need to make a note of the fact that the 3G technology introduced by CDMA―CDMA2000 or EV-DO, is a direct competitor for WCDMA.) The fact that WCDMA is a part of the 3G system makes it faster than its 2G counterpart.
At the end of the day, it's safe to conclude that WCDMA is faster than CDMA, and that explains why many people are shifting base. Its biggest advantage is its ability to work in tandem with GSM. If the current trends are to be believed, WCDMA is expected to win this battle sooner or later.