Have you been to a cell phone store lately? Salespeople throw out all kinds of terms and acronyms to try and close deals. One term you might be hearing a lot these days is "CDMA."
CDMA, also known as code division multiple access, allows more cell phone users to access a given area of bandwidth. Read on to learn more about CDMA.
One way people explain CDMA technology is by comparing cell phone users to people talking in a big room. As everyone speaks at the same time, it can be hard to understand the person with whom you're having a conversation. But if everyone chooses the option of routing for CDMA, it would be as if each pair of people communicating used their own language or code. This way, many people could communicate simultaneously in the same general area, but you could still understand what your conversation partner had to say.
That is how CDMA works: Cell phone users get on their network and are assigned a communication code to use with the person they are calling. This code is called a pseudonoise, or PN, code. Every bit of information in the form of voice data sent by these two people is then altered with the unique PN code. Several conversations using different codes can then use the same channel, but only the two people using a given code hear what is being said.
CDMA technology is considered more secure than other forms of technology that squeeze callers into a given area. Those other forms include FDMA, or Frequency Division Multiple Access, and TDMA, or Time Division Multiple Access.
FDMA is the traditional analog network, with 30 different channels. Using the analog signal is expensive for phone companies, since fewer people can fit in the signals in a given area. Most service providers have eliminated accessing the network through an analog signal. Others charge extra to do so.
TDMA is the technology used on GSM cellular systems. GSM, or Global System for Mobile Communications, is currently the standard for cell phones around the world. Security on GSM systems is considered moderate, although it does use some forms of encryption on data.
CDMA transmission is the most secure technology. It has been used by the U.S. military to ensure security on sensitive phone calls. Experts say the wide signal spread out over a large area makes CDMA calls difficult to detect or scramble.
The same qualities that make CDMA technology secure also make it very reliable. Cell phone retailers sell CDMA technology to customers by explaining that it is the most efficient system. CDMA's encoding and power control create space, so more users are allowed on the network at one time with CDMA than with other forms of transmission.
CDMA proponents also rave about what is called soft handoff. This feature of CDMA ensures smooth transitions and uninterrupted conversations as cell phone users roam among different cell sites.
If you plan on using your phone within the United States and you don't travel often, purchasing a CDMA cell phone is a good decision. The technology used is efficient and provides a good user experience.
However, CDMA technology has not yet been widely adopted. If you travel abroad often, a GSM phone is still the way to go. The GSM system is used around the globe, so roaming is possible as long as you a buy a country-specific SIM card.