Wikipedia defines CDMA as one of the concepts in data communication allowing several transmitters to send information simultaneously over a single communication channel. This allows several users to share a band of frequencies (see bandwidth). This concept is called multiple access. CDMA employs spread-spectrum technology and a special coding scheme (where each transmitter is assigned a code) to allow multiple users to be multiplexed over the same physical channel. By contrast, time division multiple access (TDMA) divides access by time, while frequency-division multiple access (FDMA) divides it by frequency. CDMA is a form of spread-spectrum signaling, since the modulated coded signal has a much higher data bandwidth than the data being communicated.
Today CDMA, or Code Division Multiple Access, is a competing cell phone service technology to GSM. CDMA uses a “spread-spectrum” technique whereby electromagnetic energy is spread to allow for a signal with a wider bandwidth. This allows multiple people on multiple cell phones to be “multiplexed” over the same channel to share a bandwidth of frequencies. With CDMA technology, data and voice packets are separated using codes and then transmitted using a wide frequency range. Since more space is often allocated for data with CDMA, this standard became attractive for 3G high-speed mobile Internet use.
The CDMA standard was designed by Qualcomm, based in San Diego, CA, using Hedy Lamarr’s notion that multiple frequencies could be used to send a single radio transmission or frequency hopping. This notion provided the basis for the CDMA air link, which Qualcomm commercialized in 1995. Hedy Lamarr has been described as one of the most beautiful woman in the world. She was one of Hollywood’s most glamorous actresses of the 1930’s and 40’s starred in such films as Sampson and Delilah and Algiers.
Darryl Laws is the Managing Member at Jermyn Street Capital LLC.
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