Wireless glossary
3G (Third Generation Wireless): The next wave of wireless technologies. Analog was the first generation and digital was the second. The third will include wireless broadband and high-speed data transfer, technologies that will make the Internet and intranets more accessible to mobile devices.
802.11: A wireless Ethernet standard that can be deployed today. Wireless LANs use this standard to connect devices within a 300-foot radius. 802.11a and 802.11b are two faster variants of 802.11.
AMPS (Advanced Mobile Phone Systems): A term used for analog technologies, the basis of the US cellular market.
Analog: A way that radio signals can be changed to carry information. Analog is considered the first generation of wireless technologies. Some phones are both analog and digital so they can find an analog signal when they are out of digital range.
Bandwidth: A range of frequencies that can carry a signal.
Bluetooth: A specification for short range radio connections between devices. Bluetooth works within a 30-foot range.
CDMA (Code Division Multiple Access): A second-generation spread spectrum technology that allocates bandwidth for digital users. A spread spectrum allows a call to be carried on several frequencies, so that when one frequency is lost another picks up the transmission without the connection being broken.
CDPD (Cellular Digital Packet Data): A method by which data is transferred on unused analog cellular networks. CDPD is a way to access the Internet from a wireless device at speeds up to 19.2 Kbps.
Circuit Switched: A way to get a direct dedicated connection between a sender and a receiver. A traditional phone line is circuit switched.
EDGE (Enhanced Data GSM Environment): A faster version of GSM that would carry data at rates up to 384 Kpbs.
FDMA (Frequency Division Multiple Access): The division ofthe frequency bands used for wireless communications into 30 channels, each channel transmits one element of voice or data. FDMA is the basis of the analog AMPS (see above) system. When FDMA is combined with TDMA each channel is multiplied into three.
FH (Frequency Hopping): A method by which information (voice or data) is put into packets and then the packets are spread out on different frequencies. In the case of a phone call
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