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TDMA
Time division multiple access (TDMA) is digital transmission technology that allows a
number of users to access a single radio-frequency (RF) channel without interference
by allocating unique time slots to each user within each channel. The TDMA digital
transmission scheme multiplexes three signals over a single channel. The current
TDMA standard for cellular divides a single channel into six time slots, with each
signal using two slots, providing a 3 to 1 gain in capacity over advanced mobile-
phone service (AMPS). Each caller is assigned a specific time slot for transmission.
Toggle key
Pressing a toggle key activates the state. The state remains active until the toggle
key is pressed again.
USB
Universal Serial Bus.
Type of serial bus that allows peripheral devices (disks,
modems, printers, digitizers, data gloves, etc.) to be easily connected to a computer.
A “plug-and-play” interface, it allows a device to be added without an adapter card
and without rebooting the computer (the latter is known as hot-plugging). The USB
standard, developed by several major computer and telecommunications companies,
supports data-transfer speeds up to 12 megabits per second, multiple data streams,
and up to 127 peripherals.
WLAN
A Wireless Local Area Network links devices via a wireless distribution method
(typically spread-spectrum or OFDM radio), and usually provides a connection
through an access point to the wider internet. This gives users the mobility to move
around within a local coverage area and still be connected to the network.
WPAN
A Wireless Personal Area Network is a personal area network - a network for
interconnecting devices centered around an individual person's workspace - in which
the connections are wireless. Typically, a wireless personal area network uses some
technology that permits communication within about 10 meters - in other words, a
very short range.
WWAN
Stands for "Wide Area Network." It is similar to a Local Area Network (LAN), but it is
not limited to a single location and it uses Mobile telecommunication cellular network
technologies such as UMTS, GPRS, CDMA2000, GSM, CDPD, Mobitex, HSDPA or
3G to transfer data. WWAN connectivity allows a user with a laptop and a WWAN
card to surf the web, check email, or connect to a Virtual Private Network (VPN) from
anywhere within the regional boundaries of cellular service.
