Datalogic Jet Manuel d'utilisateur télécharger pdf (Page 148)

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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.

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Datalogic Jet Manuel d'utilisateur Page 148