| 单词 | DECT (Digital Enhanced Cordless Telecommunications) |
| 释义 | DECT (Digital Enhanced Cordless Telecommunications) Originally known as Digital European Cordless Telecommunications.The pan-European standard for digital cordless telephony, DECT was ratified by the European Telecommunications Standards Institute (ETSI) in 1992, and is intended primarily for indoor applications. Through frequency division multiplexing (FDM), DECT provides 10 carriers in the 1880–1990 MHz band, with channel spacing is at 1.728 MHz. Each channel will support 1.152 Mbps with Gaussian frequency shift keying (GFSK) as the modulation technique. Each channel supports 12 users through time division multiple access (TDMA) and time division duplex (TDD), for a total system load of 120 users.Voice encoding is adaptive differential pulse code modulation (ADPCM) at 32 kbps. DECT supports call handoff, so users can roam from cell to cell at pedestrian speeds as long as they remain within range of the system. DECT antennas can be equipped with optional spatial diversity to deal with multipath fading. Security is provided through authentication and encryption mechanisms. In North America, DECT is the basis for the Personal Wireless Telecommunications (PWT) standard, which operates in the unlicensed 1910–1920 MHz band. PWT-E is an extension into the licensed bands of 1850–1910 MHz and 1930–1990 MHz. See also ADPCM, antenna, authentication, carrier, channel, cordless telephone, digital, encode, encryption, ETSI, FDM, GFSK, handoff, modulation, multipath fading, PWT, PWT-E, spatial diversity, TDD, and TDMA. |
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