Add-On
Attached to a particular hardware or software on a circuit board or software, used to increase functionality.
ADO ActiveX Data Object
Microsoft (MICROSOFT) developed a database (DATABASE) objects (OBJECT) access interface (INTERFACE), to replace DAO and RDO, Microsoft UDA (UNIVERSAL DATA ACCESS) specifications, one of the major components, UDA principal component also includes OLE DB and ODBC.
ADPCM Adaptive Differential Pulse Code Modulation
Of a digitally encoded audio samples, due to encoding only take the difference between two adjacent samples of the record, ADPCM than the required bit (BIT RATE) was lower than standard PCM, ADPCM that the space required for storage of the same voice relatively small, single-disc (CD-ROM) data storage format to use ADPCM to upgrade the capacity from 1 hour to 16 hours, CD-ROM XA and CD-I only use ADPCM encoding. ADPCM and can dynamically adjust the size of the record in order to meet the instantaneous major changes, so that a sample taken less distortion.
ADSL Asymmetric Digital Subscriber Loop
ADSL (Asymmetric Digital Subscriber Line) of a conventional telephone line through a high frequency (25 KHZ - 1 MHZ) data transmission technology, can provide a high transfer rate, but requires line from the user premises to the telephone line from the engine room must be a shorter range and line quality, but also a very good rate of 1.544 MBPS for example, only go as far as 18,000 feet, 6 MBPS only go as far as 8,000 feet.
Asymmetric (ASYMMETRIC) on behalf of the rate of transmission and reception is not the same, the rate of transmission of information from 16 Dao 640 KBPS, and receive data rates from 1.5 Dao 9 MBPS, very suitable for most people browse the Internet through a dial-up manner, because download page or file is usually a greater chance.
ADSL technology, compounded by modulation (MODULATION) technology, divided into DISCRETE MULTITONE (DMT) and CARRIERLESS AMPLITUDE PHASE (CAP) of two, in general, DMT because of the performance of echo cancellation and noise-off of ANSI, ETSI, and ITU used.
However, the use of similar techniques to send and receive the same speed technology is called SDSL, all using similar technology (DSL) transmission method is known as XDSL. |
