"kontrollkysimuste" - 1 õppematerjal

Side 3 labor(RS-liides ja aeglased modemid) kontrollkysimuste vastused

7. Kontrollküsimused a) Millist andmeedastusprotokolli toetas meie NOKIA modem laboris? V.21 is an ITU-T recommendation for full-duplex communication between two analogue dial- up modems using audio frequency-shift keying modulation at 300 baud to carry digital data at 300 bit/s. It is a variant of the original Bell 103 modulation format. Audio frequency-shift keying (AFSK) is a modulation technique by which digital data is represented as changes in the frequency (pitch) of an audio tone, yielding an encoded signal suitable for transmission via radio or telephone. Normally, the transmitted audio alternates between two tones: one, the "mark", represents a binary one; the other, the "space", represents a binary zero. Meie NOKIA modem kasutas nn. full-duplex kanalit, mis kujutab endast ühendust kahe punkti vahel. Seega üks punkt on telefonivõrgus (dial-up) ja teine võrgukaart. Sellist tüüpi modemid kasutavad tehnoloogiat, mille põhimõte ...