2

(media)

011 V01 V(Noise)

(digitize)(sampling)(quantizing)(coding)

(Baseband) (Broadband) (Carrier)

(1/2)Carrier()

(2/2) (Modulation) (Modulator) (Demodulation) (Demodulator) (Modem)

(1/2)AM/FM

vs.

(2/2) 10Base210Broad36

(1/5)Nonreturn-To-Zero (NRZ, ) 1 = 0 = 100VG-AnyLAN

(2/5)Return-To-Zero (RZ, ) 1 = 0 = 10Mbps ARCNET

(3/5)Nonreturn-To-Zero-Inverted (NRZI,) 1 = 0 = 10BASE-F

(4/5)Manchester () 1 = 0 = 10BASE-T

(5/5)Differential Manchester () 1 = 0 = Token Ring

(1/2)Bipolar Alternate Mark Inversion (Bipolar-AMI, ) T-Carrier Bipolar-8-Zero Substitution (B8ZS, ) T-Carrier High density bipolar 3 (HDB3, 3)E-Carrier Multilevel Transmission 3 (MLT-3, 3)100BASE-TX

(2/2) 5 (PAM5) , 100BASE-T2 1000BASE-T

MLT-3 Mario Mazzola, Luca Cafiero, and Tazio De NicoloMLT-3 0 = 1 = (0+0-)

MLT-3 (1/2)

MLT-3 (2/2)

(Amplitude Modulation, AM)(Amplitude Shift Keying, ASK)01

(Frequency Modulation, FM)(Frequency Shift Keying, FSK)01

(Phase Modulation, PM)(Phase Shift Keying, PSK)(Differential Phase Shift Keying, DPSK)01

QAM (Quadrature Amplitude Modulation) ASK PSK , ,

(Synchronization)(idle)(clock)1%50100

(Simplex), ,

(Half Duplex)()

(Full Duplex)

(Bandwidth) (Signal Bandwidth), ()(bit rate, bps, bits per second)(throughput)100BaseTx100 Mbps(capacity)

(Hertz, Hz)