HERE is a brief summary block diagram of a typical computer modem.

Vaughn's Summaries

Computer Summaries

30

468 - 768

30

240

Modem Primary Blocks :
Demodulator: Line receiver, A-D converter, digital steering logic,
Modulator: Digital steering logic, D-A converter, Line driver
Logic Control Block: Clock generator, Handshake logic, Tone detection, Data compression, error correction, Hayes command set, command interpreter, FAX modem plus Voice, PCMCIA

Baud Rate

Modulation Method

300 - 1200

FSK - Frequency Shift Keying

2400

QAM - Quadrature Amplitude Modulation

9.6 - 14.4

DPSK - Dual Phase Shift Keying

28.8 - 56.6

DPSK - Dual Phase Shift Keying (Dial-up, AOL)

128K

ISDN - Integrated Services Digital Network

380K

DSL - Digital Subscriber Line (SBC)

1.544M

T1

6M

Cable Modem - DOCSIS (Comcast)

16M

Backplane bus - VME Bus

44.7M

T3

155M

Sonet - Synchronous Optical Network

622M

ATM - Asnychronous Transfer Mode

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