1. Unit -3MultiplexingWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

2. Figure 8-1Multiplexing vs. No MultiplexingWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 3. Multiplexing Enable two or more transmission sources toshare a common circuit Most common forms FDM and TDM FDM associated with analog signal,simultaneous transmission TDM associated with digital signal (couldalso be analog) with time slices3 4. Multiplexing 4 5. Frequency Division Multiplexing Each signal is modulated to a differentcarrier frequency Carrier frequencies separated so signals donot overlap (guard bands) Channel allocated even if no data6 6. Frequency Division Multiplexing Diagram7 7. Figure 8-3FDMWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 8. Figure 8-5Multiplexing, Frequency DomainWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 9. Figure 8-7Demultiplexing, Frequency DomainWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 10. Figure 8-4FDM, Time DomainWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 11. Figure 8-6Demultiplexing, Time DomainWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 12. TDM 13. Synchronous Time DivisionMultiplexing Multiple digital signals interleaved in time May interleave bits, so not necessarilysynchronous transmission Time slots pre-assigned to sources andfixed Time slots allocated even if no data Time slots do not have to be evenlydistributed amongst sources14 14. Time Division Multiplexing15 15. Figure 8-9Synchronous TDMWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 16. TDM, Multiplexing 17. Figure 8-11TDM, DemultiplexingWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 18. Framing Bits 19. Figure 8-13Data RateWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 20. Figure 8-14Asynchronous TDMWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 21. Figure 8-15Frames and Addressesa. Only three lines sending dataWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 22. Figure 8-15-continuedFrames and Addressesb. Only four lines sending dataWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 23. Figure 8-15-continuedFrames and Addressesc. All five lines sending dataWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 24. Wavelength Division Multiplexing Multiple beams of light at different frequency Carried by optical fiber A form of FDM Each colour of light (wavelength) carries separate datachannel 25 25. WDM Operation Same general architecture as other FDM Number of sources generating laser beamsat different frequencies Multiplexer consolidates sources fortransmission over single fiber Optical amplifiers amplify all wavelengths Typically tens of km apart Demux separates channels at the destination26 26. Figure 8-16WDM - Wavelength Division MultiplexingWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 27. Figure 8-16WDM - Wavelength Division MultiplexingWCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998 28. WDM - Wavelength Division Multiplexing