03. physical2

03. physical2 - Physical Layer 2 Multiplexing Spread...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Physical Layer 2 Multiplexing, Spread Spectrum
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Communication Networks © Kang Xi, Polytechnic Institute of NYU 2 Multiplexing
Background image of page 2
Communication Networks © Kang Xi, Polytechnic Institute of NYU 3 Objectives ± The purposes and requirements of multiplexing ± The principles of FDM, TDM, WDM and statistical multplexing ± DSL
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Communication Networks © Kang Xi, Polytechnic Institute of NYU 4 Why Multiplexing? ± The fact ² # of point-to-point communications: large ² # of channels: small ² Dedicated channel: infeasible ± The requirement ² Multiple users share the same channel ² QoS of end users can be satisfied ± Definition ² Multiplexing: Channel sharing
Background image of page 4
Communication Networks © Kang Xi, Polytechnic Institute of NYU 5 Framework ± Regard a user-user communication as a stream ± Multiplexer (Mux) ² Combine multiple streams ± De-Multiplexer (DeMux) ² Pick out one/more streams out of the aggregation. Mux DeMux
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Communication Networks © Kang Xi, Polytechnic Institute of NYU 6 Benefit ± Wired networks ² Each wire (copper, fiber) carries multiple streams ² Total # of wires reduced: low cost ² Dedicated links between users are not necessary ± Wireless networks ² Channels are naturally shared, dedicated transmission media unavailable ² Enables simultaneous wireless communication with no interference
Background image of page 6
Communication Networks © Kang Xi, Polytechnic Institute of NYU 7 General Principles for Mux/DeMux ± Theoretically feasible ² The aggregated streams CAN be separated again ± Technically feasible ² Acceptable complexity and cost ± High multiplexing gain ² Maximize channel utilization
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Communication Networks © Kang Xi, Polytechnic Institute of NYU 8 FDM: Example ± Example ² Two speakers ² One listener ² Listener can hear either ² Key: speakers have different voice (frequency) ² Note: not 100% FDM Mux DeMux
Background image of page 8
Communication Networks © Kang Xi, Polytechnic Institute of NYU
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 11/02/2010 for the course EE 136 taught by Professor Kang xi during the Spring '10 term at NYU Poly.

Page1 / 43

03. physical2 - Physical Layer 2 Multiplexing Spread...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online