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CDMA TECHNOLOGY

CDMA TECHNOLOGY

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CDMA TECHNOLOGY

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  1. CDMA TECHNOLOGY INSTRCTOR: NAZILA SAFAVI

  2. What This Course is All About?

  3. What is Multiple Access?

  4. What is a Channel?

  5. Defining Our Terms

  6. Spread Spectrum Principles

  7. CDMA Spreading Principle:Anything We Can Do, We Can Undo

  8. Shipping and Receiving” via CDMA

  9. CDMA Spreading Principle:Multiple Successive Spreadings are Reversible

  10. How Many Spreading Sequences Do We Need?(Discriminating Among Forward Code Channels

  11. How Many Spreading Sequences Do We Need?(Discriminating Among Base Station

  12. How Many Spreading Sequences Do We Need?(Discriminating Among Reverse Code Channels

  13. CDMA Magic Spreading Tool #1:Walsh Codes Note: Example of orthogonality – The coordinates used to describe the position of a mobile station at a certain time: latitude (North or South of the Equator), longitude (East or West of Greenwich), altitude (relative to sea level), and time. A change in any of these magnitudes does not affect the other three, therefore they are “orthogonal”.

  14. Correlation and Orthogonality

  15. CDMA Magic Spreading Tool #2:The Short PN Sequences

  16. CDMA Magic Spreading Tool #3:The Long PN Sequence (User Long Code)

  17. CDMA Code Channels in the Forward Direction

  18. Coding Process on CDMA Forward Code Channels MSC

  19. CDMA Code Channels in the Reverse Direction

  20. Coding Process on CDMA Reverse Code Channels MSC

  21. CDMA’s “Magic” Spreading SequencesSummary of Characteristics & Functions

  22. Basic Spreading & De-spreading Example:User’s Data Spread, Sent, Recovered

  23. Spectrum Usage and System Capacity:Signal Bandwidth, Vulnerability, and Frequency Reuse

  24. Relationship Between Eb/N0 And S/N

  25. CDMA Advantage (13 kb vocoder at full rate)

  26. Reverse Link Interference Scenarios

  27. CDMA Capacity Considerations

  28. Coexistence of CDMA with Other Systems

  29. Overlaying CDMA on an AMPS System

  30. CDMA 800 MHz Cellular Spectrum Usage

  31. CDMA 800 MHz Cellular Spectrum Usage The above table is an example of CDMA channel allocation, in chronological order, which allows maximum CDMA channel packing. Note: a) requires frequency coordination with non-cellular interferes b) requires frequency coordination with A-side carrier

  32. Deploying CDMA on the 1900 MHz band

  33. CDMA PCS 1900 MHz Spectrum Usage

  34. CDMA PCS 1900 MHz Spectrum Usage PCS Band A 493 BTAs (Basic Trading Areas) are grouped into 51 MTAs (Metropolitan Trading Area s). The following tables are examples of CDMA channel allocation, in chronological order, which allow maximum CDMA channel packing. Each table represents the “preferred” set of CDMA channels according to J-STD-008.

  35. PCS Band D PCS Band E PCS Band B PCS Band C PCS Band F