Chapter 10 Multiple Access

10.1 Introduction

What is the Multiple Access?

Answer: A allocated frequency bandwidth is used by many users for simultaneous communication

10.2 Frequency Division Multiple Access (FDMA)

10.3 Time Division Multiple Access (TDMA)

10.4 Spread Spectrum and Code Division Multiple Access

1) SSC (spread spectrum communication) Principles

2) SSC (spread spectrum communication) advantages

- Interference rejection

- Good security

- Good anti-jamming capability

- Spectrum efficiency improved

- Graceful degradation as the number of users is increased.

- Digital IC available

3) SSC types

- DSSS (direct sequence SS): use a PN (pseudo noise) code to spread the spectrum

- FHSS (frequency hopping SS): carrier frequency is randomly changed

- Time hopping: pulse position modulation. Use a un

- Chirp

4) DSSS (= CDMA)

5) FHSS

6) Time Hopping SS

7) Chirp SS