CCE-423 Wireless and Cellular Communication

Professor Md Samsuzzaman

Reference Book:

Assignment: Research Paper Study (Group)

Checklist for Your Group:

  • Video presentation is recorded (slides + face).
  • Video is over 10 minutes long.
  • Presentation is in English.
  • Q&A document is prepared with a cover page.
  • PowerPoint file is finalized.
  • All three files are named correctly using your Student ID.
  • All files are uploaded to Google Classroom before 11:59 AM.

Google Classroom: Link

Introduction

  • Licensed and Unlicensed Bands

    • 2.4 GHz
    • 5 GHz
  • ISM

Sarna Majumder

Reference Book: Jochen H. Schiller - Mobile Communications (2nd Edition)

Introduciton

Wireless Communication

  • Evolution of wireless communicaiton \(\to\) self study
  • Block diagram of wireless communication

To-Do

Block diagram of encrypted communicaiton

Chapter 02 : Wireless Transmission

  • Compostite Signal \(\to\) Fourier transform
  • Isotropic Radiator (Antenna) \(\to\) ideal antenna

Note

Signals attenuate in space

  • \(4 \pi d^2\)

  • Simple dipole + monopole

  • directed and sectorized
  • diversity

Smart Antenna

  • Switched Beam
  • Adaptive Array

Signal Propagation Range

  • Transmission
  • Detection
  • Interference range

Signal Propagation

Multipath Propagation

  • delay spread (cause)
  • Inter Symbol Interference (ISI) (reason)

2.14.1 Effects of Mobility

  • fading
    • short time
    • long time
  • doppler effect

  • Engineers calculates these:

    • (Ray Tracing)

Multiplexing 4 dimentions:

  • space (s) \(\to\) Guard Space needed
  • time (t)
  • frequency (f)
  • code (c)

2.16.1 Frequency Multiplex

  • frequency bands \(\to\) static
  • Adjacent Channel Interference (ACI)

Time Multiplex

  • Co-channel Interference

Time and Frequency

  • certain frequency band for a certain time
  • GSM

Code Multiplex

  • Orthogonal Code \(\to\) multiplication (of two code) = 0

2.20.1 Modulation

Digital Modulation

Advanced Frequency Shift Keying (MSK)

  • even, odd bits
  • doubling each bits
  • \(f_1\) \(\to\) lower frequency
  • \(f_2\) \(\to\) higher frequency