CCE-423 Wireless and Cellular Communication

Professor Md Samsuzzaman

References

Book: Jochen H. Schiller - Mobile Communications (2nd Edition) - {Solution}

Group Work

Introduction

• Licensed and Unlicensed Bands

  • 2.4 GHz
  • 5 GHz

• ISM

Slide: Lecture 1

Slide: Chapter 01 - Introduction

Chapter 4 : Wireless Telecommunication System

Slide: Chapter 04 - Wireless_Telecommunication

• Market, GSM, TETRA, UTMS/IMT-2000

Telecommunication Sector

• Development
• History
• Technologies

Source: Statista, GSMA Intelligence

Q&A : Mobile phone feature developments over time

Slide: 22/23-44

GSM

• elements and interface
• system architechture \(\star \star \star\)
• radio subsystem
• cellular network
• frequency bands
• operation subsystem

Question and Tasks

GSM \(\to\) IDMA/FDMA

GSM protocol layes for signalling

• what does what?

Slide: 43-49

• Roaming \(\star \star \star\)
• VLR
• MS+ISDN
• IMSI
  • MCC
  • MNC
• TMSI (4 bytes)
• MSRN

Page: 116

• MTC vs MOC
• Handover
  • MS
  • BTS
  • BSC
  • MSC
• Reasons of hardover
• handover decision

Completed from the slide

Sarna Majumder

References

Book: Jochen H. Schiller - Mobile Communications (2nd Edition) - {Solution}

Introduciton

Wireless Communication

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

Chapter 02 : Wireless Transmission

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

• \(4 \pi d^2\)

• 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

Topics

• Spread Spectrum Technology
• Effects of spreading and interference
• Spreading and frequency selection fading
• DSSS (Direct Sequence Spread Spectrum)
  • Chipping Sequence
  • used in Military
• FHSS (Frequency Hopping Spread Spectrum)
  • Fast hopping (hops/bit)
  • Slow hopping (bits/hop)
• Cell Structure -
  • Detection
  • Interference
• SDM (Space Division Multiplexing)
• FDM (Frequency Division Multiplexing)
  • Frequency broadening
  • FCA, DCA, CH, fixed, dynamix

Exercise Questions: \(\star \star \star\)

• for 3, 4, 5 marks

Exercise Q&A

• Low Frequency \(\to\) Gravity ?!
• ISM (Industry Scientific Medical)
• ISI Mitigation
• Why don't we use CDMA for mobile communication now?

Chapter 3 : Media Access

Topics

• CDMA/CD
• Hidden Terminal + Exposed Terminal
• Near and Far Terminal
• FDD/FDMA
  • FDD (Frequency Division Duplex)
• Aloha/Slotted Aloha
• DAMA (Demand Assigned Multiple Access)
• DAMA: Explicit Reservation
• Access Method DAMA: PRMA
  • Implicit Reservation
• Access Method: Reservation TDMA
• MACA (Multiple Access Collision Avoidance)
• DF MAC
• Polling
• ISMA (Inhibit Sensor Multiple Access)
• Low Frequency \(\to\) gravity ?
• ISM \(\to\) Industry - Scientific - Medical
• ISI Mitigation