Unit name | Mobile Communications 3 |
---|---|

Unit code | EENG32500 |

Credit points | 10 |

Level of study | H/6 |

Teaching block(s) |
Teaching Block 1 (weeks 1 - 12) |

Unit director | Professor. Andrew Nix |

Open unit status | Not open |

Pre-requisites | |

Co-requisites |
None |

School/department | Department of Electrical & Electronic Engineering |

Faculty | Faculty of Engineering |

A summary of the various frequency bands and systems in use today is provided. Radiowave propagation is then discussed, covering path-loss, antenna gain, multipath, shadowing and fast fading. System link budgets are developed. Fast fading models are derived and, using the central limit theorem, Rayleigh and Rician distributions are derived. Time dispersion and the impact of inter-symbol interference is introduced. Spaced-time and spaced-frequency correlation functions are derived. The impact of propagation on digital modulation is explained. The Level Crossing Rate and the Average Fade Duration are derived. QPSK and GMSK modulation formats are reviewed with emphasis placed on practical issues, such as synchronisation, band-limiting and the impact of non-linear power amplifiers. Diversity techniques are studied to improve fading performance. Cellular design is presented covering issues such as co-channel interference, frequency re-use, cluster size and handover. The basic cellular radio design equations are developed for capacity and coverage prediction.

Elements: Mobile Communications Prof A.R. Nix

Propagation Principles and Statistics: Rayleigh and Rician fast fading amplitude and phase variations; K-factor; Frequency selective fading, power delay profiles; RMS delay spread, coherence bandwidth and intersymbol interference; Modelling the fast fading envelope; Link Budgets; Level Crossing Rates and Average Fade Duration; Irreducible error rates; Normalised Doppler Spread and Normalised rms Delay Spread.

Modulation and Diversity: QPSK (offset, non-offset and pi/4); Coherent/differential detection; Impact of non-linear amplification; GMSK; Differences between QPSK and GMSK; Generating diversity signals; Switched and selection diversity; Equal gain and maximal ratio combining; Analysis of CT2 (TDMA-TDD) with diversity.

Cellular Design and Capacity: Achieving continuous coverage; Frequency re-use, handover and cluster size; Reuse ratio (D/R); Relationship between cluster size (N) and C/I protection ratio; Calculating cellular capacity, Erlangs; Microcellular networks, future capacity issues.

After completing the unit the student will be able to:

- Understand mobile radio propagation theory

- Develop Matlab models for multipath fading

- Derive and compute radio link-budgets

- Understand how the radio channel distorts digital communications

- Understand how diversity can be used to enhance mobile performance

- Understand the practical differences between GMSK and QPSK

- Design cellular networks based on FDMA and TDMA systems

- Calculate network capacity in terms of subscribers per square kilometre

- Compute the frequency re-use factor as a function of the co-channel protection ratio

After completing the unit the student will be able to:

- Explain mobile radio propagation theory
- Develop Matlab models for multipath fading
- Derive and compute radio link-budgets
- Describe how the radio channel distorts digital communications
- Explain how diversity can be used to enhance mobile performance
- Explain the practical differences between GMSK and QPSK
- Design cellular networks based on FDMA and TDMA systems
- Calculate network capacity in terms of subscribers per square kilometre
- Compute the frequency re-use factor as a function of the co-channel protection ratio

Lectures

Exam, 2 hours, 100% (All ILOs)

- Parsons, J.D., The Mobile Radio Propagation Channel, 2nd Edition, J. Wiley, 2000, ISBN:978-0-471-98857-1 Highly Recommended for part 1.
- Proakis, J., Digital Communications, 4th Edition, McGraw-Hill, 2000, ISBN:0071181830.
- Sklar, B., Digital Communications: Fundamentals and Applications, 2nd Edition, Prentice Hall, 2001, ISBN:0130847887.
- Haykin. S., Communication Systems, 4th Edition, John Wiley, 2000, ISBN:0471178691.
- Rappaport. T.S., Wireless Communications: Principles and Practice, 2001, ISBN:0160422320.
- Macario, R.C.V., Cellular Radio, 1997, ISBN:0070444331.