Mobile Communications

• The dates for lectures and tutorials are announced at the beginning of the corresponding semester.

• Detailed information about location and timings on Open Timetable

• Participants:
  • Communications and Signal Processing
  • Elektrotechnik und Informationstechnik
  • Ingenieurinformatik
  • Medientechnologie
  • Wirtschaftsingenieurwesen
• Further interested parties are very welcome.
• Information on Modultafeln

1    Introduction
     +    Overview of mobile communication standards and applications (1G - 5G)
     +    5G Vision and Requirements
     +    The Wireless Channel
          -    Path loss
          -    Shadowing
          -    Fast fading
2    Mobile Communication Channels
     +    Review: Representation of Bandpass Signals and Systems
2.1    Propagation Modelling
     +    Time variance (Doppler)
     +    Time-varying multipath channels
          -    Transmission functions of the time-varying channel (1st set of Bello functions)
          -    4 ways to calculate the received signals
          -    Identification of linear time-varing (LTV) systems
2.2    Statistical Characterization of Multipath Channels
     +    Rayleigh channel (fading)
     +    Rician channel
     +    Channel Correlation Functions and Power Spectra of Fading Multipath Channels
          -    Time-variations of the channel
          -    Characterization of a WSSUS channel (2nd set of Bello functions)
2.3    The effect of signal characteristics on the choice of a channel model
     +    Frequency non-selective channels
     +    Frequency selective channels
          -    Truncated tapped delay line model of a frequency selective channel
2.4    Space-Time Channel and Signal Models
     +    Generalization of the time-varying channel impulse response
          -    First set of Bello functions extended to the spatial domain
          -    Example: specular L paths model (continued)
     +    Homogeneous channels (WSSUS-HO model)
     +    Correlation functions and power spectra extended to the spatial domain
          -    Second set of Bello functions extended to the spatial domain
          -    Coherence time, coherence frequency, coherence distance
     +    Transmission functions extended to transmit and receive antenna arrays (MIMO)
          -    Definition of the array manifold
     +    Notation for SISO, SIMO, MISO, and MIMO channels
          -    Example: L paths model (continued)
     +    Classical IID Channel Model
     +    Extended MIMO Channel Models
          -    Spatial fading correlation at the transmit and the receive arrays
               >    Review of the eigenvalue decomposition (EVD)
               >    General model
               >    Kronecker model
          -    Additional Line-of-Sight (LOS) component
     +    Sampled signal model for SISO, SIMO, MISO, and MIMO channels
3    Capacity of Space-Time Channels
3.1    Differential Entropy and Mutual Information for Continuous Ensembles (review)
3.2    Capacity Theorem for the AWGN SISO Case (review)
3.3    Capacity of the Flat Fading MIMO channel
     +    Differential entropy for CSCG random vectors
     +    Choosing Rss (with and without CSI @ the transmitter)
          -    Singular Value Decomposition (SVD)
          -    Special case: uncorrelated Rayleigh fading and Mt very large
     +    Parallel Spatial Sub-Channels
          -    Design of the precoder and the decoder for MIMO systems with CSI at the transmitter
          -    Optimum power allocation (waterpouring algorithm) with CSI at the transmitter
     +    SIMO Channel Capacity
     +    MISO Channel Capacity
     +    Capacity of Random MIMO Channels
          -    Ergodic vs. non-ergodic channels
          -    Ergodic capacity
               >    Examples, e.g., Rice, correlation
          -    Outage capacity
3.4    Capacity of the Frequency Selective MIMO channel
     +    Space-Frequency Waterpouring
4    Transmission Techniques
4.1    Bit error probability
     +    Binary signaling over Rayleigh fading channel
4.2    Diversity techniques for fading multipath channels
     +    Frequency diversity
     +    Time diversity
     +    Space diversity
     +    Post-processing techniques
          -    Selection combining, equal gain combining, maximum ratio combining, square-law combining
4.3    Approximation of the Probability of Symbol Error
     +    Fading channel with D-fold diversity
     +    Chernoff bound
     +    Coding gain vs. diversity gain
5    Space-Time Processing
5.1    Receive antenna diversity (SIMO channel): MRC
5.2    Transmit antenna diversity
     +    MISO channel unknown to the transmitter: Alamouti scheme (1998)
     +    MISO channel known to the transmitter: MRT
     +    MIMO channel unknown to the transmitter: Alamouti scheme (1998)
     +    MIMO channel known to the transmitter: DET
     +    Definiton of the effective diversity order
     +    Summary: Diversity of space-time-frequency selective channels
5.3    Space-Time Coding without channel state information (CSI) at the transmitter
     +    Space-Time Coding for frequency flat channels
     +    Space-Time codeword design criteria
          -    definition of the pairwise error probability (PEP)
          -    rank criterion
          -    determinant criterion
     +    Orthogonal Space-Time Block Codes (OSTBCs)
          -    OSTBCs for real-valued constellations
          -    OSTBCs for complex-valued constellations
     +    Spatial Multiplexing (SM) as a Space-Time Code
     +    Encoder Structures for Spatial Multiplexing (SM)
          -    horizontal encoding
          -    vertical encoding
          -    diagonal encoding (D-BLAST transmission)
5.4    Gains achievable with smart antennas
     +    Array Gain
     +    Diversity Gain
     +    Spatial Multiplexing Gain
     +    Interference Reduction Gain
          -    frequency reuse and cluster sizes
5.5    Multi-User MIMO Systems
     +    Block Diagonalization
5.6    Multiple access schemes
     +    OFDM
     +    Single carrier vs. OFDM vs. spread spectrum

• A. Paulraj, R. Nabar, and D. Gore, Introduction to Space-Time Wireless Communications.
  Cambridge University Press, 2003.

   

• A. Hottinen, O. Tirkkonen, and R. Wichman, Multi-antennas Transceiver Techniques for 3G and Beyond.
  Wiley, 2003.

   

• S. Haykin, Communication Systems.
  John Wiley & Sons, 4th edition, 2001.

   

• S. Haykin and M. Moher, Modern Wireless Communications.
  Pearson Education, Inc., 2005.

   

• F. Jondral and A. Wiesler, Grundlagen der Wahrscheinlichkeitsrechnung und stochastischer Prozesse für Ingenieure.
  Teubner Verlag, Stuttgart/Leipzig, 2000.

   

• A. Papoulis, Probability, Random Variables, and Stochastic Processes.
  McGraw-Hill, 2nd edition, 1984.

   

• T. S. Rappaport, Wireless Communications.
  Prentice Hall, 1996.

   

• J. Proakis, Digital Communications.
  McGraw-Hill, 4th edition, 2001.

   

• G. L. Stüber, Mobile Communication.
  Kluwer Academic Publishers, 2nd edition, 2001.

   

• R. Steele and L. Hanzo, eds., Mobile Radio Communications.
  Wiley, 2nd edition, 1999.

   

• S. Saunders, Antennas and Propagation for Wireless Communication Systems.
  Wiley, 1999.

   

• A. Graham, Kronecker Products and Matrix Calculus with Applications.
  Halsted Press, 1981.

   

• E. G. Larson, P. Stoica, and G. Ganesan, Space-Time Block Coding for Wireless Communications.
  Cambridge University Press, 2003.

   

• H. Bölcskei, D. Gesbert, C. B. Papadias, and A.-J. van der Veen, eds., Space-Time Wireless Systems From Array Processing to MIMO Communications.
  Cambridge University Press, 2006.

   

• E. Biglieri, R. Calderbank, A. Constantinides, A. Goldsmith, A. Paulraj, and H. V. Poor, MIMO Wireless Communications.
  Cambridge University Press, 2007.

   

• C. Oestges and B. Clerckx, MIMO wireless communictions.
  Academic Press, 1 ed., 2007.

   

• Q. H. Spencer, A. L. Swindlehurst, and M. Haardt, “Zero-forcing methods for downlink spatial multiplexing in multi-user MIMO channels,” IEEE Transactions on Signal Processing, vol. 52, pp. 461-471, Feb. 2004, received the 2009 Best Paper Award of the IEEE Signal Processing Society, PDF.

   

• Q. H. Spencer, C. B. Peel, A. L. Swindlehurst, and M. Haardt, “An introduction to the multi-user MIMO downlink,” IEEE Communications Magazine, pp. 60-67, Oct. 2004, special issue on MIMO Systems, PDF

   

• Note: You will receive the password to open the PDF files from Prof. Haardt in the lecture.

• Homework assignments will be announced at the beginning of the respective semester

Homework assignments will be given to you as the semester progresses. Most homework problems will be to show some results discussed in class. This will involve theoretical proofs as well as simulation studies using Matlab. In many cases, assignments can involve examining the performance of a system or extracting key parameters from measurements. Most of the topics covered by the course is best learned by working with the problems through a combination of computer simulations and theoretical analysis. The homework is therefore one of the most important parts of the course.
Cooperative group study on the homework is encouraged, but simply copying someone else's work is unethical and will leave you unprepared for exams. Significant insight can be gained by studying with another student or in a group, provided you discipline yourself to find your own solutions first before comparing results. Rely on other's help only when you have exhausted all of your own ideas or have made no progress for an extended period of time.

Mobile Communications, Complete (PStO since 2021)

• written exam (150 min)
• allowed: summary sheets: 4 double-sided A4 pages with name and matriculation number
• not allowed: anything else, e.g., notes, books, calculators, cell phones, any other electronic devices

Mobile Communications, Part 1 (PStO since 2021)

• written exam (75 min)
• allowed: summary sheets: 2 double-sided A4 pages with name and matriculation number
• not allowed: anything else, e.g., notes, books, calculators, cell phones, any other electronic devices

Mobile Communications (PStO before 2021)

• written exam (120 min)
• allowed: summary sheets: 4 double-sided A4 pages with name and matriculation number
• not allowed: anything else, e.g., notes, books, calculators, cell phones, any other electronic devices

Sample exams

• Winter semester 2010/11: [PDF]
• Summer semester 2010: [PDF]