Adaptive Wireless Transceivers - Turbo-Coded, Turbo-Equalised And Space-Time Coded Tdma, Cdma And Ofdm Systems

Adaptive Wireless Transceivers provides the reader with a broad overview of near-instantaneously adaptive transceivers in the context of TDMA, CDMA and OFDM systems. The adaptive transceivers examined employ powerful turbo codecs, turbo equalisers and space-time codecs, equipping the reader with a future-proof technological road map. It demonstrates that adaptive transceivers are capable of mitigating the channel quality fluctuations of the wireless channel as a lower-complexity alternative to space-time coding. By contrast, if the higher complexity of multiple transmitters and multiple receiver-assisted systems is deemed acceptable, the advantages of adaptability erode.

• Provides an in-depth introduction to channel equalisers and Kalman filtering and discusses the associated complexity versus performance trade-offs
• Introduces wideband near-instantaneously adaptive transceivers and studies their performance both with and without turbo channel coding
• Describes how to optimise adaptive modulation mode switching and highlights a range of practical considerations
• Introduces neural network based channel equalisers and discusses Radial Basis Function (RBF) assisted equalisers embedded into adaptive modems supported by turbo channel coding and turbo channel equalisation
• Employs the above adaptive principles also in the context of CDMA and OFDM transceivers and discusses the pros and cons of space-time coding versus adaptive modulation

Researchers, advanced students and practising development engineers working in wireless communications will all find this valuable text an informative read.

1 Prologue.

1.1 Motivation of the Book.

1.2 Adaptation Principles.

1.3 Channel Quality Metrics.

1.4 Transceiver Parameter Adaptation.

1.5 Milestones in Adaptive Modulation History.

1.6 Outline of the book.

I Near-instantaneously Adaptive Modulation and Filtering Based Equalisation.

2 Introduction To Equalizers.

2.1 Coherent Demodulation of Square-QAM.

2.2 Intersymbol Interference.

2.3 Basic Equalizer Theory.

2.4 Signal to Noise Ratio Loss of the DFE.

2.5 Equalization in Multi-level Modems.

2.6 Review and Discussion.

3 Adaptive Equalization.

3.1 Derivation of the Recursive Kalman Algorithm.

3.2 Application of the Kalman Algorithm.

3.3 Complexity Study.

3.4 Adaptive Equalization in Multilevel Modems.

3.5 Review and Discussion.

4 Adaptive Modulation.

4.1 Adaptive Modulation for Narrow-band Fading Channels.

4.2 Power Control Assisted Adaptive Modulation.

4.3 Adaptive Modulation and Equalization in a Wideband Environment.

4.4 Review and Discussion.

5 Turbo-Coded and Turbo-Equalised Adaptive Modulation.

5.1 Turbo Coding.

5.2 System Parameters.

5.3 Turbo Block Coding Performance of the Fixed QAM Modes.

5.4 Fixed Coding Rate, Fixed Interleaver Size Turbo Coded AQAM.

5.5 Fixed Coding Rate. Variable Interleaver Size Turbo Coded AQAM.

5.6 Blind Modulation Detection.

5.7 Variable Coding Rate Turbo Block Coded Adaptive Modulation.

5.8 Comparisons of the Turbo Block Coded AQAM Schemes.

5.9 Turbo Convolutional Coded AQAM Schemes.

5.10 Turbo Equalization.

5.11 Burst-by-Burst Adaptive Wideband Coded Modulation.

5.12 Review and Discussion.

6 Adaptive Modulation Mode Switching Optimization.

6.l Introduction.

6.2 Increasing the Average Transmit Power as a Fading Counter-Measure.

6.3 System Description.

6.4 Optimum Switching Levels.

6.5 Results and Discussions.

6.6 Review and Discussion.

7 Practical Considerations of Wideband AQAM.

7.1 Impact of Error Propagation.

7.2 Channel Quality Estimation Latency.

7.3 Effect of CO-channel Interference on AQAM.

7.4 Review and Discussion.

II Near-instantaneously Adaptive Modulation and Neural Network Based Equalisation.

8 Neural Network Based Equalization.

8.l Discrete Time Model for Channels Exhibiting Intersymbol Interference.

8.2 Equalization as a Classification Problem.

8.3 Introduction to Neural Networks.

8.4 Equalization Using Neural Networks.

8.5 Multilayer Perceptron Based Equaliser.

8.6 Polynomial Perceptron Based Equaliser.

8.7 Radial Basis Function Networks.

8.8 K-means Clustering Algorithm.

8.9 Radial Basis Function Network Based Equalisers.

8.10 Scalar Noise-free Channel Output States.

8.11 Decision Feedback Assisted Radial Basis Function Network Equaliser.49

8.12 Simulation Results.

8.13 Review and Discussion.

9 RBF-Equalized Adaptive Modulation.

9.l Background to Adaptive Modulation in a Narrowband Fading Channel.

9.2 Background on Adaptive Modulation in a Wideband Fading Channel.

9.3 Brief Overview of Part I of the Book.

9.4 Joint Adaptive Modulation and RBF Based Equalization.

9.5 Performance of the AQAM RBF DFE Scheme.

9.6 Review and Discussion.

10 RBF Equalization Using nrbo Codes.

10.1 Introduction to Turbo Codes.

10.2 Jacobian Logarithmic RBF Equalizer.

10.3 System Overview.

10.4 Turbo-coded RBF-equalized M-QAM Performance.

10.5 Channel Quality Measure.

10.6 Turbo Coding and RBF Equalizer Assisted AQAM.

10.7 Review and Discussion.

11 RBF Turbo Equalization.

11.1 Introduction to Turbo equalization.

11.2 RBF Assisted Turbo equalization.

11.3 Comparison of the RBF and MAP Equaliser.

11.4 Comparison of the Jacobian RBF and Log-MAP Equaliser.

11.5 RBF Turbo Equaliser Performance.

11.6 Reduced-complexity RBF Assisted Turbo equalization.

11.7 In-phase/Quadrature-phase Turbo equalization.

11.8 Turbo Equalized Convolutional and Space Time Trellis Coding.

11.9 Review and Discussion.

III Near-Instantaneously Adaptive CDMA and Adaptive Space-Time Coded OFDM.

12 Burst-by-Burst Adaptive Multiuser Detection CDMA.

12.1 Motivation.

12.2 Multiuser Detection.

12.3 Multiuser Equaliser Concepts.

12.4 Adaptive CDMA Schemes.

12.5 Burst-by-Burst AQAM/CDMA.

12.6 Review and Discussion.

13 Adaptive Multicarrier Modulation.

13.1 Introduction.

13.2 Orthogonal Frequency Division Multiplexing.

13.3 OFDM Transmission over Frequency Selective Channel.

13.4 OFDM Performance with Frequency Errors and Timing Errors.

13.5 Synchronization Algorithms.

13.6 Adaptive OFDM.

13.7 Pre-Equalization.

13.8 Review and Discussion.

14 Space-Time Coding versus Adaptive Modulation.

14.1 Introduction.

14.2 Space-Time Trellis Codes.

14.3 Space-Time CodedTransmissionOver Wideband Channels.

14.4 Simulation Results.

14.5 Space-Time Coded Adaptive Modulation for OFDM.

14.6 Review and Discussion.

15 Conclusions and Suggestions for Further Research.

15.1 Book Summary and Conclusions.

15.2 Suggestions for Future Research.

15.3 Closing Remarks.

A Appendices.

A.1 Turbo Decoding and Equalization Algorithms.

A.2 Least Mean Square Algorithm.

A.3 Minimal Feedforward Order of the RBF DFE [Proof].

A.4 BER Analysis of Type-I Star-QAM.

A.5 Two-Dimensional Rake Receiver.

A.6 Mode Specific Average BEP of Adaptive Modulation.

Bibliography.

Index.

Author Index.