臺灣博碩士論文加值系統

Orthogonal frequency division multiplexing (OFDM) systems are sensitive to the carrier frequency offset (CFO), which degrades the performance of the system. Therefore, CFO estimation is an important issue in OFDM systems. The focus of this thesis is on CFO estimation in OFDM systems. This thesis first extends frequency analysis (FA) method to estimate carrier frequency offset in OFDM systems with more than two transmitting antennas. Then, we extend the FA method to multi-users. Finally, simulation results show the proposed method works in different settings.

List of Figures vii
Abstract ix
Acknowledgements xi
1 Introduction 1
2 CFO in OFDM Systems 5
2.1 Introduction to OFDM Systems . . . . . . . . . . . . . . . . . . . . . 6
2.2 Carrier Frequency Offset . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.3 Compensation of CFO . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3 FA method for CFO estimation using OSTBC 13
3.1 Review of OSTBC . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.2 Review FA CFO estimation SISO-OFDM . . . . . . . . . . . . . . . . 16
3.3 Review FA CFO estimation MISO-OFDM 2Tx . . . . . . . . . . . . . 19
3.4 Extension FA CFO estimation MISO-OFDM >2Tx . . . . . . . . . . 21
3.5 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4 Application of FA method in Multi-Users Systems 29
4.1 Block-Type Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.2 Comb-Type Arrangement . . . . . . . . . . . . . . . . . . . . . . . . 34
4.3 Effect of Inter-Carrier Interference . . . . . . . . . . . . . . . . . . . . 38
4.4 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5 Conclusion 47
Bibliography 49

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