馮世邁臺灣大學：電信工程學研究所羅宗惠Lo, Tzung-HwuiTzung-HwuiLo2007-11-272018-07-052007-11-272018-07-052004http://ntur.lib.ntu.edu.tw//handle/246246/58875The OFDM transceiver has enjoyed great success in many wideband communication systems in recent years, and has been adopted in standards for various applications such as ADSL, VDSL, wireless LAN, digital audio and video broadcasting, etc. Two of the attractive features are its low complexity and the ability to combat inter-symbol interference(ISI). Although the OFDM systems are used widely, however it is also well-known that the OFDM transceiver has poor frequency characteristics. To improve the frequency characteristics of transceivers, filter banks (FB) are often proposed as a solution. FBs have the advantage of high stopband attenuation but their complexity is very high. To reduce the implementational cost, we employ DFT modulated filter banks, where the transceivers can be efficiently implemented using fast Fourier transform. In this thesis, FB transceivers with overlapping block transmission are considered. For multi-path fading channels, these FB transceivers suffer from serious ISI. We will show that the SIR (signal to interference ratio) can be formulated in terms of the FB free parameters. Given a fixed receiver (or transmitter) with good frequency characteristics, the transmitter (or receiver correspondingly) can be designed to maximize SIR for multi-path fading channels. The problem of SIR maximization can be formulated into an eigenvector problem. In addition, we also proposed a new method to design these DFT bank transceivers with good transmit and receiver filters. In the new design, the free parameters of the transmitter and receiver are split into 2 parts: one part for frequency response optimization and one part for SIR optimization. An iterative procedure is employed to solve the design problem. Simulation results show that the DFT bank transceivers can enjoy both good frequency characteristics and a moderate SIR value for multi-path fading channels. Moreover, the proposed new method leads to a significant improvement over the original design.List of Table vi List of Figure viii Abstract x Acknowledgement xii Chap 1 :Introduction 1 Chap 2：Filter Bank Transceiver（FBT）System 5 2.1 … Introduction to FBT System 6 2.2 … Efficient Implementation of FBT System 10 2.3 … OFDM System 13 2.4 … Conclusion 17 Chap 3：DFT Modulated Filter Bank Transceivers 19 3.1 … PR Condition and ISI-Free Condition 20 3.2 … SIR Optimized for Known Channels 24 3.3 … SIR Optimized for Multipath Fading Channels 27 3.4 … Iteration Procedure 31 Chap 4：Design of Filter Bank Transceiver With Frequency Response Constraints 35 4.1 … FBT System With Frequency Response Constraints 36 4.2 … FBT System With Good Tx and Rx Filters 40 4.3 … Design Using Weighted SIR Criteria 41 4.4 … Weighted Eigenfilter Design 44 4.5 … Performance Analysis 47 Chap 5：Filter Bank Transceiver with Bit Loading and Error Correcting Codes 57 5.1 … Optimal Bit Loading for FBT System 58 5.2 … Convolution Code for FBT System 61 5.3 … Performance Analysis 62 Chap 6：Conclusion 71 Appendix A：Tabular Method 73 Bibliography 771089429 bytesapplication/pdfen-US多載波傳輸濾波器組傅立葉MulticarrierFilter BanksDFTthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/58875/1/ntu-93-R91942088-1.pdf