本論文在通用濾波正交分頻多工(Universal Filtered Orthogonal Frequency-Division Multiplexing, UF-OFDM)的系統基礎下，提出一種新的接收方式，此方法有別於傳統UF-OFDM在接收端只使用偶數頻段之訊號，而是將被視為干擾的奇數頻段訊號一起列入解調，以此來增加接收端的分集增益(Diversity gain)，並使得系統表現提升。模擬結果說明提出之新型接收方式能夠顯著的改善錯誤率(Bit Error Rate, BER)，在可加性高斯白雜訊(Additive White Gaussian Noise, AWGN)通道能提供相較傳統方式3dB的訊雜比增益(Signal-to-noise ratio gain)，且在頻率選擇性通道(Frequency selective channels)可以達到超過3dB的增益表現。然而為了進一步緩解加入奇數頻段訊號造成的計算負擔，我們提出一種基於每個子帶(sub-band)平行處理的低複雜度接收架構，透過先行對接收到之偶數頻段的訊號做粗略估計，便可以用其來減少子帶間的干擾，進一步實現每個子帶分開處理的低複雜度架構。除了模擬之外，我們也將上述的概念結合光載射頻(Radio-over-fiber, RoF)的毫米波多用戶無線電存取系統，並用實驗證明奇數頻段確實也包含有用的資訊，同時能夠在降低複雜度的要求下完整的利用接收之訊號能量，以符合5G大量低功耗設備通訊的情境。

This paper proposes a novel receiver for universal filtered multicarrier (UFMC). Unlike conventional receivers of UFMC, which focus on even subcarriers, the proposed receiver introduced disrupted odd subcarriers with even ones to decode the source data, thus exploiting the overall subcarriers and getting additional diversity gain. Simulation results show that the proposed receiver can significantly improve the bit error rate. The exploiting method provides a 3 dB signal-to-noise ratio gain compared to the conventional receiver through the additive white Gaussian noise channel. The performance gain can reach more than 3 dB in frequency-selective channels. However, to overcome the computation issue from additional odd subcarriers, we design a low-complexity detection approach based on parallel processing. Specifically, the transmitted data of each sub-band is coarsely estimated by even components of the received signal, then the interference between blocks is discarded. Finally, a complexity-reduced receiver is realized by decoding the out-of-band punctured data separately. Besides the simulation work, this paper experimentally demonstrated the advanced UFMC receiver in a multi-user millimeter (MMW) wave radio access system with radio-over-fiber (RoF). The experiment result indicates that odd channels also contain information on the transmitted data. Moreover, the proposed receiver can fully utilize the received power while easing the heavy computation burden, which is suitable for energy consumption issue in 5G communication systems.

[1] Ravi Teja Kamurthi and Shakti Raj chopra, “Review of UFMC Technique in 5G” 2018 International Conference on Intelligent Circuits and Systems
[2] Tzi-Dar Chiueh and Pei-Yun Tsai, “OFDM Baseband Receiver Design for Wireless Communications”
[3] Lei Zhang, Pei Xiao, and Atta Quddus, “Cyclic Prefix-Based Universal Filtered Multicarrier System and Performance Analysis,” in IEEE SIGNAL PROCESSING LETTERS, VOL. 23, NO. 9, SEPTEMBER 2016
[4] Sherief S. Helwa, Michael Ibrahim and Salwa Elramly, “Universal Filtered Multi-Carrier Performance Analysis with Multipath fading Channels, ” in 2016 10th International Conference on Next Generation Mobile Applications, Security and Technologies
[5] Chaoyue Jin, Li Wei and Youyun Xu, “Universal Filtered OFDM Index Modulation System with Enhanced ICI compression, ” The 28th Wireless and Optical Communication Conference (WOCC 2019)
[6] Mengting Wu , Jian Dang , Zaichen Zhang , and Liang Wu, “An Advanced Receiver for Universal Filtered Multicarrier,” in IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 67, NO. 8, AUGUST 2018
[7] Tsui-Tsai Lin and Tung-Chou Chen, “Complexity-Reduced Receiver for Universal Filtered Multicarrier Systems,” in IEEE WIRELESS COMMUNICATIONS LETTERS, VOL. 8, NO. 6, DECEMBER 2019
[8] Christina Lim, Yizhuo Yang and Ampalavanapillai Nirmalathas, “Transport Schemes for Fiber-Wireless Technology: Transmission Performance and Energy Efficiency,” Photonics 2014, 1, 67-82; doi:10.3390/photonics1020067
[9] James Lowery, “Amplified-spontaneous noise limit of optical OFDM lightwave systems, ” 21 January 2008 / Vol. 16, No. 2 / OPTICS EXPRESS 862
[10] Y. P. Lin and S. M. Phoong, “BER minimized OFDM systems with channel independent precoders,” IEEE Trans. Signal Process., vol. 51, no. 9, pp. 2369–2380, Sep. 2003.,"
[11] Z. Liu, Y. Xin, and G. B. Giannakis, “Linear constellation precoding for OFDM with maximum multipath diversity and coding gains,” IEEE Trans. Commun., vol. 51, no. 3, pp. 416–427, Mar. 2003.