鐘嘉德特聘教授的個人資料 - Profile of Char-Dir Chung

鐘嘉德 Char-Dir Chung

國立臺灣大學電機工程學系 特聘教授
Distinguished Professor, Department of Electrical Engineering, National Taiwan University

主要研究領域:

通訊系統及理論，無線通訊，數位調變

Major Research Areas:

Communication System and Theory, Wireless Communications, Digital Modulation

研究領域摘要:

鐘嘉德教授長期針對矩形脈波OFDM及衍生訊號，發展頻域預編碼技術以實施全頻域旁帶抑制，已成功建立頻域域編碼理論體系、為OFDM及衍生訊號(如OFDMA、MC-CDMA、Constant-Envelope OFDM、SC-FDMA、OTFS、ATSM)建立基頻旁帶抑制技術。主要原理為將OFDM及衍生訊號的資料符元於頻域透過線性方式組合，以導入資料符元的關聯性，進而產生多載波訊號的頻譜緊密及旁帶衰落。於國際通訊理論學界首先提出頻域預編碼正交分頻多工(SP-OFDM)、頻域預編碼正交時頻間隔(SP-OTFS)等系統，詳細內容已以論文型式發表於IEEE Trans. Commun.、IEEE Trans. Wireless Commun、IEEE Trans. Veh. Technol..期刊論文共16篇及IEEE 會議論文逾18篇，並獲與日俱增的引用。其中，頻域預編碼OFDM系統除了可以套用現行的OFDM的標準系統規格，還可以提供非常快速的功率頻譜旁帶衰落，亦即可提供更高的頻譜效率。此外，對於相鄰頻帶的信號所造成的干擾，也獲致大幅度的降低，因此可改良OFDM於多重接取通訊應用，極具實用潛力。為了發揮在未來高移動通訊系統中頻譜預編碼的價值，鐘教授持續的投注心力於與頻譜預編碼相關的OTFS、OTSM、ATSM系統設計課題，其中包括：帶有相關性資料的頻譜預編碼、多重輸入多重輸出傳輸、多重接取通訊、封均值降低方法、訊號初始同步、整合感通、與隨機接取導航訊號偵測。鐘教授深信頻譜預編碼技術的導入，將有助於同時提升高移動通訊系統的功率效率及頻譜效率，而且可激發新穎的多載波通訊的研究方向。

Research Summary:

        In recent years, Prof. Char-Dir Chung has been fully devoted to the academice reseacrh on digital  modulation theories. By introducing correlation among data symbols in frequency domain, Prof. Chung has  proposed several spectrally-precoded multicarrier modulation schemes in OFDM, OFDMA, OTFS, SC-FDMA, multicarrier CDMA, constant-envelope OFDM, and ATSM systems. These schemes are important in that they not only reshape the power spectrum of the rectangularly pulsed multicarrier signal to exhibit very small power spectral sidelobes and thus high spectrum compactness, but also permit implementation and analysis with ease. Because of the desirable characteristic of high spectral compactness, these schemes are very promising for use in future broadband communications. In order to exploit the use of spectral precoding as a valuable element in future systems, Prof. Chung is progressively working toward the following advanced subjects regarding the interaction of spectral precoding with other important system functions in multicarrier communication systems. These issues include spectral precoding on correlated data, multiple-input multiple-output transmission, peak-to-average power ratio reduction, channel estimation, block decoding, multiple-access communication, initial synchronization, integrated sensing and communication, and random-access preamble detection. The studies in these lines of research will advance the knowledge of spectrally-precoded multicarrier modulations.

 

Photo of Char-Dir Chung

代表性著作 Selected Publication

  1. C.-D. Chung, M.-Z. Xu, and W.-C. Chen, “Initial time synchronization for OTFS,” IEEE Trans. Veh. Technol., vol. 73, no. 12, pp. 18769, Dec. 2024
  2. W.-C. Chen, C.-D. Chung, and P.-H. Wang, “Pre-equalized and spectrally precoded OFDM,” IEEE Trans. Veh. Technol., vol. 71, no. 7, pp. 7472, Jul. 2022
  3. C.-D. Chung and W.-C. Chen, “Preamble sequence design for spectral compactness and initial synchronization in OFDM,” IEEE Trans. Veh. Technol., vol. 67, no. 2, p. 1428, Feb. 2018
  4. C.-D. Chung and K.-W. Chen, “Spectrally precoded OFDM without guard insertion,” IEEE Trans. Veh. Technol., vol. 66, no. 1, pp. 107, Jan. 2017
  5. W.-C. Chen and C.-D. Chung, “Spectrally efficient OFDM pilot waveform for channel estimation,” IEEE Trans. Commun., vol. 65, no. 1, pp. 387, Jan. 2017
  6. W.-C. Chen and C.-D. Chung, “Spectral precoding for cyclic-prefixed OFDMA with interleaved subcarrier allocation,” IEEE Trans. Commun., vol. 61, no. 11, pp. 4616-4629, Nov. 2013
  7. C.-H. Tseng and C.-D. Chung, “Concatenated precoded OFDM for CFO effect mitigation,” IEEE Trans. Veh. Technol., vol. 62, no. 6, pp. 2618-2632, Jul. 2013
  8. C.-D. Chung, W.-C. Chen and W.-L. Lin, “Realizable bandlimited DS-CDMA systems occupying Nyquist bandwidth,” IEEE Commun. Lett., vol. 16, no. 7, pp. 964-967, Jul. 2012
  9. C.-H. Huang and C.-D. Chung, “Differentially amplitude- and phase-encoded QAM for amplify-and-forward multiple relay system,” IEEE Trans. Veh. Technol., vol. 61, no. 5, pp. 2054-2066, Jun. 2012
  10. C.-D. Chung and W.-C. Chen, “Orthogonal multirate modulation,” IEEE Trans. Commun., vol. 60, no. 1, pp. 30-36, Jan. 2012
  11. C.-C. Lin, W.-C. Chen, and C.-D. Chung, “Spectral sidelobe decaying property of Walsh-Hadamard code in MC-CDMA systems,” IEEE Trans. Wireless Commun., vol. 10, no. 10, pp. 3151-3157, Oct. 2011
  12. C.-D. Chung, “Spectral precoding for constant-envelope OFDM,” IEEE Trans. Commun., vol. 58, pp. 555-567, Feb. 2010
  13. C.-D. Chung, “Spectral precoding for rectangularly pulsed OFDM,” IEEE Trans. Commun., vol. 56, no. 9, pp. 1498-1510, Sept. 2008
  14. 鐘嘉德, “Orthogonally-Multiplexed Orthogonal Amplitude Modulation Method,” US Patent No. 7158576B2, Jan. 2007
  15. C.-D. Chung, “Spectrally precoded OFDM,” IEEE Trans. Commun., vol. 54, no. 12, pp. 2173-2185, Dec. 2006
  16. C.-D. Chung and H.-S. Liaw, “Orthogonally multiplexed on-off-keyed amplitude and phase modulation families,” IEEE Trans. Wireless Commun., vol. 4, no. 1, pp. 288-299, Jan. 2005
  17. C.-D. Chung, “Coherent and differentially coherent detections of orthogonally -multiplexed orthogonal phase modulated signals,” IEEE Trans. Commun., vol. COM-51, no. 3, pp. 428-440, Mar. 2003
  18. C.-D. Chung, “Orthogonally-multiplexed orthogonal amplitude modulation family,” IEEE Trans. Commun., vol. COM-50, no. 3, pp. 415-428, Mar. 2002
  19. C.-D. Chung, “Differential detection of quadrature frequency/phase modulated signals,” IEEE Trans. Commun., vol. COM-47, no. 4, pp. 546-557, Apr. 1999