Publications

Book

  1. X. Yu, C. Li, J. Zhang, and K. B. Letaief, Stochastic Geometry Analysis of Multi-Antenna Wireless Networks, Springer, 2019. [Book Website]

Journal Papers

  1. Z. Hao, Y. Fang, X. Yu, J. Xu, L. Qiu, L. Xu, and S. Cui, “Energy-efficient hybrid beamforming with dynamic on-off control for integrated sensing, communications, and powering,” submitted to IEEE Trans. Commun., Mar. 2024. [Paper]

  2. S. Liu, X. Yu, Z. Gao, J. Xu, D. W. K. Ng, and S. Cui, “Sensing-enhanced channel estimation for near-field XL-MIMO systems,” submitted to IEEE J. Sel. Areas Commun., Special Issue on Next Generation Advanced Transceiver Technologies, Mar. 2024. [Paper]

  3. H. He, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Cell-free massive MIMO detection: A distributed expectation propagation approach,” submitted to IEEE J. Sel. Areas Commun., Special Issue on Next Generation Advanced Transceiver Technologies, Mar. 2024. [Paper]

  4. W. Yu, H. He, X. Yu, S.H. Song, J. Zhang, R. D. Murch, and K. B. Letaief, “Bayes-optimal unsupervised learning for channel estimation in near-field holographic MIMO,” submitted to IEEE J. Sel. Topics Signal Process., Special Issue on Near-Field Signal Processing: Algorithms, Implementations and Applications, Dec. 2023. [Paper]

  5. Y. Mao, X. Yu, K. Huang, Y.-J. A. Zhang, and J. Zhang, “Green edge AI: A contemporary survey,” submitted to Proc. IEEE, Nov. 2023. [Paper]

  6. Y. Fang, S. Zhang, X. Li, X. Yu, J. Xu, and S. Cui, “Multi-IRS-enabled integrated sensing and communications,” IEEE Trans. Commun., to appear. [Paper]

  7. D. Xu, Y. Xu, X. Zhang, X. Yu, S.H. Song, and R. Schober, “Interference mitigation for network-Level ISAC: An optimization perspective,” IEEE Commun. Mag., to appear. [Paper]

  8. H. He, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Message passing meets graph neural networks: A new paradigm for massive MIMO systems,” IEEE Trans. Wireless Commun., to appear. [Paper]

  9. W. Yu, Y. Shen, H. He, X. Yu, S.H. Song, J. Zhang, K. B. Letaief, “An adaptive and robust deep earning framework for THz ultra-Massive MIMO channel estimation,” IEEE J. Sel. Topics Signal Process., Special Issue on Advanced Signal Processing for Terahertz Communications in 6G and Beyond Networks, vol. 17, no. 4, pp. 761-776, July 2023. [Paper]

  10. D. Xu, X. Yu, D. W. K. Ng, A. Schmeink, and R. Schober, “Robust and secure resource allocation for ISAC systems: A novel optimization framework for variable-length snapshots,” IEEE Trans. Commun., vol. 70, no. 12, pp. 8196-8214, Dec. 2022. [Paper]

  11. Y. Ma, Y. Shen, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Learn to communicate with neural calibration: Scalability and generalization,” IEEE Trans. Wireless Commun., vol. 21, no. 11, pp. 9947-9961, Nov. 2022. [Paper]

  12. X. Zhang, X. Yu, and S.H. Song, “Outage probability and finite-SNR DMT analysis for IRS-aided MIMO systems: How large IRSs need to be?” IEEE J. Sel. Topics Signal Process., Special Issue on Advanced Signal Processing for Reconfigurable Intelligent Surface-aided 6G Networks, vol. 16, no. 5, pp. 1070-1085, Aug. 2022. [Paper]

  13. C. Qi, Q. Liu, X. Yu, and G. Y. Li, “Hybrid precoding for mixture use of phase shifters and switches in mmWave massive MIMO,” IEEE Trans. Commun., May 2022, vol. 70, no. 6, pp. 4121-4133, June 2022. [Paper]

  14. T. Lin, X. Yu, Y. Zhu, and R. Schober, “Channel estimation for IRS-assisted millimeter-wave MIMO systems: Sparsity-inspired approaches,” IEEE Trans. Commun., vol. 70, no. 6, pp. 4078-4092, June 2022. [Paper]

  15. D. Xu, V. Jamali, X. Yu, D. W. K. Ng, and R. Schober, “Optimal resource allocation design for large IRS-assisted SWIPT systems: A scalable optimization framework,” IEEE Trans. Commun., vol. 70, no. 2, pp. 1423-1441, Feb. 2022. [Paper]

  16. Z. Wei, X. Yu, D. W. K. Ng, and R. Schober, “Resource allocation for simultaneous wireless information and power transfer systems: A tutorial overview,” Proc. IEEE, vol. 110, no. 1, pp. 127-149, Jan. 2022. (Invited Paper) [Paper]

  17. X. Yu, V. Jamali, D. Xu, D. W. K. Ng, and R. Schober, “Smart and reconfigurable wireless communications: From IRS modeling to algorithm design,” IEEE Wireless Commun., vol. 28, no. 6, pp. 118-125, Dec. 2021. [Paper]

  18. H. He, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Cell-free massive MIMO for 6G wireless communication networks,” J. Commun. Inf. Netw., vol. 6, no. 4, pp. 321-335, Dec. 2021. (Invited Paper) [Paper]

  19. X. Yu, D. Xu, D. W. K. Ng, and R. Schober, “IRS-assisted green communication systems: Provable convergence and robust optimization,” IEEE Trans. Commun., vol. 69, no. 9, pp. 6313-6329, Sept. 2021. [Paper]

  20. D. Xu, X. Yu, Y. Sun, D. W. K. Ng, and R. Schober, “Resource allocation for IRS-assisted full-duplex cognitive radio systems,” IEEE Trans. Commun., vol. 68, no. 12, pp. 7376-7394, Dec. 2020. [Paper]

  21. X. Yu, D. Xu, Y. Sun, D. W. K. Ng, and R. Schober, “Robust and secure wireless communications via intelligent reflecting surfaces,” IEEE J. Sel. Areas Commun., Special Issue on Wireless Networks Empowered by Reconfigurable Intelligent Surfaces, vol. 38, no. 11, pp. 2637-2652, Nov. 2020. (2023 IEEE Communications Society Leonard G. Abraham Prize) (ESI Highly Cited Paper) [Paper]

  22. J. Zhang, X. Yu, and K. B. Letaief, “Hybrid beamforming for 5G and beyond millimeter-wave systems: A holistic view,” IEEE Open J. Commun. Soc., vol. 1, pp. 77-91, Dec. 2019. (Invited Paper) [Paper]

  23. X. Yu, J. Zhang, and K. B. Letaief, “Doubling phase shifters for efficient hybrid precoding in millimeter-wave multiuser OFDM systems,” J. Commun. Inf. Netw., vol. 4, no. 2, pp. 51-67, July 2019. [Paper]

  24. X. Yu, C. Li, J. Zhang, M. Haenggi, and K. B. Letaief, “A unified framework for the tractable analysis of multi-antenna wireless networks,” IEEE Trans. Wireless Commun., vol. 17, no. 12, pp. 7965-7980, Dec. 2018. [Paper]

  25. X. Yu, J. Zhang, and K. B. Letaief, “A hardware-efficient analog network structure for hybrid precoding in millimeter wave systems,” IEEE J. Sel. Topics Signal Process., Special Issue on Hybrid Analog-Digital Signal Processing for Hardware-Efficient Large Scale Antenna Arrays, vol. 12, no. 2, pp. 282-297, May 2018. [Paper] [Codes]

  26. X. Yu, J. Zhang, M. Haenggi, and K. B. Letaief, “Coverage analysis for millimeter wave networks: The impact of directional antenna arrays,” IEEE J. Sel. Areas Commun., Special Issue on Millimeter Wave Communications for Future Mobile Networks, vol. 35, no. 7, pp. 1498-1512, July 2017. (ESI Highly Cited Paper) [Paper]

  27. X. Yu, J.-C. Shen, J. Zhang, and K. B. Letaief, “Alternating minimization algorithms for hybrid precoding in millimeter wave MIMO systems,” IEEE J. Sel. Topics Signal Process., Special Issue on Signal Processing for Millimeter Wave Wireless Communications, vol. 10, no. 3, pp. 485-500, Apr. 2016. (2018 IEEE Signal Processing Society Young Author Best Paper Award) (ESI Highly Cited Paper) (Top 25 downloaded article in 2019) [Paper] [Codes]

Conference Papers

  1. S. Liu, X. Yu, Z. Gao, and D. W. K. Ng, “DPSS-based codebook design for near-field XL-MIMO channel estimation,” accepted to IEEE Int. Conf. Commun. (ICC), Denver, CO, USA, June 2024.

  2. W. Yu, H. He, X. Yu, S.H. Song, J. Zhang, R. Murch, and K. B. Letaief, “Learning Bayes-optimal channel estimation for holographic MIMO in unknown EM environments,” accepted to IEEE Int. Conf. Commun. (ICC), Denver, CO, USA, June 2024.

  3. R. Cao, W. Yu, H. He, X. Yu, S.H. Song, J. Zhang, Y. Gong, and K. B. Letaief, “Newtonized near-field channel estimation for ultra-massive MIMO systems,” accepted to IEEE Wireless Commun. Netw. Conf. (WCNC), Dubai, UAE, Apr. 2024.

  4. Y. Ma, W. Yu, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Lightweight and flexible deep equilibrium learning for CSI feedback in FDD massive MIMO,” accepted to IEEE Int. Conf. Mach. Learn. Commun. Netw. (ICMLCN), Stockholm, Sweden, May 2024.

  5. D. Xu, D. Shao, X. Yu, D. W. K. Ng, and R. Schober, “Multi-objective optimization for active IRS-assisted communication systems,” in Proc. IEEE Int. Mediterranean Conf. Commun. Netw. (MeditCom), Dubrovnik, Croatia, Sept. 2023, pp. 340-345.

  6. D. Xu, A. Khalili, X. Yu, D. W. K. Ng, and R. Schober, “Integrated sensing and communication in distributed antenna networks,” in Proc. IEEE Int. Conf. Commun. Wkshps. (ICC Wkshps), Rome, Italy, May 2023, pp. 1457-1462.

  7. W. Yu, H. He, X. Yu, S.H. Song, J. Zhang, and K. B. Letaief, “Blind performance prediction for deep learning based ultra-massive MIMO channel estimation,” in Proc. IEEE Int. Conf. Commun. (ICC), Rome, Italy, May 2023, pp. 2613-2618.

  8. H. He, A. Kosasih, X. Yu, J. Zhang, S.H. Song, W. Hardjawana, and K. B. Letaief, “GNN-enhanced approximate message passing for massive/ultra-massive MIMO detection,” in Proc. IEEE Wireless Commun. Netw. Conf. (WCNC), Glasgow, Scotland, UK, Mar. 2023, pp. 1-6.

  9. W. Yu, Y. Shen, H. He, X. Yu, J. Zhang, and K. B. Letaief, “Hybrid far- and near-field channel estimation for THz ultra-massive MIMO via fixed point networks,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Rio de Janeiro, Brazil, Dec. 2022, pp. 5384-5389.

  10. Y. Ma, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Augmented deep unfolding for downlink beamforming in multi-cell massive MIMO with limited feedback,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Rio de Janeiro, Brazil, Dec. 2022, pp. 1721-1726.

  11. L. Xie, X. Yu, and S.H. Song, “Intelligent reflecting surface-assisted maneuvering target sensing: True velocity estimation,” in Proc. Int. Symp. Wireless Commun. Syst. (ISWCS), Hangzhou, China, Oct. 2022, pp. 1-6. (Invited Paper) [Paper]

  12. R. Cao, H. He, X. Yu, J. Zhang, S.H. Song, Y. Gong, and K. B. Letaief, “Belief propagation for near-field cooperative localization and tracking in 6G vehicular networks,” in Proc. IEEE Int. Mediterranean Conf. Commun. Netw. (MeditCom), Athens, Greece, Sept. 2022, pp. 160-165.

  13. Z. Qiao, Y. Shen, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Content-aware client selection for federated learning in wireless networks,” in Proc. IEEE Int. Mediterranean Conf. Commun. Netw. (MeditCom), Athens, Greece, Sept. 2022, pp. 49-54.

  14. X. Zhang, X. Yu, S.H. Song, and K. B. Letaief, “Large-scale IRS-aided MIMO over double-scattering channel: An asymptotic approach,” in Proc. IEEE Wireless Commun. Netw. Conf. (WCNC), Austin, TX, USA, Apr. 2022, pp. 2076-2081.

  15. H. He, H. Wang, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Distributed expectation propagation detection for cell-free massive MIMO,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Madrid, Spain, Dec. 2021, pp. 1-6.

  16. Y. Ma, Y. Shen, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “Neural calibration for scalable beamforming in FDD massive MIMO with implicit channel estimation,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Madrid, Spain, Dec. 2021, pp. 1-6.

  17. Q. Liu, C. Qi, X. Yu, and G. Y. Li, “MmWave MIMO hybrid precoding design using phase shifters and switches,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Madrid, Spain, Dec. 2021, pp. 1-6.

  18. D. Xu, X. Yu, D. W. K. Ng, and R. Schober, “Resource allocation for active IRS-assisted multiuser communication systems,” in Proc. Asilomar Conf. Signals, Systems, Computers, Pacific Grove, CA, USA, Nov. 2021, pp. 113-119. (Invited Paper) [Paper]

  19. D. Xu, X. Yu, V. Jamali, D. W. K. Ng, and R. Schober, “Resource allocation for large IRS-assisted SWIPT systems with non-linear energy harvesting model,” in Proc. IEEE Wireless Commun. Netw. Conf. (WCNC), Nanjing, China, Mar. 2021, pp. 1-7.

  20. Y. Ma, Y. Shen, X. Yu, J. Zhang, S.H. Song, and K. B. Letaief, “A low-complexity algorithmic framework for large-scale IRS-assisted wireless systems,” in Proc. IEEE Global Commun. Conf. Wkshps. (GLOBECOM Wkshps), Taiwan, Dec. 2020, pp. 1-6.

  21. X. Yu, D. Xu, D. W. K. Ng, and R. Schober, “Power-efficient resource allocation for multiuser MISO systems via intelligent reflecting surfaces,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Taiwan, Dec. 2020, pp. 1-6.

  22. T. Lin, X. Yu, Y. Zhu, and R. Schober, “Channel estimation for intelligent reflecting surface-assisted millimeter wave MIMO systems,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Taiwan, Dec. 2020, pp. 1-6.

  23. D. Xu, X. Yu, and R. Schober, “Resource allocation for intelligent reflecting surface-assisted cognitive radio networks,” in Proc. IEEE Int. Workshop Signal Process. Adv. Wireless Commun. (SPAWC), Atlanta, GA, USA, May 2020, pp. 1-5. (Invited Paper) [Paper]

  24. X. Yu, D. Xu, and R. Schober, “Optimal beamforming for MISO communications via intelligent reflecting surfaces,” in Proc. IEEE Int. Workshop Signal Process. Adv. Wireless Commun. (SPAWC), Atlanta, GA, USA, May 2020, pp. 1-5. (Invited Paper) [Paper]

  25. D. Xu, X. Yu, and R. Schober, “Resource allocation for secure IRS-assisted multiuser MISO systems,” in Proc. IEEE Global Commun. Conf. Wkshps. (GLOBECOM Wkshps), Waikoloa, HI, USA, Dec. 2019, pp. 1-6.

  26. X. Yu, D. Xu, and R. Schober, “Enabling secure wireless communications via intelligent reflecting surfaces,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Waikoloa, HI, USA, Dec. 2019, pp. 1-6. (Best Paper Award) (IEEE ComSoc Best Readings) [Paper]

  27. X. Yu, D. Xu, and R. Schober, “MISO wireless communication systems via intelligent reflecting surfaces,” in Proc. IEEE/CIC Int. Conf. Commun. China (ICCC), Changchun, China, Aug. 2019, pp. 735-740. (Invited Paper) [Paper]

  28. X. Yu, J. Zhang, R. Schober, and K. B. Letaief, “A tractable framework for coverage analysis of cellular-connected UAV networks,” in Proc. IEEE Int. Conf. Commun. Wkshps. (ICC Wkshps), Shanghai, China, May 2019, pp. 1-6.

  29. X. Yu, J. Zhang, and K. B. Letaief, “Hybrid precoding in millimeter wave systems: How many phase shifters are needed?” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Singapore, Dec. 2017, pp. 1-6. (Best Paper Award) [Paper]

  30. X. Yu, J. Zhang, and K. B. Letaief, “Partially-connected hybrid precoding in mm-wave systems with dynamic phase shifter networks,” in Proc. IEEE Int. Wkshp. Signal Process. Adv. Wireless Commun. (SPAWC), Sapporo, Japan, July 2017, pp. 129-133.

  31. X. Yu, C. Li, J. Zhang, and K. B. Letaief, “A tractable framework for performance analysis of dense multi-antenna networks,” in Proc. IEEE Int. Conf. Commun. (ICC), Paris, France, May 2017, pp. 1-6.

  32. X. Yu, J. Zhang, and K. B. Letaief, “Alternating minimization for hybrid precoding in multiuser OFDM mmWave systems,” in Proc. Asilomar Conf. Signals, Systems, Computers, Pacific Grove, CA, USA, Nov. 2016, pp. 1-5. (Invited Paper) [Paper]

  33. X. Yu, J. Zhang, and K. B. Letaief, “Coverage analysis for dense millimeter wave cellular networks: The impact of array size,” in Proc. IEEE Wireless Commun. Netw. Conf. (WCNC), Doha, Qatar, Apr. 2016, pp. 1-6.

  34. X. Yu, J.-C. Shen, J. Zhang, and K. B. Letaief, “Hybrid precoding design in millimeter wave MIMO systems: An alternating minimization approach,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), San Diego, CA, USA, Dec. 2015, pp. 1-6.