People

Dr Zilong Liu

Senior Lecturer
School of Computer Science and Electronic Engineering (CSEE)
Dr Zilong Liu
  • Email

  • Telephone

    +44 (0) 1206 874085

  • Location

    1NW.4.12, Colchester Campus

  • Academic support hours

    Thursday, 2-3pm. Zoom ID: 936 2953 7953. I would be very grateful if you could drop me an email before we meet.

Profile

Biography

Welcome to my Essex page. (More details of my research: https://sites.google.com/site/zilongliu2357.) I am always looking for highly motivated students, visitors, and collaborators. Please don't hesitate to drop me an email if you are interested in my research. If you have obtained (or close to) a PhD and wish to work with me as a postdoc researcher, there are a number of excellent Fellowships that we may explore together: Newton International Fellowships (2 years, THE ROYAL SOCIETY), University Research Fellowship (up to 8 years, THE ROYAL SOCIETY), Leverhume Trust Early Career Fellowship (3 years), EPSRC Postdoctoral Fellowships (3 years), MSCA Postdoc Fellowship (2~4 years), YUFE Postdoc Fellowship (3 years, under MSCA). My research lies in the interplay of coding, signal processing, and communications, with a major objective of bridging theory and practice as much as possible. One of my research aims is to understand the fundamental limits and bound-achieving design/processing approaches of various communication signals (e.g., codebooks/waveforms/sequences/channel codes). I am extremely interested in attacking research problems that arise in practical communication and/or signal processing scenarios. In recent years, I have developed a strong interest in advanced 6G V2X communication/sensing/localization technologies for future connected autonomous vehicles as well as machine learning for enhanced communications and networking. From January 2018 to November 2019, I was a Senior Research Fellow at the Institute for Communication Systems (ICS), Home of the 5G Innovation Centre (5GIC), University of Surrey, focusing on air-interface design of 5G networks and beyond (e.g., machine-type communications, URLLC, 5G NR, V2X, NOMA), working with Prof Pei Xiao and Prof Klaus Moessner (now with TU Chemnitz, Germany). During this period of time, I was a key researcher in the EPSRC project “New Air Interface Techniques for Future Massive Machine Communications" (EP/P03456X/1) and the EU-Taiwan project “Converged Wireless Access for Reliable 5G MTC for factories of future - Clear5G" (761745). Prior to my career in UK, I spent 9.5 years in the School of Electrical and Electronic Engineering, Nanyang Technological University (NTU), Singapore, first as a Research Associate (Jul. 2008 to Oct. 2014) and then a Research Fellow (November 2014 to Dec. 2018). During my work in NTU, I participated in a number of advanced projects on design and prototyping of ultra-reliable communication systems. I received my PhD from NTU in June 2014 with a thesis entitled ``Perfect- and Quasi- Complementary Sequences" , advised by Prof Guan Yong Liang. My PhD thesis, focusing on the fundamental limits, algebraic constructions, and applications of complementary sequences in wireless communications, has settled a few long-standing open problems in the field. These include: 1) An open problem left by Vladimir Levenshtein (Russian coding theorist) in 1999 on the tightening of aperiodic correlation lower bounds of binary sequence sets; 2) A generalized Levenshtein bound for quasi-complementary sequence sets which is tighter than the corresponding Welch bound; 3) The design theory of the optimal odd-length binary almost-complementary sequence pairs; 4) A novel correlator-bank assisted receiver design for truly interference-free multicarrier CDMA using complementary codes. These findings have been published in IEEE TRANSACTIONS ON INFORMATION THEORY, IEEE TRANSACTIONS ON SIGNAL PROCESSING, etc. I was a Visiting PhD student to University of Melbourne (May 2012 to Feb. 2013, hosted by Prof Udaya Parampalli) and Hong Kong University of Science and Technology (Jun 2013 to Jul. 2013, hosted by Prof Wai Ho Mow). I received my MSc Degree from Department of Electronic Engineering, Tsinghua University, Beijing, China, in Jul. 2007, with a thesis entitled "The Multistage Decoding Technique for DRM Receiver", advised by Prof Huazhong Yang (IEEE Fellow). Trained to become a Digital IC Design Engineer, I played with communication system simulation and ASIC implementation during the MSc period. In Jun. 2004, I received Bachelor Degree from School of Information and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, China. I am an IEEE Senior Member and an Associate Editor of IEEE Transactions on Vehicular Technology, IEEE Transactions on Neural Networks and Learning Systems, IEEE Wireless Communications Letters, IEEE Access, Frontiers in Communications and Networks, Frontiers in Signal Processing, as well as Advances in Mathematics of Communications (under American Institute of Mathematical Sciences). In 2019, I was endorsed to be an Exceptional Talent by The Royal Academy of Engineering. In 2019/2020/2021/2022, I was one of the World's Top 2% Scientists, according to reports from Stanford University. In August 2022, I was the Hosting General Co-Chair of the 10th IEEE International Workshop on Signal Design and its Applications in Communications (website: iwsda2022.github.io), a conference held at Essex. In January 2023, I was a Consultant to the National Institute of Information and Communication Technology (NIST), a Japanese Government organisation, on 6G V2X technologies for autonomous driving. In the UK, I am a member of the EPSRC Peer Review College and a Fellow of Higher Education Academy. Flexible, passionate, and determined, I am very open to engage with you to push forward the exciting forefront of the communication research.

Qualifications

  • PhD Nanyang Technological University (Singapore), (2014)

  • Master Degree Tsinghua University, (2007)

  • Bachelor Degree Huazhong University of Science and Technology, (2004)

Appointments

Other academic

  • Senior Research Fellow, 5G Innovation Centre, University of Surrey (5/1/2018 - 30/11/2019)

  • Research Fellow, School of EEE, Nanyang Technological University (1/11/2014 - 4/12/2018)

  • Research Associate, School of EEE, Nanyang Technological University (15/7/2008 - 31/10/2014)

Research and professional activities

Research interests

Error Correcting Codes (e.g., LDPC, Polar, Turbo, RS/BCH)

Signal Design (e.g., sequences/codebooks/waveforms) for Wireless Communications

Bayesian Inference & Iterative Receiver Design

Machine Learning for Communication Systems

Ultra-Reliable Low-Latency Communications (URLLC) for 5G and Beyond

Hardware Prototyping/Implementation of Wireless Communication Systems

Code-Domain Non-Orthogonal Multiple Access (NOMA) for Massive Connectivity

For example, sparse-code multiple access (SCMA) and traditional CDMA based overloaded multiuser systems.

Continuous Phase Modulation (CPM)

Research Allocation in Wireless Networks

Compressed Sensing for Communications

V2X Communications and Networks

DNA Coded Storage

ASIC Design of Communication and Signal Processing Algorithms

FMCW automotive radar

LoRa/LPWAN communications

Wireless postioning/localization

Teaching and supervision

Current teaching responsibilities

  • Team Project Challenge (CE101)

  • Telecommunication Principles (CE330)

Publications

Journal articles (106)

Gui, Y., Liu, Z., Yu, L., Li, C. and Fan, P., (2024). Novel Power-Imbalanced Dense Codebooks for Reliable Multiplexing in Nakagami Channels. IEEE Wireless Communications Letters. 13 (1), 19-23

Liu, H., Luo, Q., Liu, Z., Luo, S., Xiao, P. and Lin, R., (2024). BER Analysis of SCMA-OFDM Systems in the Presence of Carrier Frequency Offset. IEEE Communications Letters. 28 (1), 213-217

Chaturvedi, S., Bohara, VA., Liu, Z., Srivastava, A. and Xiao, P., (2024). Resource Management for Sum-rate Maximization in SCMA-Assisted UAV System. Vehicular Communications. 45, 100714-100714

Liu, Z., (2024). New Correlation Bound and Construction of Quasi-Complementary Sequence Sets. IEEE Transactions on Information Theory. 70 (3), 2201-2223

Liu, M., Zhang, H., Liu, Z. and Zhao, N., (2023). Attacking Spectrum Sensing With Adversarial Deep Learning in Cognitive Radio-Enabled Internet of Things. IEEE Transactions on Reliability. 72 (2), 431-444

Ye, Z., Zhou, Z., Liu, Z., Tang, X. and Fan, P., (2023). New Spectrally Constrained Sequence Sets With Optimal Periodic Cross-Correlation. IEEE Transactions on Information Theory. 69 (1), 610-625

Luo, Q., Liu, Z., Chen, G., Xiao, P., Ma, Y. and Maaref, A., (2023). A Design of Low-Projection SCMA Codebooks for Ultra-Low Decoding Complexity in Downlink IoT Networks. IEEE Transactions on Wireless Communications. 22 (10), 6608-6623

Huang, Y., Yang, P., Zhang, B., Liu, Z. and Xiao, M., (2023). A Novel Maximum Distance Separable Coded OFDM-RIS for 6G Wireless Communications. IEEE Wireless Communications Letters. 12 (5), 927-931

Chaturvedi, S., Bohara, VA., Liu, Z. and Srivastava, A., (2023). Sum-Rate Maximization of IRS-Aided SCMA System. IEEE Transactions on Vehicular Technology. 72 (8), 11-11

Zhou, Y., Zhou, Z., Liu, Z., Yang, Y., Yang, P. and Fan, P., (2023). Symmetrical Z-Complementary Code Sets for Optimal Training in Generalized Spatial Modulation. Signal Processing. 208, 108990-108990

Luo, Q., Liu, Z., Chen, G. and Xiao, P., (2023). Enhancing Signal Space Diversity for SCMA Over Rayleigh Fading Channels. IEEE Transactions on Wireless Communications, 1-1

Lai, K., Liu, Z., Lei, J., Chen, G., Xiao, P. and Wen, L., (2023). Sparse Code Multiple Access with Enhanced K-Repetition Scheme: Analysis and Design. IEEE Transactions on Wireless Communications, 1-1

Zhao, Y-Q., Pai, C-Y., Huang, Z-M., Liu, Z. and Chen, C-Y., (2023). Two-Dimensional Golay Complementary Array Sets With Arbitrary Lengths for Omnidirectional MIMO Transmission. IEEE Transactions on Communications, 1-1

Yu, L., Qian, J., Gui, Y., Liu, Z., Xiao, P., Wang, Y. and Wang, Z., (2023). Uniform-Distributed Constellation Codebook Design for High-Capacity Visible Light Communications. IEEE Communications Letters. 27 (11), 2993-2997

Haifeng, W., Weijie, Y., Zilong, L., Shuangyang, L. and Liu, Z., (2023). OTFS-SCMA: A Downlink NOMA Scheme for Massive Connectivity in High Mobility Channels. IEEE Transactions on Wireless Communications. 22 (9), 5770-5784

Dong, J., Liu, Z. and Cheng, Y., (2023). Editorial: Advanced signal processing techniques in radiation detection and imaging. Frontiers in Physics. 11

Yu, E., Zhu, J., Li, Q., Liu, Z., Chen, H., Shamai (Shitz), S. and Poor, HV., (2023). Deep Learning Assisted Multiuser MIMO Load Modulated Systems for Enhanced Downlink mmWave Communications. IEEE Transactions on Wireless Communications, 1-1

Huang, Z-M., Hu, C., Liu, Z. and Chen, C-Y., (2023). On the Mates of Cross Z-Complementary Pairs for Training Sequence Design in Generalized Spatial Modulation. IEEE Access. 11, 145231-145237

Wu, W., Hu, S., Lin, D. and Liu, Z., (2022). DSLN: Securing Internet of Things Through RF Fingerprint Recognition in Low-SNR Settings. IEEE Internet of Things Journal. 9 (5), 3838-3849

Li, X., Gao, Z., Gui, Y., Liu, Z., Xiao, P. and Yu, L., (2022). Design of Power-Imbalanced SCMA Codebook. IEEE Transactions on Vehicular Technology. 71 (2), 2140-2145

Yao, X., Yang, P., Fu, J., Xiao, Y. and Liu, Z., (2022). A Hybrid Multi-Domain Index Modulation for Covert Communication. IEEE Wireless Communications Letters. 11 (1), 8-12

Gao, P., Liu, Z., Xiao, P., Foh, CH. and Zhang, J., (2022). Low-Complexity Channel Estimation and Multi-User Detection for Uplink Grant-Free NOMA Systems. IEEE Wireless Communications Letters. 11 (2), 263-267

Chai, L., Liu, Z., Xiao, P., Maaref, A. and Bai, L., (2022). An Improved EPA-Based Receiver Design for Uplink LDPC Coded SCMA System. IEEE Wireless Communications Letters. 11 (5), 947-951

He, J. and Liu, Z., (2022). 6G for Vehicle-to-Everything (V2X) Communications: Enabling Technologies, Challenges, and Opportunities. Proceedings of the Institute of Electrical and Electronics Engineers (IEEE). 110 (6), 712-734

Jiang, K., Yang, P., Liu, Z., Guan, YL. and Renzo, MD., (2022). Power Allocation-Aided Enhanced SM-OFDM: Closed-form Solutions and Experimental Results. IEEE Transactions on Vehicular Technology. 71 (2), 2146-2151

Chaturvedi, S., Anwar, DN., Bohara, VA., Srivastava, A. and Liu, Z., (2022). Low-Complexity Codebook Design for SCMA-Based Visible Light Communication. IEEE Open Journal of the Communications Society. 3, 106-118

Zhu, J., Li, Q., Liu, Z., Chen, H. and Poor, HV., (2022). Enhanced User Grouping and Power Allocation for Hybrid mmWave MIMO-NOMA Systems. IEEE Transactions on Wireless Communications. 21 (3), 2034-2050

Liu, M., Liu, Z., Lu, W., Chen, Y., Gao, X. and Zhao, N., (2022). Distributed Few-Shot Learning for Intelligent Recognition of Communication Jamming. IEEE Journal of Selected Topics in Signal Processing. 16 (3), 395-405

Ye, Z., Zhou, Z., Fan, P., Liu, Z., Lei, X. and Tang, X., (2022). Low Ambiguity Zone: Theoretical Bounds and Doppler-Resilient Sequence Design in Integrated Sensing and Communication Systems. IEEE Journal on Selected Areas in Communications. 40 (6), 1809-1822

Luo, Q., Wen, H., Chen, G., Liu, Z., Xiao, P., Ma, Y. and Maaref, A., (2022). A Novel Non-Coherent SCMA With Massive MIMO. IEEE Wireless Communications Letters. 11 (11), 2250-2254

Wen, H., Liu, Z., Luo, Q., Shi, C. and Xiao, P., (2022). Designing Enhanced Multidimensional Constellations for Code-Domain NOMA. IEEE Wireless Communications Letters. 11 (10), 2130-2134

Gao, P., Liu, Z., Xiao, P., Foh, CH. and Zhang, J., (2022). Low-Complexity Block Coordinate Descend Based Multiuser Detection for Uplink Grant-Free NOMA. IEEE Transactions on Vehicular Technology. 71 (9), 9532-9543

Singh, G., Gupta, D., Bohara, VA., Srivastava, A. and Liu, Z., (2022). Exploring cooperative NOMA assisted hybrid visible light and radio frequency for enhanced vehicular message dissemination at road intersections. Physical Communication. 55, 101899-101899

Jiang, K., Yang, P., Zhang, B., Liu, Z., Fu, J. and Li, S., (2022). A Novel Extreme-Learning-Machine Aided Receiver Design for THz-SM With Hardware Imperfections. IEEE Communications Letters. 26 (11), 2606-2610

Singh, G., Srivastava, A., Bohara, VA., Liu, Z., Noor-A-Rahim, M. and Ghatak, G., (2022). Heterogeneous Visible Light and Radio Communication for Improving Safety Message Dissemination at Road Intersection. IEEE Transactions on Intelligent Transportation Systems. 23 (10), 17607-17619

Huang, Y., Hu, S., Ma, S., Liu, Z. and Xiao, M., (2022). Designing Low-PAPR Waveform for OFDM-Based RadCom Systems. IEEE Transactions on Wireless Communications. 21 (9), 6979-6993

Li, J., Tang, J. and Liu, Z., (2022). On the Data Freshness for Industrial Internet of Things With Mobile-Edge Computing. IEEE Internet of Things Journal. 9 (15), 13542-13554

Luo, Q., Liu, Z., Chen, G., Ma, Y. and Xiao, P., (2022). A Novel Multitask Learning Empowered Codebook Design for Downlink SCMA Networks. IEEE Wireless Communications Letters. 11 (6), 1268-1272

Ma, J., Li, Q., Liu, Z., Du, L., Chen, H. and Ansari, N., (2022). Jamming Modulation: An Active Anti-Jamming Scheme. IEEE Transactions on Wireless Communications. 22 (4), 2730-2743

Chaturvedi, S., Liu, Z., Bohara, VA., Srivastava, A. and Xiao, P., (2022). A Tutorial on Decoding Techniques of Sparse Code Multiple Access. IEEE Access. 10, 58503-58524

Zeng, Q., Liu, Z. and Gradoni, G., (2022). Optimal Quasi-Orthogonal FH Sequences With Adaptive Array Receiver for Massive Connectivity in Asynchronous Multi-Cluster Networks. IEEE Transactions on Wireless Communications. 21 (8), 5730-5743

Singh, G., Srivastava, A., Bohara, VA. and Liu, Z., (2021). Downlink Performance of Optical Power Domain NOMA for Beyond 5G Enabled V2X Networks. IEEE Open Journal of Vehicular Technology. 2, 235-248

Luo, Q., Gao, P., Liu, Z., Xiao, L., Mheich, Z., Xiao, P. and Maaref, A., (2021). An Error Rate Comparison of Power Domain Non-orthogonal Multiple Access and Sparse Code Multiple Access. IEEE Open Journal of the Communications Society. 2, 500-511

Sarkar, P., Majhi, S. and Liu, Z., (2021). Pseudo-Boolean Functions for Optimal Z-Complementary Code Sets with Flexible Lengths. IEEE Signal Processing Letters. 28, 1350-1354

Deng, L., Liu, Z., Guan, YL., Liu, X., Aslam, CA., Yu, X. and Shi, Z., (2021). Perturbed Adaptive Belief Propagation Decoding for High-Density Parity-Check Codes. IEEE Transactions on Communications. 69 (4), 2065-2079

Liu, Z. and Yang, L-L., (2021). Sparse or Dense: A Comparative Study of Code-Domain NOMA Systems. IEEE Transactions on Wireless Communications. 20 (8), 4768-4780

Zhang, M., Zhou, Z., Yang, M., Liu, Z. and Yang, Y., (2021). A hybrid algorithm for the search of long binary sequences with low aperiodic autocorrelations. Soft Computing. 25 (20), 12725-12744

Qian, L., Yang, P., Guan, YL., Liu, Z., Xiao, Y., Jiang, K. and Xiao, M., (2021). Multi-Dimensional Polarized Modulation for Land Mobile Satellite Communications. IEEE Transactions on Cognitive Communications and Networking. 7 (2), 383-397

Wu, S-W., Chen, C-Y. and Liu, Z., (2021). How to Construct Mutually Orthogonal Complementary Sets With Non-Power-of-Two Lengths?. IEEE Transactions on Information Theory. 67 (6), 3464-3472

Yu, L., Liu, Z., Wen, M., Cai, D., Dang, S., Wang, Y. and Xiao, P., (2021). Sparse Code Multiple Access for 6G Wireless Communication Networks: Recent Advances and Future Directions. IEEE Communications Standards Magazine. 5 (2), 92-99

Yao, X., Yang, P., Liu, Z., Xiao, M., Li, S. and Xiang, W., (2021). A Novel Hybrid Code-Domain Index Modulation Scheme. IEEE Communications Letters. 25 (10), 3403-3407

Lu, W., Si, P., Gao, Y., Han, H., Liu, Z., Wu, Y. and Gong, Y., (2021). Trajectory and Resource Optimization in OFDM-Based UAV-Powered IoT Network. IEEE Transactions on Green Communications and Networking. 5 (3), 1259-1270

Lu, W., Si, P., Lu, F., Li, B., Liu, Z., Hu, S. and Gong, Y., (2021). Resource and trajectory optimization in UAV-powered wireless communication system. Science China Information Sciences. 64 (4)

Bagheri, H., Noor-A-Rahim, M., Liu, Z., Lee, H., Pesch, D., Moessner, K. and Xiao, P., (2021). 5G NR-V2X: Toward Connected and Cooperative Autonomous Driving. IEEE Communications Standards Magazine. 5 (1), 48-54

Zhang, M., Zhou, Z., Li, L., Liu, Z., Yang, M. and Feng, Y., (2021). HpGAN: Sequence Search With Generative Adversarial Networks.. IEEE Transactions on Neural Networks and Learning Systems. 34 (8), 4944-4956

Xiao, L., Xiao, P., Liu, Z., Yu, W., Haas, H. and Hanzo, L., (2020). A Compressive Sensing Assisted Massive SM-VBLAST System: Error Probability and Capacity Analysis. IEEE Transactions on Wireless Communications. 19 (3), 1990-2005

Jiang, K., Liu, Z., Yang, P., Xiao, Y. and Li, S., (2020). An Experimental Investigation of Enhanced SM-OFDM Over Indoor Rician Multipath Channels. IEEE Transactions on Vehicular Technology. 69 (2), 2291-2295

Anand, K., Guan, YL., Liu, X., Liu, Z., Yang, Y., Zhou, Z., Fan, P. and Gunawan, E., (2020). Pilot Design for Enhanced Channel Estimation in Doubly Selective Channels. IEEE Transactions on Vehicular Technology. 69 (2), 1679-1694

Liu, Z., Yang, P., Guan, YL. and Xiao, P., (2020). Cross Z-Complementary Pairs for Optimal Training in Spatial Modulation Over Frequency Selective Channels. IEEE Transactions on Signal Processing. 68, 1529-1543

Zhou, Y., Zhou, Z., Liu, Z., Fan, P. and Guan, YL., (2020). Low-PMEPR Preamble Sequence Design for Dynamic Spectrum Allocation in OFDMA Systems. IEEE Transactions on Communications. 68 (5), 2922-2933

Mheich, Z., Liu, Z., Xiao, P. and Maaref, A., (2020). Delayed Bit Interleaved Coded Sparse Code Multiple Access. IEEE Transactions on Vehicular Technology. 69 (7), 8018-8022

Das, S., Parampalli, U., Majhi, S., Liu, Z. and Budisin, S., (2020). New Optimal $Z$-Complementary Code Sets Based on Generalized Paraunitary Matrices. IEEE Transactions on Signal Processing. 68, 5546-5558

Noor-A-Rahim, M., Liu, Z., Lee, H., Ali, GGMN., Pesch, D. and Xiao, P., (2020). A Survey on Resource Allocation in Vehicular Networks. IEEE Transactions on Intelligent Transportation Systems. 23 (2), 701-721

Chu, Z., Hao, W., Xiao, P., Mi, D., Liu, Z., Khalily, M., Kelly, JR. and Feresidis, AP., (2020). Secrecy Rate Optimization for Intelligent Reflecting Surface Assisted MIMO System. IEEE Transactions on Information Forensics and Security. 16, 1655-1669

Lu, W., Si, P., Liu, X., Li, B., Liu, Z., Zhao, N. and Wu, Y., (2020). OFDM based bidirectional multi-relay SWIPT strategy for 6G IoT networks. China Communications. 17 (12), 80-91

Noor-A-Rahim, M., Liu, Z., Guan, YL. and Hanzo, L., (2020). Finite-Length Performance Analysis of LDPC Coded Continuous Phase Modulation. IEEE Transactions on Vehicular Technology. 69 (10), 12277-12280

Adhikary, AR., Majhi, S., Liu, Z. and Guan, YL., (2020). New Sets of Optimal Odd-Length Binary Z-Complementary Pairs. IEEE Transactions on Information Theory. 66 (1), 669-678

Sarkar, P., Majhi, S. and Liu, Z., (2020). A Direct and Generalized Construction of Polyphase Complementary Sets With Low PMEPR and High Code-Rate for OFDM System. IEEE Transactions on Communications. 68 (10), 6245-6262

Wen, J., Zhou, Z., Liu, Z., Lai, M-J. and Tang, X., (2019). Sharp sufficient conditions for stable recovery of block sparse signals by block orthogonal matching pursuit. Applied and Computational Harmonic Analysis. 47 (3), 948-974

Liu, Z., Xiao, P. and Hu, S., (2019). Low-PAPR Preamble Design for FBMC systems. IEEE Transactions on Vehicular Technology. 68 (8), 7869-7876

Das, S., Majhi, S., Budisin, S. and Liu, Z., (2019). A New Construction Framework for Polyphase Complete Complementary Codes With Various Lengths. IEEE Transactions on Signal Processing. 67 (10), 2639-2648

Sarkar, P., Majhi, S. and Liu, Z., (2019). Optimal Z -Complementary Code Set From Generalized Reed-Muller Codes. IEEE Transactions on Communications. 67 (3), 1783-1796

Zhang, J., Hu, S., Liu, Z., Wang, P., Xiao, P. and Gao, Y., (2019). Real-Valued Orthogonal Sequences for Iterative Channel Estimation in MIMO-FBMC Systems. IEEE Access. 7, 68742-68751

Zeng, Q., Zhou, Z., Liu, X. and Liu, Z., (2019). Strong No-Hit-Zone Sequences for Improved Quasi-Orthogonal FHMA Systems: Sequence Design and Performance Analysis. IEEE Transactions on Communications. 67 (8), 5336-5345

Noor-A-Rahim, M., Khyam, MO., Ali, GGMN., Liu, Z., Pesch, D. and Chong, PHJ., (2019). Reliable State Estimation of an Unmanned Aerial Vehicle Over a Distributed Wireless IoT Network. IEEE Transactions on Reliability. 68 (3), 1061-1069

Han, S., Xu, X., Liu, Z., Xiao, P., Moessner, K., Tao, X. and Zhang, P., (2019). Energy-Efficient Short Packet Communications for Uplink NOMA-Based Massive MTC Networks. IEEE Transactions on Vehicular Technology. 68 (12), 12066-12078

Liu, Z., Guan, YL., Parampalli, U. and Hu, S., (2018). Spectrally-Constrained Sequences: Bounds and Constructions. IEEE Transactions on Information Theory. 64 (4), 2571-2582

Liu, Z., Guan, YL. and Chui, C-C., (2018). CPM Training Waveforms With Autocorrelation Sidelobes Close to Zero. IEEE Transactions on Vehicular Technology. 67 (11), 11269-11273

Das, S., Budisin, S., Majhi, S., Liu, Z. and Guan, YL., (2018). A Multiplier-Free Generator for Polyphase Complete Complementary Codes. IEEE Transactions on Signal Processing. 66 (5), 1184-1196

Gong, B., Gui, L., Luo, S., Guan, YL., Liu, Z. and Fan, P., (2018). Block Pilot Based Channel Estimation and High- Accuracy Signal Detection for GSM-OFDM Systems on High-Speed Railways. IEEE Transactions on Vehicular Technology. 67 (12), 11525-11536

Yang, P., Zhu, J., Liu, Z., Xiao, Y., Li, S. and Xiang, W., (2018). Unified Power Allocation for Receive Spatial Modulation Based on Approximate Optimization. IEEE Access. 6, 49450-49459

Nguyen, H., Noor-A-Rahim, M., Liu, Z., Jamaludin, D. and Guan, Y., (2018). A Semi-Empirical Performance Study of Two-Hop DSRC Message Relaying at Road Intersections. Information. 9 (6), 147-147

Das, S., Majhi, S. and Liu, Z., (2018). A Novel Class of Complete Complementary Codes and Their Applications for APU Matrices. IEEE Signal Processing Letters. 25 (9), 1300-1304

Adhikary, AR., Majhi, S., Liu, Z. and Guan, YL., (2018). New Sets of Even-Length Binary Z-Complementary Pairs With Asymptotic ZCZ Ratio of <inline-formula> <tex-math notation="LaTeX">$3/4$</tex-math> </inline-formula>. IEEE Signal Processing Letters. 25 (7), 970-973

Hu, S., Li, F., Guo, H., Wang, P., Bi, G., Gao, Y., Liu, Z. and Yu, B., (2018). TDCS-IDMA System for Cognitive Radio Networks With Cloud. IEEE Access. 6, 20520-20530

Hu, S., Luo, Q., Li, F., Liu, Z., Gao, Y. and Wu, J., (2018). Practical Implementation of Multi-User Transform Domain Communication System for Control Channels in Cloud-Based Cognitive Radio Networks. IEEE Access. 6, 17010-17021

Liu, X., Guan, YL., Koh, SN., Liu, Z. and Wang, P., (2018). Low-Complexity Single-Channel Blind Separation of Co-Frequency Coded Signals. IEEE Communications Letters. 22 (5), 990-993

Liu, Z., Guan, YL. and Mow, WH., (2017). Asymptotically Locally Optimal Weight Vector Design for a Tighter Correlation Lower Bound of Quasi-Complementary Sequence Sets. IEEE Transactions on Signal Processing. 65 (12), 3107-3119

Hu, S., Liu, Z., Guan, YL., Jin, C., Huang, Y. and Wu, J-M., (2017). Training Sequence Design for Efficient Channel Estimation in MIMO-FBMC Systems. IEEE Access. 5, 4747-4758

Yang, P., Guan, YL., Liu, XB. and Liu, Z., (2017). An Improved Hybrid Turbo Equalizer for Single Carrier Transmission with Impulsive Noise and ISI. IEEE Transactions on Vehicular Technology. 66 (11), 9852-9861

Li, X., Liu, Z., Guan, YL. and Fan, P., (2017). Two-Valued Periodic Complementary Sequences. IEEE Signal Processing Letters. 24 (9), 1270-1274

Yang, P., Xiao, Y., Guan, YL., Liu, Z., Li, S. and Xiang, W., (2017). Adaptive SM-MIMO for mmWave Communications With Reduced RF Chains. IEEE Journal on Selected Areas in Communications. 35 (7), 1472-1485

Yang, P., Xiao, Y., Guan, YL., Hari, KVS., Chockalingam, A., Sugiura, S., Haas, H., Di Renzo, M., Masouros, C., Liu, Z., Xiao, L., Li, S. and Hanzo, L., (2016). Single-Carrier SM-MIMO: A Promising Design for Broadband Large-Scale Antenna Systems. IEEE Communications Surveys & Tutorials. 18 (3), 1687-1716

Adhikary, AR., Liu, Z., Guan, YL., Majhi, S. and Budishin, SZ., (2016). Optimal Binary Periodic Almost-Complementary Pairs. IEEE Signal Processing Letters. 23 (12), 1816-1820

Guo, J., Shi, Z., Liu, Z., Zhang, Z. and Liu, Q., (2016). Multi-CRC Polar Codes and Their Applications. IEEE Communications Letters. 20 (2), 212-215

Liu, Z. and Guan, YL., (2016). 16-QAM Almost-Complementary Sequences With Low PMEPR. IEEE Transactions on Communications. 64 (2), 668-679

Liu, Z., Guan, YL. and Chen, H-H., (2015). Fractional-Delay-Resilient Receiver Design for Interference-Free MC-CDMA Communications Based on Complete Complementary Codes. IEEE Transactions on Wireless Communications. 14 (3), 1226-1236

Liu, Z., Guan, YL. and Mow, WH., (2014). A Tighter Correlation Lower Bound for Quasi-Complementary Sequence Sets. IEEE Transactions on Information Theory. 60 (1), 388-396

Liu, Z., Parampalli, U., Guan, YL. and Boztas, S., (2014). A New Weight Vector for a Tighter Levenshtein Bound on Aperiodic Correlation. IEEE Transactions on Information Theory. 60 (2), 1356-1366

Liu, Z., Parampalli, U. and Guan, YL., (2014). Optimal Odd-Length Binary Z-Complementary Pairs. IEEE Transactions on Information Theory. 60 (9), 5768-5781

Hu, S., Liu, Z., Guan, YL., Xiong, W., Bi, G. and Li, S., (2014). Sequence Design for Cognitive CDMA Communications under Arbitrary Spectrum Hole Constraint. IEEE Journal on Selected Areas in Communications. 32 (11), 1974-1986

Liu, Z., Guan, YL. and Parampalli, U., (2014). New Complete Complementary Codes for Peak-to-Mean Power Control in Multi-Carrier CDMA. IEEE Transactions on Communications. 62 (3), 1105-1113

Liu, Z., Parampalli, U. and Guan, YL., (2014). On Even-Period Binary Z-Complementary Pairs with Large ZCZs. IEEE Signal Processing Letters. 21 (3), 284-287

Liu, Z., Parampalli, U., Guan, YL. and Boztas, S., (2013). Constructions of Optimal and Near-Optimal Quasi-Complementary Sequence Sets from Singer Difference Sets. IEEE Wireless Communications Letters. 2 (5), 487-490

Liu, Z., Li, Y. and Guan, YL., (2013). New Constructions of General QAM Golay Complementary Sequences. IEEE Transactions on Information Theory. 59 (11), 7684-7692

Liu, ZL., Guan, YL., Ng, BC. and Chen, H-H., (2011). Correlation and Set Size Bounds of Complementary Sequences with Low Correlation Zone. IEEE Transactions on Communications. 59 (12), 3285-3289

Conferences (48)

Singh, G., Srivastava, A., Bohara, V. and Liu, Z., Comparison of PD-NOMA for RF and VLC based Vehicular Communication under Various Weather Conditions

Liu, Z., Guan, YL. and Hu, S., A New Algorithm for Cognitive Radio Sequences with Low Aperiodic Autocorrelations and Low PAPR

Wu, D., Deng, L., Liu, Z., Zhang, Y. and Han, Y., RL Random Access for Delay-Constrained Heterogeneous Wireless Networks: A Two-User Case

Chaturvedi, S., Bohara, VA., Liu, Z., Srivastava, A. and Xiao, P., Resource Allocation for Sum-Rate Maximization in Multi-UAV SCMA Networks

Luo, Q., Mheich, Z., Chen, G., Xiao, P. and Liu, Z., (2023). Reinforcement Learning Aided Link Adaptation for Downlink NOMA Systems With Channel Imperfections

Gao, P., Zhu, J., Chen, G., Liu, Z., Xiao, P. and Foh, CH., (2023). Efficient Multiuser Detection for Uplink Grant-Free NOMA via Weighted Block Coordinate Descend

Wang, Q., Ji, X., Qian, LP., Liu, Z., Du, X. and Kam, P-Y., (2023). MINE-based Geometric Constellation Shaping in AWGN Channel

Pai, C-Y., Liu, Z., Li, C. and Chen, C-Y., (2023). Sparse Complementary Pairs with Additional Aperiodic ZCZ Property

Chaturvedi, S., Bohara, VA., Liu, Z. and Srivastava, A., (2023). Trajectory Design for Sum-Rate Enhancement in UAV-SCMA System

Zhou, Y., Zhou, Z., Liu, Z., Yang, Y., Yang, P. and Fan, P., (2022). Symmetrical Z-Complementary Code Sets for Optimal Training in Generalized Spatial Modulation

Wen, H., Luo, Q., Yua, W., Liu, Z. and Xiao, P., (2022). OAMP for Low Complexity Detection in Large-Scale LDS Systems

Li, J., Tang, J. and Liu, Z., (2022). Minimizing Age of Information for Mobile Edge Computing Empowered Industrial Internet of Things

Deng, L., Guan, YL., Liu, Z., Shi, Z. and Zhang, Z., (2022). BCH-SPC based Cubic Turbo Product Coding

Meng, L., Guan, YL., Ge, Y. and Liu, Z., (2022). A Novel Design of Flag Sequences for Low-Complexity Delay-Doppler Estimation

Kazakov, P., Zheng, M. and Liu, Z., (2022). A Gear Construction of CRC Codes for Enhanced Polar Decoding

Das, S., Banerjee, A. and Liu, Z., (2022). New Family of Cross Z-Complementary Sequences With Large ZCZ Width

Pai, C-Y., Liu, Z., Zhao, Y-Q., Huang, Z-M. and Chen, C-Y., (2022). Designing Two-Dimensional Complete Complementary Codes for Omnidirectional Transmission in Massive MIMO Systems

Zhang, Y., Liu, Z., Xiao, P. and Guo, F., (2022). A Novel SCMA Codebook Design Method Based on Low Error Probability Criteria

Li, J., Tang, J. and Liu, Z., (2022). Deep Reinforcement Learning for Data Freshness-oriented Scheduling in Industrial IoT

Wu, D., Deng, L., Liu, Z., Zhang, Y. and Han, YS., (2021). Reinforcement Learning Random Access for Delay-Constrained Heterogeneous Wireless Networks: A Two-User Case

Zeng, Q., Liu, Z., Liu, X., Zhong, J. and Xiao, P., (2021). Frequency-Hopping Based SCMA for Massive Connectivity in Multi-Cell Networks

Ye, Z., Zhou, Z., Fan, P., Lei, X., Liu, Z. and Tang, X., (2021). Signal Design with Low/Zero Ambiguity Zone Characteristics for Joint Radar-Communication Systems

Mheich, Z., Hemadeh, IA., Liu, Z. and Xiao, P., (2020). Low-Complexity Expectation Propagation Detection for Uplink MIMO-SCMA Systems

Chen, H., Mi, D., Liu, Z., Xiao, P. and Tafazolli, R., (2020). Rate-Splitting for Overloaded Multigroup Multicast: Error Performance Evaluation

Liu, Z., Yang, P., Guan, YL. and Xiao, P., (2020). Cross Z-Complementary Pairs (CZCPs) for Optimal Training in Broadband Spatial Modulation Systems

Das, S., Parampalli, U., Majhi, S. and Liu, Z., (2020). Construction of New Optimal Z-Complementary Code Sets from Z-Paraunitary Matrices

Das, S., Parampalli, U., Majhi, S. and Liu, Z., (2019). Near-Optimal Zero Correlation Zone Sequence Sets from Paraunitary Matrices

Hu, S., Luo, Q., Zhang, J., Liu, Z., Huang, D. and Gao, Y., (2019). Practical Implementation of MIMO-FBMC System

Sarkar, P., Majhi, S. and Liu, Z., (2019). A Direct and Generalized Construction of Polyphase Complementary Set With Low PMEPR

Liu, Z., Xiao, P. and Mheich, Z., (2019). Power-Imbalanced Low-Density Signatures (LDS) From Eisenstein Numbers

Anand, K., Guan, YL., Liu, Z., Yang, Y., Zhou, Z., Fan, P. and Gunawan, E., (2019). Pilot design for channel estimation in Doubly Selective Channel

Hu, S., Zhang, J., Tang, J., Liu, Z., Xiao, P. and Gao, Y., (2018). Real-Valued Orthogonal Sequences for Ultra-Low Overhead Channel Estimation in MIMO-FBMC Systems

Liu, X-B., Guan, YL., Koh, SN., Ann Donny, TK. and Liu, Z., (2018). On the Performance of Single-Channel Source Separation of Two Co-Frequency PSK Signals with Carrier Frequency Offsets

Liu, Z., Guan, YL. and Mow, WH., (2017). A frequency-domain approach to tightening the generalized levenshtein bound

Liu, X-B., Guan, YL., Koh, SN., Liu, Z. and Wang, P., (2017). Single-channel blind separation of co-frequency PSK signals with unknown carrier frequency offsets

Adhikary, AR., Majhi, S., Liu, Z. and Guan, YL., (2017). New optimal binary Z-complementary pairs of odd lengths

Liu, T., Fan, P., Li, J., Yang, Y., Liu, Z. and Guan, YL., (2017). Sequence design for optimized ambiguity function and PAPR under arbitrary spectrum hole constraint

Wang, J., Fan, P., Yang, Y., Liu, Z. and Guan, YL., (2017). Doppler resilient Z-complementary waveforms from ESP sequences

Das, S., Majhi, S., Budisin, S., Liu, Z. and Guan, YL., (2017). A novel multiplier-free generator for complete complementary codes

Liu, Z., Guan, YL., Hu, S. and Parampalli, U., (2015). Optimal spectrally-constrained sequences

Hu, S., Liu, Z., Fang, S., Guan, YL., Wu, G. and Xiao, Y., (2015). ICI-Resilient Cognitive Radio Sequences for Transform Domain Communication Systems

Liu, Z., Guan, YL. and Parampalli, U., (2014). A new construction of zero correlation zone sequences from generalized reed-muller codes

Liu, Z., Guan, YL., Parampalli, U. and Boztas, S., (2013). Quadratic weight vector for tighter aperiodic Levenshtein bound

Liu, Z., Guan, YL. and Parampalli, U., (2013). On optimal binary Z-complementary pair of odd period

Liu, Z., Guan, YL. and Parampalli, U., (2013). 64-QAM complementary sets for high-rate OFDM transmissions

Liu, ZL. and Guan, YL., (2012). Meeting the Levenshtein bound with equality by weighted-correlation complementary set

Zi Long Liu, Yong Liang Guan and Wai Ho Mow, (2011). Improved lower bound for quasi-complementary sequence set

Long Liu, Z., Liang Guan, Y. and Chong Ng, B., (2009). A new class of Quadriphase Even-Shift Orthogonal Sequences

Grants and funding

2024

Glasswall AKT - December 2023

Innovate UK (formerly Technology Strategy Board)

Evolving Sequences for Beyond-5G Machine-Type Communications (SORT)

Engineering and Physical Sciences Research Council

2023

Training Sequence Design for Generalized Spatial Modulation Systems

The Royal Society

New Signal Design and Processing for Future Vehicular Communications (DRIVE)

Engineering and Physical Sciences Research Council

High Spectral Efficiency Minimal Interference NonOrthogonal Multiple Access Communication Signals

Nanyang Technological University Singapore

Contact

zilong.liu@essex.ac.uk
+44 (0) 1206 874085

Location:

1NW.4.12, Colchester Campus

Academic support hours:

Thursday, 2-3pm. Zoom ID: 936 2953 7953. I would be very grateful if you could drop me an email before we meet.