AFDM Goes Over the Air: Possibly the World's First Real-Time USPR Hardware Demonstrator of AFDM

Welcome to my Google page. If you are interested in my research, please feel free to drop me an email. 

I am always looking for highly motivated students, visitors, and collaborators for the exciting communication 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 in UK or EU that we may jointly explore ([see my Essex page here]). If you have curiosity to the number 2357, please check here. 

I am very open to many forms of collaborations and firmly believe that modern academic life is more about how to engage with, energize and inspire a large number of scholars and engineers to meet ever-growing new challenges. 

Media Reports: 

• Essex 6G Lab Showcases Visionary Research from Colchester to ICC2026 by Essex Weekly.

• Essex's 6G Lab Showcases Research on The World Stage by Essex Weekly. 

• Boosting Wireless Efficiency with OFDM and SCMA by the EPSRC Communication Hub TITAN. 

• Awards celebrate amazing strengths of Essex research on my 2024 Outstanding Mid-Career Researcher Award by the Faculty of Science and Health, the University of Essex, as part of the celebration for the 60th anniversary of Essex. Another link on the Sixty Stories. 

• Building the Internet of Things for an Interconnected World by Futurum for my SCMA research. 

Research Interests:

My research lies in the interplay of coding, signal processing, and communications. I am extremely interested in attacking research problems that arise in practical communication and/or signal processing scenarios and in closing the gap between theoretical bounds and the achievable in hands-on implementations. At this stage, I am specifically interested in the following topics.

• New waveforms (e.g., AFDM) for resilient and scalable 6G systems and beyond; 

• Code-domain NOMA, e.g., sparse code multiple access (SCMA);

• Ultra-reliable and low-latency communications (URLLC), e.g., sparse vector coding (SVC);

• 6G V2X communications (e.g., in high mobility environments or hybrid VLC/RF V2X);

• Non-Terrestrial Networks (NTN) and its integration with Terrestrial Networks (TN);

• Integrated sensing, localization, and communications for 6G;

• Sequences and Their Applications;

• Advanced Error correction codes (e.g., LDPC, Turbo, Polar, RS+BCH);

• Iterative receiver design and graph-based inference;

• Detection and estimation (e.g., blind detection/estimation); 

• Communications for infrastructureless networks;

• AI and machine learning for enhanced communications and networking;

• Proof-of-concept hardware prototyping of wireless systems. 

Research Highlights: 

So far, I have made a series of original contributions to waveforms, sequences, and multiple access. Some selected publications on these topics are highlighted below: 

Waveforms:

1. Q. Luo, Z. Liu, L. Musavian, Q. Peng, and P. Xiao, "Frame-Based AFDM-ISAC Waveform Design With Chirp-Enabled Pulse Compression," IEEE Journal of Selected Topics in Signal Processing, June 2026, Accepted for publication. [PDF]

2. Z. Sui, Z. Liu, L. Musavian, Y. L. Guan, L.-L. Yang, and L. Hanzo, "MIMO-AFDM Outperforms MIMO-OFDM in the Face of Hardware Impairments," IEEE Transactions on Communications, May 2026, Accepted for publication. [PDF] [LinkedIn Advertising to this work] 

3. Q. Yi, Z. Liu, L. Musavian, and Z. Sui, "Non-Orthognal Affine Frequency Division Multiplexing for Spectrally Efficient High-Mobility Communications," IEEE Transactions on Wireless Communications, vol. 25, pp. 15758-15774, April 2026. [PDF] [LinkedIn Advertising to this work]

4. Z. Sui, Z. Liu, L. Musavian, L.-L. Yang, and L. Hanzo, "Generalized Spatial Modualtion Aided Affine Frequency Division Multiplexing," IEEE Transactions on Wireless Communications, vol. 25, pp. 4658-4673, October 2025. [PDF] [LinkedIn Advertising to this work]

5. X. Li, Z. Liu, Z. Zhou, and P. Fan, "Matched Filtering-Based Channel Estimation for AFDM Systems in Doubly Selective Channels," IEEE Transactions on Wireless Communications, vol. 25, pp. 15597-15610, Apr. 2026. [PDF]

6. C. Bai, P. Fan, Z. Zhou, and Z. Liu, "Orthogonal Chirp Delay-Dopper Division Multiplexing (CDDM) Modulation for High Mobility Communications," IEEE Transactions on Wireless Communications, vol. 25, pp. 8277-8291, Dec. 2025. [PDF]

7. Q. Luo, J. Zhu, Z. Liu, Y. Tang, P. Xiao, G. Chen, and J. Shi, "Joint Sparse Graph for Enhanced MIMO-AFDM Receiver Design," IEEE Transactions on Wireless Communications, vol. 25, pp. 3272-3286, September 2025. [PDF]

8. Y. Huang, P. Yang, Z. Liu, Y. Xiao, and T. Quek, "An Adaptive MDS-Coded OFDM Waveform for Low-Altitude ISAC: Design and Optimization," IEEE Journal on Selected Areas in Communications, vol. 44, pp. 531-544, September 2025

9. X. Li, P. Fan, Q. Wang, and Z. Liu, "Grid Evolution for Doubly Fractional Channel Estimation in OTFS Systems," IEEE Transactions on Vehicular Technology, vol. 74, no. 2, pp. 3486-3490, Feb. 2025.

10. Y. Huang, S. Hu, S. Ma, Z. Liu, and M. Xiao, ``Designing Low-PAPR Waveform for OFDM-based RadCom Systems," IEEE Transactions on Wireless Communiations, vol. 21, no. 9, pp. 6979-6993, Sep. 2022. [PDF] Note: A highly cited research paper on OFDM-ISAC waveform design with low PAPR. 

11. Z. Liu, P. Xiao, and S. Hu, "Low-PAPR Preamble Design for FBMC Systems," IEEE Transactions on Vehicular Technology, vol. 68, no. 8, pp. 7869-7876, Aug. 2019. PDF Note: This paper showed that Golay complementary sequences are extremely useful for low-PAPR preamble design in FBMC systems. 

12. Z. Liu, Y. L. Guan, and C.-C. Chui, "CPM Training Waveforms With Autocorrelation Sidelobes Close To Zero," IEEE Transactions on Vehicular Technology, vol. 67, no. 11, pp. 11269-11273, Nov. 2018. PDF Note: To the best of my knowledge, this is the first work in the literature on CPM training waveform design. 

Sequences: 

1. X. Peng, C. Wu, Z. Liu, C. Li, J. Zhang, X. Li, and P. Fan, "Zak-Transform-Induced Optimal Sequences and Their Applications in OTFS," IEEE Transactions on Communications, vol. 74, pp. 6008-6024, Jan. 2026. [PDF] [MATLAB Code] [Note]: A systematic study on optimal design of multiple sets of polyphase sequences over delay-Doppler domain (associated to Zak Transform). We showed that the proposed sequences can be directly applied as preamble sequences in OTFS systems. 

2. L. Meng, Y. L. Guan, Y. Ge, Z. Liu, and P. Fan, "Generalized Arlery-Tan-Rabaste-Levenshtein Lower Bounds on Ambiguity Function and Their Asymptotic Achievability,"  IEEE Transactions on Information Theory, vol. 71, no. 7, pp. 5744-5754, Jul. 2025. [PDF] [Note]: We derived the generalized Levenshtein bound for sequences with low ambiguity sidelobes. The core idea is to introduce to two weight vectors: one for the time delay and the other for the Doppler shift. 

3. L. Meng, Y. L. Guan, Y. Ge, and Z. Liu, ``Flag Sequence Set Design for Low-Complexity Delay-Doppler Estimation," IEEE Transactions on Vehicular Technology, vol. 74, no. 8, pp. 12131-12147, Aug. 2025. [PDF] [Flag Sequence Example] [Note]: We designed Flag sequences with curtain-peak ambiguity properties for lightweight delay-Doppler estimation in ISAC systems. 

4. L. Tian, X. Song, Z. Liu, and Y. Li, ``Asymptotically Optimal Sequence Sets with Low/Zero Ambiguity Zone Properties," IEEE Transactions on Information Theory, vol. 71, no. 6, pp. 4785-4796, Jun. 2025. [PDF].

5. P. Sarkar, C. Li, S. Majhi, and Z. Liu, "New Correlation Bound and Construction of Quasi-Complementary Sequence Sets," IEEE Transactions on Information Theory, vol. 70, no. 3, pp. 2201-2223, Mar. 2024. [PDF]

6. Z. Ye, Z. Zhou, Z. Liu, X. Tang, and P. Fan, ``New Spectrally Constrained Sequence Sets with Optimal Periodic Cross-Correlation," IEEE Transactions on Information Theory, vol. 69, no. 1, pp. 610-625, January 2023. [PDF]

7. Z. Ye, Z. Zhou, P. Fan, Z. Liu, X. Lei, and X. Tang, ``Low Ambiguity Zone: Theoretical Bounds and Doppler-Resilient Sequence Design in Integrated Sensing and Communication Systems," IEEE Journal on Selected Areas in Communications Special Issue on Integrated Sensing and Communications, vol. 40, no. 6, pp. 1809-1822, June 2022. [PDF] [Note]: A systematic study on Doppler-resilient sequences with low ambiguity zone.

8. Z. Liu, P. Yang, Y. L. Guan, and P. Xiao, "Cross Z-Complementary Pairs (CZCPs) for Optimal Training in Spatial Modulation Over Frequency Selective Channels," IEEE Transactions on Signal Processing, vol. 68, pp. 1529-1543, Feb. 2020. PDF [Matlab Code for Fig. 6]. Note: The first research paper on training sequence design for spatial modulation systems over frequency selective channels. It proposed a brand-new sequence pair concept that considers the crosscorrelation between the two constituent sequences. 

9. Z. Liu, Y. L. Guan, U. Parampalli, and S. Hu, “Spectrally-Constrained Sequences: Bounds and Constructions,” IEEE Transactions on Information Theory, vol. 64, no. 4, pp. 2571-2582, April 2018. [pdf] Note: A fundamental study on the correlation bounds and optimal contructions of spectrally-constrained sequences which play an important role in modern wireless systems (e.g., cognitive radio/radar, dynamic spectrum access) operating over non-continuous spectral bands. 

10. Z. Liu, Y. L. Guan and W. H. Mow, "Asymptotically Locally Optimal Weight Vector Design for a Tighter Correlation Lower Bound of Quasi-Complementary Sequence Sets," IEEE Transactions on Signal Processing, vol. 65, no. 12, pp. 3107-3119, June 2017. [pdf] Note: An analytical optimization approach on a challenging fractional quadratic programming problem associated to the generalized Levenshtein bound for quasi-complementary sequence sets. 

11. S. Hu, Z. Liu, Y. L. Guan, W. Xiong, G. Bi, and S. Li, "Sequence Design for Cognitive CDMA Communications under Arbitrary Spectrum Hole Constraint," IEEE Journal on Selected Areas in Communications.,  vol. 32, no. 11, pp. 1974-1986, Nov. 2014. [pdf] [MATLAB code for Figure 5]

12. Z. Liu, U. Parampalli, and Y. L. Guan, "Optimal Odd-length Binary Z-Complementary Pairs," IEEE Transactions on Information Theory, vol.  60,  no.  9, pp. 5768-5781, July 2014.[pdf] Note: The design theory of the optimal odd-length binary almost-complementary sequence pairs (the best alternative to the celebrated Golay complementary pairs for odd lengths), positively addressing the 2011 Li–Fan–Tang–Tu open problem.

13. Z. Liu, Y. L. Guan, and U. Parampalli, "New Complete Complementary Codes for the Peak-to-Mean Power Control in MC-CDMA,"  IEEE Transactions on Communications, vol. 62,  no. 3, pp. 1105-1113,  Mar. 2014. [pdf]  [Matlab code for Example 3]

14. Z. Liu, U. Parampalli, Y. L. Guan, and S. Boztas, "A New Weight Vector for a Tighter Levenshtein Bound on Aperiodic Correlation," IEEE Transactions on Information Theory, vol. 61, no. 2, pp. 1356-1366, Feb. 2014. [pdf] Note: A new weight vector that positively settles an open problem left by Vladimir Levenshtein (Russian coding theorist) in 1999 on the tightening of aperiodic correlation lower bounds of binary sequence sets.

15. Z. Liu, Y. L. Guan, and W. H. Mow, "A Tighter Correlation Lower Bound for Quasi-Complementary Sequence Sets," IEEE Transactions on Information Theory, vol. 60, no. 1, pp. 388-396, Jan. 2014. [pdf] Note: The first generalized Levenshtein bound for quasi-complementary sequence sets which is about $\sqrt{2}$ tighter than the corresponding Welch bound.

16. Z. Liu, Y. Li, and Y. L. Guan, "New Constructions of General QAM Golay Complementary Sequences," IEEE Transactions on Information Theory, vol. 59, no. 11, pp. 7684-7692, Nov. 2013. [pdf] Note: This paper developed generalized $4^q$-QAM Golay complementary sequences using selected Gaussian integer pairs, settling an open problem in the field on the mystery of certain 64-QAM Golay complemenatry sequences obtained through computer search. 

Multiple Access: 

1. M. Priyadarsini, Z. Liu, K. Deka, S. K. Sahoo, and S. Sharma, "Hybrid Rate-Splitting and Sparse Code Multiple Access (RS-SCMA): Design and Performance," IEEE Transactions on Communications, April, Accepted for publication. [PDF]. [MATLAB Code] [LinkedIn Advertising to this work] Note: We made the first step towards a novel concept "Universal Multiple Access (UMA)" which was first coined by Professor Bruno Clerckx in their 2024 paper “Multiple Access Techniques for Intelligent and Multifunctional 6G: Tutorial, Survey and Outlook” published in Proceedings of IEEE. 

2. Q. Luo, P. Xiao, Z. Liu, Z. Wan, N. Thomos, Z. Gao, and Z. He, ``AFDM-SCMA: A promising waveform for massive connectivity over high mobility channels," IEEE Transactions on Wireless Communications, vol. 23, no. 10, pp. 14421-14436, Oct. 2024. [PDF] Note: To the best of my knowledge, this is the first work on AFDM assisted code-domain multiple access systems. 

3. K. Lai, Z. Liu, J. Lei, G. Chen, and P. Xiao, "Sparse Code Multiple Access with Enhanced K-Repeition Scheme: Analysis and Design, " IEEE Transactions on Wireless Communications, vol 23, no. 6, pp. 5301-5315, Jun. 2024. [PDF] [Note]: We applied network coding (NC) to re-encode different packets (after channel coding and interleaving) or their fragments for enhanced NC aided K-repetition SCMA transmission. -- A novel HARQ design in code-domain NOMA systems. 

4. Q. Luo, Z. Liu, G. Chen, and P. Xiao, "Enhancing Signal Space Diversity for SCMA over Rayleigh Fading Channels," IEEE Transactions on Wireless Communications, vol. 23, no. 4, pp. 3676-3690, Apr. 2024. [PDF] [Codebook Examples]

5. Q. Luo, Z. Liu, G. Chen, P. Xiao, Y. Ma, and A. Maaref, "A Design of Low-Projection SCMA Codebooks for Ultra-Low Decoding Complexity in Downlink IoT Networks," IEEE Transactions on Wireless Communications, vol. 22, no. 10, pp. 6608-6623, Oct. 2023. [PDF] [Codebook Examples]

6. H. Wen, W. Yuan, Z. Liu, and S. Li, ``OTFS-SCMA: A Downlink NOMA Scheme for Massive Connectivity in High Mobility Channels," IEEE Transactions on Wireless Communications, vol. 22, no 9, pp. 5770-5784, Sep. 2023. [PDF]

7. H. Wen, Z. Liu, Q. Luo, C. Shi, and P. Xiao, ``Designing Enhanced Multi-Dimensional Constellations for Code-Domain NOMA," IEEE Wireless Communications Letters, vol. 11, no. 10, pp. 2130-2134, Oct. 2022. [PDF] [Multi-Dimensional Constellation Examples] Note: We pioneered the multi-dimensional constellation design with both large minimum Euclidean distance and minimum product distance. 

8. S. Chaturvedi, Z. Liu, V. Bohara, A. Srivastawa, and P. Xiao, ``A Tutorial on Decoding Techniques of Sparse Code Multiple Access," IEEE Access, vol. 10, May 2022. [PDF] Note: A systematic tutorial on SCMA codebook design and decoding techniques. 

9. Z. Liu and L.-L. Yang, "Sparse or Dense: A Comparative Study of Code-Domain NOMA Systems," IEEE Transactions on Wireless Communications, vol. 20, no. 8, pp. 4768-4780, Aug. 2021. [PDF] Note: A highly cited research paper on code-domain NOMA with and without sparsity. 

10. Z. Liu, Y. L. Guan, and H. H. Chen, "Fractional-Delay-Resilient Receiver for Interference-Free MC-CDMA Communications Based on Complete Complementary Codes," IEEE Transactions on Wireless Communications, vol. 14, no. 3, pp. 1226-1236, Mar. 2015. [pdf] Note: A long standing open problem for complementary code aided multicarrier CDMA is that the sytem suffers from orthogonality loss in practical fractional-delay channels. A novel correlator-bank assisted receiver design was proposed for truly interference-free performance. The first design in the literature. 

Additionally, some selected publications on Coding Theory, V2X Communications, and AI/ML for Communications and Networking.

Coding Theory:

1. D. Zhang, Y. Yang, Z. Liu, S. Jia. K. Lee, and Z. Zhang, "Low Complexity Weight Flexible Decoding Schemes of Linear Block Code for 6G xURLLC," IEEE Transactions on Vehicular Technology, vol. 75, no. 4, pp. 6922-6927, April 2026. [PDF]

2. L. Deng, Z. Liu, Y. L. Guan, X. Liu, C. A. Aslam, X. Yu, and Z. Shi, "Perturbed Adaptive Belief Propagation Decoding for High-Density Parity-Check Codes," IEEE Transactions on Communications, vol. 69, no. 4, pp. 2065-2079, April 2021, [PDF] [Note]: We advocate the key decoding observation that some bits with large LLR magnitudes may have wrong signs. Perturbed ABP arises by allocating a few best decoding resources (having sparsified columns in the dynamic parity check matrix) to those ill-conditioned bits. That explains "perturbation" in this work. 

3. Md. Noor-A-Rahim, Z. Liu, Y. L. Guan, and L. Hanzo, "Finite-Length Performance Analysis of LDPC Coded Continuous Phase Modulation," IEEE Transactions on Vehicular Technology, vol. 69, no. 10, pp. 12277-12280, Oct. 2020. [PDF]

4. X.-B. Liu, Y. L. Guan, S. N. Koh, Z. Liu, and P. Wang, “Low Complexity Single-Channel Blind Separation of Co-Frequency Coded Signals,” IEEE Communications Letters, vol. 22, no. 5, pp. 990-993, May 2018. [Note]: An interesting work involving turbo processing of multi-user per-survivor processing and soft-input soft-output channel decoding. 

5. J. Guo, Z. Shi, Z. Liu, Z. Zhang, and Q. Liu, "Multi-CRC Polar Codes and Their Applications," IEEE Communications Letters, vol. 20, no. 2, pp. 212-215, Feb. 2016.

V2X Communications:

1. H. Huang, Z. Liu, H. Wang, W. Huang, C. Gu, Z. Hu, and Md. Noor-A-Rahim, "A Theoretical Framework on Real-Time Communication and Information Estimation in Ultra Large-Scale 6G C-V2X Networks," IEEE Transactions on Wireless Communications, vol. 25, pp. 17494-17508, May 2026. 

2. G. Singh, A. Srivastava, V. Bohara, Md Noor-A-Rahim, Z. Liu, and D. Pesch, "Towards 6G-V2X: Aggregated RF-VLC for ultra-reliable and low-latency autonomous driving," IEEE Communications Standards Magazine, vol. 8, no. 4, pp. 80-87, Dec. 2024. [PDF]

3. G. Singh, D. Gupta, V. Bohara, A. Srivastava, and Z. Liu, ``Exploring Cooperative NOMA Assisted Hybrid Visible Light and Radio Frequency for Enhanced Vehicular Message Dissemination at Road Intersections," Physical Communication, vol. 55, December 2022. [PDF]

4. Md. Noor-A-Rahim, Z. Liu, H. Lee, M. Omar Khyam, J. He, D. Pesch, K. Moessner, W. Saad, and H. V. Poor,``6G for Vehicle-to-Everything (V2X) Communications: Enabling Technologies, Challenges, and Opportunities," Proceedings of the IEEE, vol. 110, no. 6, pp. 712-734, June 2022. [PDF]

5. G. Singh, A. Srivastava, V. Bohara, Z. Liu, Md. Noor-A-Rahim, and G. Ghatak, ``Heteogeneous Visible Light and Radio Communication for Improving Safety Message Dissemination at Road Intersection, " IEEE Transactions on Intelligent Transportation Systems, vol. 23, no. 10, pp. 17607-17619, Oct. 2022. [PDF]

6. H. Bagheri, Md Noor-A-Rahim, Z. Liu, H. Lee, D. Pesch, K. Moessner, and P. Xiao, "5G NR-V2X: Towards Connected and Cooperative Autonomous Driving Vehicular Networking," IEEE Communications Standards Magazine, vol. 5, no. 1, pp. 48-54, Mar. 2021. [PDF]. 

7. Md. Noor-A-Rahim, Z. Liu, H. Lee, G. G. Md. Nawaz Ali, Dirk Pesch, Pei Xiao, "A Survey on Resource Allocation in Vehicular Networks," IEEE Transactions on Intelligent Transportation Systems, vol. 23, no. 2, pp. 701-721, Feb. 2022. [PDF] 

8. Md. Noor-A-Rahim, M. O. Khyam, G. G. Nawaz Ali, Z. Liu, D. Pesch, and P. H. Chong, "Reliable State Estimation of an Unmanned Aerial Vehicle over a Distributed Wireless IoT Network," IEEE Transactions on Reliability, vol. 68, no. 3, pp. 1061-1069, Sept. 2019.

9. H. Nguyen, M. Noor-A-Rahim, Z. Liu, D. Jamaludin, and Y. L. Guan, "A Semi-Empirical Performance Study of Two-Hop DSRC Message Relaying at Road Intersection," MDPI, pp. 1-15, Information 2018, 9, 147. [PDF]

AI/ML for Communications and Networking:

1. S. K. Siam, M. Y. Arafat, M. M. Alam, X. Zhu, P. Yang, Z. Liu, K. Guha, and Md. Noor-A-Rahim, "AI-Driven Multi-Tier Aerial Communication Networks: A Review of Routing, Computing, Handover, Resource Management, and Optimization Techniques," Artificial Intelligence Review, July 2026, Accepted for publication.

2. S. K. Siam, M. Y. Arafat, K. Guha, Z. Liu, E. Pardo, H. Shin, and Md. Noor-A-Rahim, "Federated Deep Reinforcement Learning for Joint Coverage and Connectivity in Cooperative UAV Networks for Emergency Communications," IEEE Internet of Things Journal, July 2026, Accepted for publication. 

3. R. Shao, J. Li, S. Li, and Z. Liu, "Deep Semantic-Aware SCMA Codebook Learning for Semantic Communication Systems," IEEE Wireless Communications Letters, June 2026, Accepted for publication. 

4. P. Yang, H. He, Y. Zhao, M. Xiao, Z. Liu, Y. Xiao, G. Wu, and T. Q. S. Quek, "Large Language Model Aided Integrated Sensing and Communications in Low-Altitude Economy," IEEE Network Magazine, vol. 40, no. 3, pp. 184-192, May 2026. 

5. J. Tang, F. Chen, J. Li, and Z. Liu, ``Learn to Schedule: Data Freshness-oriented Intelligent Scheduling in Industrial IoT," IEEE Transactions on Cognitive Communications and Networking, vol. 11, no. 11, pp. 505-518, Feb. 2025. [PDF]

6. E. Yu, J. Zhu, Q. Li, Z. Liu, H. Chen, S. Shamai, and H. V. Poor, "Deep Learning Assisted Multiuser MIMO Load Modulated Systems for Enhanced Downlink mmWave Communications," IEEE Transactions on Wireless Communications, vol. 23, pp. 7, pp. 6750-6764, Jul. 2024. [PDF]

7. K. Jiang, P. Yang, B. Zhang, Z. Liu, J. Fu, and S. Li, ``A Novel Extreme-Learning-Machine Aided Receiver Design for THz-SM with Hardware Imperfections," IEEE Communications Letters, vol. 26, no. 11, pp. 2606-2610, Nov. 2022. [PDF]

8. M. Liu, H. Zhang, Z. Liu, and N. Zhao, ``Attacking Spectrum Sensing with Adversarial Deep Learning in Cognitive Radio-Enabled Internet of Things," IEEE Transactions on Reliability, vol. 72, no. 2, pp. 431-444, Jun. 2023. [PDF]

9. Q. Luo, Z. Liu, G. Chen, Y. Ma, and P. Xiao, ``A Novel Multi-Task Learning Empowered Codebook Design for Downlink SCMA Networks," IEEE Wireless Communications Letters, vol. 11, no. 6, pp. 1268-1272, June 2022. [PDF]

10. M. Liu, Z. Liu, W. Lu, Y. Chen, X. Gao, and N. Zhao, "Distributed few-shot learning for intelligent recognition of communication jamming," IEEE Journal of Selected Topics in Signal Processing, vol. 16, no. 3, pp. 395-405, Apr. 2022. [PDF] 

11. M. Zhang, Z. Zhou, L. Li, Z. Liu, M. Yang, Y. Feng, "HpGAN: Sequence Search with Generative Adversarial Networks," IEEE Transactions on Neural Networks and Learning Systems, Accepted for Publication. [PDF]

12. W. Wu, S. Hu, D. Lin, and Z. Liu, "DSLN: Securing Internet of Things Through RF Fingerprint Recognition in Low-SNR Settings," IEEE Internet of Things Journal, vol. 9, no. 5, pp. 3838-3849, Mar. 2022.

13. Q. Luo, Z. Mheich, G. Chen, P. Xiao, and Z. Liu, ``Reinforcement Learning Aided Link Adaptation for Downlink NOMA Systems with Channel Imperfections," in WS-02: Next Generation Multiple Access (NGMA) for Future Wireless Communications at IEEE Wireless Communications and Networking Conference (WCNC), March 26 - 29, 2023 in Glasgow, Scotland. 

14. D. Wu, L. Deng, Z. Liu, Y. Zhang, and Y. Han, "RL Random Access for Delay-Constrained Heterogeneous Wireless Networks: A Two-User Case," in IEEE GLOBECOM 2021, December 7-11, Madrid, Spain. 

15. J. Li, J. Tang, and Z. Liu, ``Deep Reinforcement Learning for Data Freshness-oriented Scheduling in Industrial IoT," in the IEEE GLOBECOM'2022, December 4-8, Rio de Janeiro, Brazil.