Publications

Book chapters

1. Economics of Fresh Data Trading
   M. Zhang, A. Arafa, J. Huang, and H. V. Poor
   Chapter 17 in Age of Information: Foundations and Applications, B. Zhou, W. Saad, H. Dhillon, N. Pappas and M. A. Abd-Elmagid, Eds., Cambridge University Press, Cambridge, UK, 2023, pp. 429–455.

2. Age Minimization in Energy Harvesting Communications
   A. Arafa, S. Fang, J. Yang, S. Ulukus, and H. V. Poor
   Chapter 8 in Green Communications for Energy-Efficient Wireless Systems and Networks, H. A. Suraweera, J. Yang, A. Zappone, J. S. Thompson, Eds., The Institution of Engineering and Technology (IET) Press, London, 2020, pp. 203–230.

Journal articles

Submitted/Preprints (Under Review):

1. Towards Understanding Federated Learning over Unreliable Networks
   C. Feng, A. Arafa, Z. Chen, M. Zhao, T. Q. S. Quek, and H. H. Yang

2. Delay Sensitive Hierarchical Federated Learning with Stochastic Local Updates (arXiv)
   A. Ali and A. Arafa

Published/To appear:

1. Timely Multi-Process Estimation Over Erasure Channels With and Without Feedback: Signal Independent Policies
   K. Banawan, A. Arafa, and K. G. Seddik
   IEEE Journal on Selected Areas in Information Theory, 4: 607–623, November 2023.

2. Short Blocklength Process Monitoring and Scheduling: Resolution and Data Freshness
   S. Roth, A. Arafa, A. Sezgin, and H. V. Poor
   IEEE Transactions on Wireless Communications, 21(7): 4669–4681, July 2022.

3. Spatiotemporal Analysis for Age of Information in Random Access Networks Under Last-Come First-Serve With Replacement Protocol
   H. H. Yang, A. Arafa, T. Q. S. Quek, and H. V. Poor
   IEEE Transactions on Wireless Communications, 21(4): 2813–2829, April 2022.

4. Timely Status Updating Over Erasure Channels Using an Energy Harvesting Sensor: Single and Multiple Sources
   A. Arafa, J. Yang, S. Ulukus, and H. V. Poor
   IEEE Transactions on Green Communications and Networking, 6(1): 6–19, March 2022.

5. Sample, Quantize and Encode: Timely Estimation Over Noisy Channels
   A. Arafa, K. Banawan, K. G. Seddik, and H. V. Poor
   IEEE Transactions on Communications, 69(10): 6485–6499, October 2021.

6. Optimizing Information Freshness in Wireless Networks: A Stochastic Geometry Approach
   H. H. Yang, A. Arafa, T. Q. S. Quek, and H. V. Poor
   IEEE Transactions on Mobile Computing, 20(6): 2269–2280, June 2021.

7. Optimal and Quantized Mechanism Design for Fresh Data Acquisition
   M. Zhang, A. Arafa, E. Wei, and R. A. Berry
   IEEE Journal on Selected Areas in Communications, 39(5): 1226–1239, May 2021.

8. Pricing Fresh Data
   M. Zhang, A. Arafa, J. Huang, and H. V. Poor
   IEEE Journal on Selected Areas in Communications, 39(5): 1211–1225, May 2021.

9. Age-Minimal Transmission for Energy Harvesting Sensors with Finite Batteries: Online Policies
   A. Arafa, J. Yang, S. Ulukus, and H. V. Poor
   IEEE Transactions on Information Theory, 66(1): 534–556, January 2020.

10. Secure Relaying in Non-Orthogonal Multiple Access: Trusted and Untrusted Scenarios
    A. Arafa, W. Shin, M. Vaezi, and H. V. Poor
    IEEE Transactions on Information Forensics and Security, 15(1): 210–221, January 2020.

11. Interplay Between NOMA and Other Emerging Technologies: A Survey
    M. Vaezi, G. Amarasuriya, Y. Liu, A. Arafa, F. Fang, and Z. Ding
    IEEE Transactions on Cognitive Communications and Networking, 5(4), 900–919, December 2019.

12. Timely Updates in Energy Harvesting Two-Hop Networks: Offline and Online Policies
    A. Arafa and S. Ulukus
    IEEE Transactions on Wireless Communications, 18(8): 4017–4030, August 2019.

13. Relay-Aided Secure Broadcasting for Visible Light Communications
    A. Arafa, E. Panayirci, and H. V. Poor
    IEEE Transactions on Communications, 67(6): 4227–4239, June 2019.

14. Delay Minimal Policies in Energy Harvesting Communication Systems
    A. Arafa, T. Tong, M. Fu, S. Ulukus, and W. Chen
    IEEE Transactions on Communications, 66(7):2918–2930, July 2018.

15. Online Fixed Fraction Policies in Energy Harvesting Communication Systems
    A. Arafa, A. Baknina, and S. Ulukus
    IEEE Transactions on Wireless Communications, 17(5):2975–2986, May 2018.

16. Mobile Energy Harvesting Nodes: Offline and Online Optimal Policies
    A. Arafa and S. Ulukus
    IEEE Transactions on Green Communications and Networking, 2(1):143–153, March 2018.

17. Energy Harvesting Two-Way Channels with Decoding and Processing Costs
    A. Arafa, A. Baknina, and S. Ulukus
    IEEE Transactions on Green Communications and Networking, 1(1):3–16, March 2017.

18. Optimal Policies for Wireless Networks with Energy Harvesting Transmitters and Receivers: Effects of Decoding Costs
    A. Arafa and S. Ulukus
    IEEE Journal on Selected Areas in Communications – Series on Green Communications and Networking, 33(12):2611–2625, December 2015.

19. A Feedback- Soft Sensing-Based Access Scheme for Cognitive Radio Networks
    A. Arafa, K. Seddik, A. Sultan, T. ElBatt, and A. El-Sherif
    IEEE Transactions on Wireless Communications, 12(7):3226–3237, July 2013.

Conference papers

1. Data Similarity-Based One-Shot Clustering for Multi-Task Hierarchical Federated Learning
   A. Ali and A. Arafa
   Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, California, October 2024.

2. Age of Information in Mobile Networks: Fundamental Limits and Tradeoffs
   M. Zhang, H. H. Yang, A. Arafa, and H. V. Poor
   ACM International Symposium on Theory, Algorithmic Foundations, and Protocol Design for Mobile Networks and Mobile Computing (MobiHoc), Athens, Greece, October 2024.

3. Age and Value of Information Optimization for Systems with Multi-Class Updates
   A. Arafa and Roy D. Yates
   IEEE International Conference on Communications (ICC), Denver, Colorado, June 2024.

4. Private Status Updating with Erasures: A Case for Retransmission Without Resampling
   A. Arafa and K. Banawan
   IEEE International Conference on Communications (ICC), Rome, Italy, May 2023.

5. Hierarchical Federated Learning in Delay Sensitive Communication Networks
   A. Ali and A. Arafa
   Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, California, October 2022.

6. Timely Multi-Process Estimation with Erasures
   K. Banawan, A. Arafa, and K. G. Seddik
   Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, California, October 2022.

7. Timely Updating with Intermittent Energy and Data for Multiple Sources over Erasure Channels
   C. Daniel Jr. and A. Arafa
   IEEE International Symposium on Wireless Communication Systems (ISWCS), Berlin, Germany, September 2021.
   

8. Timely Private Information Retrieval
   K. Banawan, A. Arafa, and S. Ulukus
   IEEE International Symposium on Information Theory (ISIT), Melbourne, Australia, July 2021.
   

9. Optimal Mechanism Design for Fresh Data Acquisition
   M. Zhang, A. Arafa, E. Wei, and R. A. Berry
   IEEE International Symposium on Information Theory (ISIT), Melbourne, Australia, July 2021.
   

10. Download Cost of Private Updating
    B. Herren, A. Arafa, and K. Banawan
    IEEE International Conference on Communications (ICC), Montreal, Canada, June 2021.

11. Timely Transmissions Using Optimized Variable Length Coding
    A. Arafa and R. D. Wesel
    IEEE Conference on Computer Communications (INFOCOM) Workshops, Vancouver, Canada, May 2021.

12. Age of Information in Random Access Networks: A Spatiotemporal Study
    H. H. Yang, A. Arafa, T. Q. S. Quek, and H. V. Poor
    IEEE Global Communications Conference (Globecom), Taipei, Taiwan, December 2020.

13. Timely Estimation Using Coded Quantized Samples
    A. Arafa, K. Banawan, K. G. Seddik, and H. V. Poor
    IEEE International Symposium on Information Theory (ISIT), Los Angeles, California, June 2020.

14. Remote Short Blocklength Process Monitoring: Trade-off Between Resolution and Data Freshness
    S. Roth, A. Arafa, H. V. Poor, and A. Sezgin
    IEEE International Conference on Communications (ICC), Dublin, Ireland, June 2020.

15. Age-Based Scheduling Policy for Federated Learning in Mobile Edge Networks
    H. H. Yang, A. Arafa, T. Q. S. Quek, and H. V. Poor
    IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Barcelona, Spain, May 2020.

16. On Timely Channel Coding with Hybrid ARQ
    A. Arafa, K. Banawan, K. G. Seddik, and H. V. Poor
    IEEE Global Communications Conference (Globecom), Waikoloa, Hawaii, December 2019.

17. Locally Adaptive Scheduling Policy for Optimizing Information Freshness in Wireless Networks
    H. H. Yang, A. Arafa, T. Q. S. Quek, and H. V. Poor
    IEEE Global Communications Conference (Globecom), Waikoloa, Hawaii, December 2019.

18. Timely Cloud Computing: Preemption and Waiting
    A. Arafa, R. D. Yates, and H. V. Poor
    Allerton Conference on Communication, Control, and Computing, Monticello, Illinois, September 2019.

19. Using Erasure Feedback for Online Timely Updating with an Energy Harvesting Sensor
    A. Arafa, J. Yang, S. Ulukus, and H. V. Poor
    IEEE International Symposium on Information Theory (ISIT), Paris, France, July 2019.

20. How to Price Fresh Data
    M. Zhang, A. Arafa, J. Huang, and H. V. Poor
    International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt), Avignon, France, June 2019.

21. Securing Downlink Non-Orthogonal Multiple Access Systems by Trusted Relays
    A. Arafa, W. Shin, M. Vaezi, and H. V. Poor
    IEEE Global Communications Conference (Globecom), Abu Dhabi, UAE, December 2018.

22. Relay-Aided Secure Broadcasting for VLC
    A. Arafa, E. Panayirci, and H. V. Poor
    IEEE Global Conference on Signal and Information Processing (GlobalSIP), Anaheim, California, November 2018.

23. Downlink Non-Orthogonal Multiple Access Systems with an Untrusted Relay
    A. Arafa, W. Shin, M. Vaezi, and H. V. Poor
    Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, California, October 2018.

24. Online Timely Status Updates with Erasures for Energy Harvesting Sensors
    A. Arafa, J. Yang, S. Ulukus, and H. V. Poor
    Allerton Conference on Communication, Control, and Computing, Monticello, Illinois, October 2018.

25. Age-Minimal Online Policies for Energy Harvesting Sensors with Radom Battery Recharges
    A. Arafa, J. Yang, and S. Ulukus
    IEEE International Conference on Communications (ICC), Kansas City, Missouri, May 2018.

26. Age-Minimal Online Policies for Energy Harvesting Sensors with Incremental Battery Recharges
    A. Arafa, J. Yang, S. Ulukus, and H. V. Poor
    Information Theory and Applications (ITA) Workshop, San Diego, California, February 2018.

27. Age-Minimal Transmission in Energy Harvesting Two-Hop Networks
    A. Arafa and S. Ulukus
    IEEE Global Communications Conference (Globecom), Singapore, December 2017.

28. Age Minimization in Energy Harvesting Communications: Energy-Controlled Delays
    A. Arafa and S. Ulukus
    Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, California, October 2017.

29. Near Optimal Online Distortion Minimization for Energy Harvesting Nodes
    A. Arafa and S. Ulukus
    IEEE International Symposium on Information Theory (ISIT), Aachen, Germany, June 2017.

30. Energy Harvesting Networks with General Utility Functions: Near Optimal Online Policies
    A. Arafa, A. Baknina, and S. Ulukus
    IEEE International Symposium on Information Theory (ISIT), Aachen, Germany, June 2017.

31. Mobile Energy Harvesting Nodes
    A. Arafa and S. Ulukus
    IEEE International Conference on Communications (ICC), Paris, France, May 2017.

32. Energy Harvesting Cooperative Multiple Access Channel with Decoding Costs
    A. Arafa, O. Kaya, and S. Ulukus
    European Signal Processing Conference (EUSIPCO), Budapest, Hungary, August 2016.

33. Energy Harvesting Two-Way Channel with Decoding Costs
    A. Arafa, A. Baknina, and S. Ulukus
    IEEE International Conference on Communications (ICC), Kuala Lumpur, Malaysia, May 2016.

34. Delay Minimal Policies in Energy Harvesting Broadcast Channels
    M. Fu, A. Arafa, S. Ulukus, and W. Chen
    IEEE International Conference on Communications (ICC), Kuala Lumpur, Malaysia, May 2016.

35. Optimal Policies in Energy Harvesting Two-Way Channels with Processing Costs
    A. Arafa, A. Baknina, and S. Ulukus
    International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt), Tempe, Arizona, May 2016.

36. Single-User and Multiple Access Channels with Energy Harvesting Transmitters and Receivers
    A. Arafa and S. Ulukus
    IEEE Global Conference on Signal and Information Processing (GlobalSIP), Atlanta, Georgia, December 2014.

37. A Feedback- Soft Sensing-Based Cognitive Access Scheme with Feedback Erasures
    A. Arafa, K. Seddik, A. Sultan, T. ElBatt, and A. El-Sherif
    IEEE Wireless Communications and Networking Conference (WCNC), Istanbul, Turkey, April 2014.

38. A Soft Sensing-Based Cognitive Access Scheme Exploiting Primary Feedback
    A. Arafa, K. Seddik, A. Sultan, T. ElBatt, and A. El-Sherif
    International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt), Paderborn, Germany, May 2012.

39. A Feedback-Based Access Scheme for Cognitive Radio Systems
    K. Seddik, A. Sultan, T. ElBatt, A. El-Sherif, and A. Arafa
    IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), San Francisco, California, June 2011.

PhD Thesis

Energy Harvesting Communication Networks with System Costs (UMD ECE Distinguished Dissertation Award)
A. Arafa
University of Maryland College Park, 2017.