Date & Time: 

   2024 /11 / 22  (Fri) 14:20 - 16:20

 

Location: 

   Delta Building R216, NTHU

 

Speaker: 

    王奕翔 教授

   國立台灣大學電機工程學系

 

Topic: 

  On the Role of State Feedback in Packet Erasure Networks

 

Abstract: 

   Packet communication is prevalent in modern wireless networks, for which the packet erasure channel is a canonical channel model. While many network protocols rely on simple state feedback (ACK/NACK) of a transmitted packet for traffic management and access control, from an information theoretic point of view, such feedback cannot enhance the point-to-point channel capacity. Meanwhile, in multi-user systems such as the broadcast packet erasure channel, it has been shown that the constant-bit state feedback provides capacity gain linear in the size of a packet. In this talk, I will discuss the role of state feedback in packet erasure networks. Emphasis will be laid on how state feedback from a single user helps increase capacity and security of the entire system. For normal communication over the two-user broadcast packet erasure channel, it turns out that single-user state feedback suffices to achieve the full-feedback capacity region, and it helps facilitate opportunistic network coding for side information exploitation. For secret communication, it is shown that surprisingly with single-user feedback, even if the non-feedback user has a weaker transmitter-receiver link, a strictly positive secret communication rate is achievable. The single-user state feedback helps generate a secret key for the feedback user and create a randomizer for wiretap-channel coset coding of the non-feedback user.

 

Autobiography: 

  I-Hsiang Wang received the B.Sc. degree in electrical engineering from National Taiwan University, Taiwan, in 2006. He received a Ph.D. degree in electrical engineering and computer sciences from the University of California at Berkeley, USA, in 2011. From 2011 to 2013, he was a postdoctoral researcher at École Polytechnique Fédérale de Lausanne, Switzerland. Since 2013, he has been at the Department of Electrical Engineering in National Taiwan University, where he is now a full professor. His research interests include network information theory, networked data analysis, and statistical learning. He was a finalist of the Best Student Paper Award of IEEE International Symposium on Information Theory, 2011. He received the 2017 IEEE Information Theory Society Taipei Chapter and IEEE Communications Society Taipei/Tainan Chapters Best Paper Award for Young Scholars. He held the Irving T. Ho Outstanding Young Chair Professorship in the College of Electrical Engineering and Computer Sciences, National Taiwan University, from 2021 to 2022. He won the National Taiwan University Distinguished Teaching Award (top 1% of the university teaching staff, awarded for 5 years) in 2017, the NTU EECS Academic Contribution Award in 2021, and the NSTC Project for Excellent Junior Research Investigators from 2021 to 2024 and from 2024 to 2028. He also serves as an Associate Editor for the IEEE Transactions on Information Theory.