Secure Degrees of Freedom Region of the Two-User MISO Broadcast Channel with Alternating CSIT

Pritam Mukherjee, Ravi Tandon, Sennur Ulukus

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23 Scopus citations


The two user multiple-input single-output (MISO) broadcast channel with confidential messages (BCCM) is studied, in which the nature of channel state information at the transmitter (CSIT) from each user can be of the form Ii, i = 1, 2 where I1, I2 ϵ {P,D,N}, and the forms P, D, and N correspond to perfect and instantaneous, completely delayed, and no CSIT, respectively. Thus, the overall CSIT can alternate between nine possible states corresponding to all possible values of I1 I2, with each state occurring for λI1 I2 fraction of the total duration. We assume that perfect and instantaneous CSI is available at the all receivers. The main contribution of this paper is to establish the secure degrees of freedom (s.d.o.f.) region of the MISO BCCM with alternating CSIT with the symmetry assumption, where λI1 I2 = λI2 I1 . The main technical contributions include developing 1) novel achievable schemes for MISO BCCM with alternating CSIT with security constraints, which also highlight the synergistic benefits of inter-state coding for secrecy; 2) new converse proofs via local statistical equivalence and channel enhancement; and 3) showing the interplay between various aspects of channel knowledge and their impact on s.d.o.f.

Original languageEnglish (US)
Article number7840026
Pages (from-to)3823-3853
Number of pages31
JournalIEEE Transactions on Information Theory
Issue number6
StatePublished - Jun 2017


  • Information theoretic security
  • alternating channel state information (CSI)
  • broadcast channel
  • multiple-input single-output (MISO)
  • secure degrees of freedom

ASJC Scopus subject areas

  • Information Systems
  • Computer Science Applications
  • Library and Information Sciences

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