2017/12/12 by Rick Fritschek, Fritschek, Rick, Gerhard Wunder +1
Engineering · Computer Science · #Wireless Communication Security Techniques #Cryptographic Implementations and Security #Cryptography and Data Security
paper · pdf · doi:10.48550/arxiv.1712.04274
We study deterministic approximations of the Gaussian two-user multiple\naccess wiretap channel (G-MAC-WT) and the Gaussian wiretap channel with a\nhelper (G-WT-H). These approximations enable results beyond the recently shown\n2/3 and 1/2 secure degrees of freedom (s.d.o.f.) for the G-MAC-WT and the\nG-WT-H, respectively. While the s.d.o.f. were obtained by real interference\nalignment, our approach uses signal-scale alignment. We show achievable schemes\nwhich are independent of the rationality of the channel gains. Moreover, our\nresults can differentiate between channel strengths, in particular between both\nusers, and establishes secrecy rates dependent on this difference. We can show\nthat the resulting achievable secrecy rates tend to the s.d.o.f. for vanishing\nchannel gain differences. Moreover, we extend previous and develop new\ntechniques to prove general s.d.o.f. bounds for varying channel strengths and\nshow that our achievable schemes reach the bounds for certain channel gain\nparameters. We believe that our analysis is the next step towards a\nconstant-gap analysis of the G-MAC-WT and the G-WT-H.\n