Computer Science – Information Theory
Scientific paper
2010-03-03
Computer Science
Information Theory
The conference version of this work has been submitted to ISIT 2010
Scientific paper
A $K$-user secure Gaussian Multiple-Access-Channel (MAC) with an external eavesdropper is considered in this paper. An achievable rate region is established for the secure discrete memoryless MAC. The secrecy sum capacity of the degraded Gaussian MIMO MAC is proven using Gaussian codebooks. For the non-degraded Gaussian MIMO MAC, an algorithm inspired by interference alignment technique is proposed to achieve the largest possible total Secure-Degrees-of-Freedom (S-DoF). When all the terminals are equipped with a single antenna, Gaussian codebooks have shown to be inefficient in providing a positive S-DoF. Instead, a novel secure coding scheme is proposed to achieve a positive S-DoF in the single antenna MAC. This scheme converts the single-antenna system into a multiple-dimension system with fractional dimensions. The achievability scheme is based on the alignment of signals into a small sub-space at the eavesdropper, and the simultaneous separation of the signals at the intended receiver. Tools from the field of Diophantine Approximation in number theory are used to analyze the probability of error in the coding scheme. It is proven that the total S-DoF of $\frac{K-1}{K}$ can be achieved for almost all channel gains. For the other channel gains, a multi-layer coding scheme is proposed to achieve a positive S-DoF. As a function of channel gains, therefore, the achievable S-DoF is discontinued.
Bagherikaram Ghadamali
Khandani Amir K.
Motahari Abolfazl S.
No associations
LandOfFree
On the Secure Degrees-of-Freedom of the Multiple-Access-Channel does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with On the Secure Degrees-of-Freedom of the Multiple-Access-Channel, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Secure Degrees-of-Freedom of the Multiple-Access-Channel will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-683930