Automatic Secret Keys From Reciprocal MIMO Wireless Channels: Measurement and Analysis

Jon W. Wal, Rajesh K. Sharma
2010 IEEE Transactions on Information Forensics and Security  
Information theoretic limits for random key generation in multiple-input multiple-output (MIMO) wireless systems exhibiting a reciprocal channel response are investigated experimentally with a new three-node MIMO measurement campaign. As background, simple expressions are presented for the number of available key bits, as well as the number of bits that are secure from a close eavesdropper. Two methods for generating secret keys are analyzed in the context of MIMO channels and their mismatch
more » ... e and efficiency are derived. A new wideband indoor MIMO measurement campaign in the 2.51-to 2.59-GHz band is presented, whose purpose is to study the number of available key bits in both line-of-sight and nonline-of-sight environments. Application of the key generation methods to measured propagation channels indicates key generation rates that can be obtained in practice for four-element arrays. Index Terms-Cryptography , encryption, measurement, MIMO, time varying channels. 1556-6013/$26.00 © 2010 IEEE Authorized licensed use limited to: Jacobs University Bremen. Downloaded on August 13,2010 at 07:13:46 UTC from IEEE Xplore. Restrictions apply. Jon W. Wallace (S'99-M'03) received the B.S. (summa cum laude) and Ph.D. degrees in electrical engineering from Brigham Young University (, Nepal. His current research interests include cognitive radio, MIMO communications, wireless physical layer security, and wireless channel modeling. During his B.Sc. and M.Eng. studies, Mr. Sharma was supported by scholarships from the government of Pakistan and the government of Finland, respectively. Authorized licensed use limited to: Jacobs University Bremen. Downloaded on August 13,2010 at 07:13:46 UTC from IEEE Xplore. Restrictions apply.
doi:10.1109/tifs.2010.2052253 fatcat:wtghogwdvngz3gpscae4qcaaeq