Correlated Noise Reduction for Electromagnetic Analysis

Hongying LIU  Xin JIN  Yukiyasu TSUNOO  Satoshi GOTO  

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E96-A   No.1   pp.185-195
Publication Date: 2013/01/01
Online ISSN: 1745-1337
DOI: 10.1587/transfun.E96.A.185
Print ISSN: 0916-8508
Type of Manuscript: Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Implementation
electromagnetic analysis (EMA),  power analysis,  electromagnetic leakage,  correlated noise,  singular value decomposition,  

Full Text: PDF>>
Buy this Article

Electromagnetic emissions leak confidential data of cryptographic devices. Electromagnetic Analysis (EMA) exploits such emission for cryptanalysis. The performance of EMA dramatically decreases when correlated noise, which is caused by the interference of clock network and exhibits strong correlation with encryption signal, is present in the acquired EM signal. In this paper, three techniques are proposed to reduce the correlated noise. Based on the observation that the clock signal has a high variance at the signal edges, the first technique: single-sample Singular Value Decomposition (SVD), extracts the clock signal with only one EM sample. The second technique: multi-sample SVD is capable of suppressing the clock signal with short sampling length. The third one: averaged subtraction is suitable for estimation of correlated noise when background samplings are included. Experiments on the EM signal during AES encryption on the FPGA and ASIC implementation demonstrate that the proposed techniques increase SNR as much as 22.94 dB, and the success rates of EMA show that the data-independent information is retained and the performance of EMA is improved.