Secrecy-Enhancing Channel Estimation in Multi-Antenna Wireless Systems

This chapter provides an overview of the so-called discriminatory channel estimation (DCE) scheme, that is, a training and channel estimation scheme utilized to enhance physical layer secrecy in the channel estimation phase. Instead of focusing on the data transmission, as done in most works introduced in previous chapters, the DCE scheme focuses on the training signal design in the channel estimation phase and aims to discriminate the channel estimation performance at the destination and the eavesdropper. By allowing the destination to obtain a better channel estimate than the eavesdropper, the difference in signal qualities at the two receivers will increase, leaving more room for secrecy coding in the data transmission phase.