This book introduces the fundamentals of physical layer security (PLS) and demonstrates how a variety of PLS techniques can be applied to improve the security of wireless communication systems. In particular, this book covers three security aspects of wireless communications. It includes secrecy, i.e., preventing eavesdroppers from intercepting information from transmitted wireless signals, covertness, i.e., hiding the transmitted signals themselves from malicious wardens and authentication, i.e., authenticating the identities of communicating entities. 

When discussing the secrecy...