On the Limitation of Embedding Cryptographic Signature for Primary Transmitter Authentication

Recently, an interesting primary transmitter authentication scheme was proposed. The main idea of this scheme is to have the primary transmitter embed cryptographic authentication tag at the physical layer. There are a number of features that make this scheme attractive. In this paper, we investigate the effective coverage areas for the primary and secondary receivers before and after applying this scheme. During the process, we reveal a serious limitation of this scheme, which may prohibit its application in practice.