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Authentication scheme to combat a primary user emulation attack against cognitive radio users

Cognitive radios are a good fit for overcoming inefficient usage of the available radio spectrum, allowing secondary users to utilize the spectrum when the primary licensed users are not consuming it. This requires secondary users to continuously observe their spectrum utilization to prevent interfering with the primary user's transmissions. However, an adversary can exploit this to gain unfair use of the spectrum. Such an attack is known a primary user emulation attack. To avoid these attacks, a method of authenticating the primary user's signal is required. This work addresses embedding such an authentication message with the binary phase shift keying and eight-phase shift keying modulation techniques, parity bits of the error control codes, and pre-coder bit of the modified duo-binary scheme, and analyses of the error performance have been carried out with the aid of their performance graphs. Copyright © 2015 John Wiley & Sons, Ltd.