The invention discloses a shifted sub-carrier-based frequency domain chaotic cognitive radio system comprising a transmitter and a receiver. At the transmitter, a frequency domain chaotic signal generator is configured to generate a frequency domain-based chaotic signal c(t), a sub-carrier correspondence module is configured to dynamically change a corresponding relationship between a chaotic sequence C(k) and a sub-carrier, data information undergoes a binary phase shift keying modulation to provide b(t), b(t) and c(t) are modulated together to provide s(t), and s(t) is further modulated with a carrier and transmitted over a radio channel in an available frequency band. At the receiver, after coherent carrier demodulation, a frequency domain chaotic signal generator is configured to generate a frequency domain-based chaotic signal c(t), the chaotic signal c(t) is then synchronized and used to demodulate a receiving signal r(t) to obtain d(t), a zero-crossing determination is performed on d(t) to obtain an estimate b̑(t) of an information bit, thereby successfully receiving the transmitted information. The shifted sub-carrier-based frequency domain chaotic cognitive radio system disclosed by the invention significantly improves security of a conventional frequency domain chaotic cognitive radio system.
SHIFTED SUB-CARRIER-BASED FREQUENCY DOMAIN CHAOTIC COGNITIVE RADIO SYSTEM