Chaotic Standard Map Based Frequency Hopping OFDMA for Low Probability of Intercept

In frequency hopping (FH)-OFDMA, the transmitted symbols on all subcarriers are demodulated by FFT at once at the receiver. Thus, these symbols can be easily intercepted by an adversary radiometer when the number of simultaneous transmitting users is small. In this letter, we design a chaotic standard map (CSM) based FH pattern for low probability of intercept. Through the proposed scheme, more than two symbols of the same user can be shown in the same symbol period, or none. Moreover, the order of these symbols is mixed. It makes the radiometer difficult in intercepting these symbols, and thus, it achieves a low probability of intercept. We show that the proposed scheme satisfies requirements of a desired FH pattern.