Phase-Separated DCSK: A Simple Delay-Component-Free Solution for Chaotic Communications

Chaos-Based Underwater Communication With Arbitrary Transducers and Bandwidth

“…In this section, the conventional DCSK using logistic map [21], NR-DCSK [23], RM-DCSK [27], HE-DCSK [28], PS-DCSK [30], CDSK [31], and the proposed method with the same transmission rate are compared in the AWGN channel with different bit energy to noise power spectral density (E b /N 0 ) ratios. Figure 5 shows BER for the different methods versus E b /N 0 with the data transmission rate R b = 1000 bits/s, where the spreading gain L = 150, n samp = 10, N s = 15, and the frequency of the sinusoidal signal is f = 50 kHz.…”

“…The DCSK and its modified versions exhibit both low bit error rate (BER) and robustness against channel distortion [23][24][25][26]. Most of the previous researcher focused on the problem of low data transmission rate [25][26][27][28][29][30][31], in which half of bit energy is used to transmit the reference signal. In Reference [27], Yang and Jiang proposed a Reference-Modulated DCSK (RM-DCSK) system; the first information bit is sent in the first time slot, and the waveform in the second slot carries not only the second information bit but also the reference signal of the next frame.…”

“…High data rate Code Shift DCSK (HCS-DCSK) system [29] uses the sum of multiple bits multiplied by different (uncorrelated) chaotic references to form the transmitting signal for just one frame to achieve high bit rate, but it needs the synchronized chaotic references at the receiver, which is difficult to implement. Phase-Separate DCSK (PS-DCSK) system [30] uses the sinusoidal and its orthogonal signals to separate the reference signals and the information bearing signals, respectively. It not only avoids radio frequency delay lines, which is difficult to integrate in Complementary Metal Oxide Semiconductor (CMOS) technology, but it also achieves twice as much data rate as the original DCSK.…”

“…Encouraged by those works, a DCSK system is proposed based on a first order hybrid chaotic system and the PS-DCSK system. In this method, the chaotic signals are generated by the first order hybrid system rather than the logistic maps used in Reference [30]. There is a basis function for the first order hybrid chaotic system.…”

“…In Section 3, simulation results of the proposed method are given and compared with the conventional DCSK [21], NR-DCSK [23], RM-DCSK [27], HE-DCSK [28], Phase-Separate DCSK [30] (PS-DCSK) and correlation delay shift keying [31] (CDSK). Conclusions are given in Section 4.…”