Design of an initial condition‐index chaos shift keying modulation

Abstract

An initial condition-index chaos shift keying modulation is proposed. This design aims to increase the spectral and energy efficiencies to unprecedented levels. The proposed scheme exploits the initial conditions to generate different chaotic sequences to convey extra bits per transmission. In the proposed design, the input data stream is formed in blocks of p tot = n + 1 bits. In this architecture, n bits are mapped into N = 2 n predetermined initial conditions that are used to generate unique chaotic sequences at the transmitter. At the receiver side, the predetermined initial conditions are used to generate a set of N chaotic sequences that are correlated with the received signal. The index of the initial condition for which the chaotic sequence produces a maximum correlation with the received signal is selected to recover the mapped bits, and the corresponding sequence is used to despread the transmitted modulated bit. To validate the proposed scheme, the bit error rate over fading channels is analysed and formulated and the proposed system performance is compared with other conventional and index modulation schemes. In comparison to rival modulation schemes, the results obtained in the proposed work show a competitive performance.

Adaptive OFDM‐IM for Enhancing Physical Layer Security and Spectral Efficiency of Future Wireless Networks

“…The proposed techniques are simple and can reduce PAPR without sacrificing data rate. In [12], authors proposed a scheme to enhance the spectral and energy efficiency by using initial conditions to generate different chaotic sequences that can convey extra bits per transmission.…”

“…where 0, is the noise variance in frequency domain ( 0, = ( / ) 0, ). In (12), numerical overflow can be prevented by using the Jacobian logarithm [27]. For example, for = 2 and = /2, (12) simplifies to…”

“…. In order to detect the active indices, LLR value corresponding to each subcarrier is calculated using (12). Afterwards, the receiver calculates the sum of LLRs corresponding to each combination of the subcarriers in the lookup table with respect to subblock based SAR as follows:…”

Pseudorandom Number Generator (PRNG) Design Using Hyper-Chaotic Modified Robust Logistic Map (HC-MRLM)

“…Random number sequences have immense impact on numerous applications, such as signal processing [1,2], stochastic simulations [3,4], spread spectrums [5,6], gaming [7][8][9], statistics [10], captcha [11,12], machine learning [13,14], and cryptography etc. The random number generators that pertain to excellent statistical properties are considered critical for robust cryptographic applications [15].…”

A Multiple‐Access Time and Frequency Spectrum‐Spreading Modulation

“…Continuous phase modulation combined with DSSS is proposed in [14] and further investigated in [15][16][17][18]. Recently, index modulation has been applied to a coherent chaos-based scheme where the initial conditions of the chaotic sequence are used as a new dimension to map information and carry extra bits [19]. All the proposed modulation methods above come with a number of unique features.…”