There is no doubt that chaotic systems are still attractive issues in various radar applications and communication systems. In this paper, we present a new 0.3 GHz mono-static microwave chaotic radar. It includes a chaotic system based on a time-delay to generate and process frequency modulated (FM) waveforms. Such a radar is designed to extract high-resolution information from the targets. To generate a continuous FM signal, the chaotic signal is first modulated using the voltage control oscillator (VCO). Next, the correct value for the loop gain (G) is carefully set when utilizing the Phase-Locked Loop (PLL) at the receiver, so that the instantaneous frequency that reflects a chaotic state variable can be reliably recovered. In this system, the PLL synchronization and radar correlation are enough to recover the echo signal and detect the target. The finding indicates that the system can be implemented with no need to use the complete self-synchronization or complex projective synchronization schemes as compared to the existing chaotic radar systems. The simulation results show that the short-time cross-correlation of the transmitted and reconstructed waveforms is good and satisfactory to detect the target under various signal-to-noise ratio (SNR) levels and with less complexity in the design.

Over the last few decades, complex multi-scroll chaotic attractors generated through electronic circuits have considerably been raised. Therefore, this paper concerns the design and implementation of multi-scroll chaotic attractors such as two-scrolls, three-scrolls and four-scrolls generated from a first-order delay differential equation. Modelling a time-delayed feed-back chaotic system considers a simple nonlinearity piecewise-linear (PWL) function to generate the chaotic attractors with an odd/even numbers of scrolls. The delayed feedback consists of a cascade of Bessel filters and the design of a circuit which generates a string of scrolls chaotic attractors depending on the number of intersection points of nonlinearity of PWL function with a state variable. The simulation results reveal that the multiple-scroll chaotic attractors can be successfully reproduced using PSpice. The implementation based on circuitswitching mode with simple components such as resistors, capacitors, and operational amplifiers is also presented.

This paper presents and analyzes a new four-dimensional (4D) jounce hysteresis chaotic dynamical system and investigates its application to robust communication. An adaptive chaotic synchronization scheme is developed based on the proposed 4D jounce system, in which an adaptive controller is designed at the receiver to achieve robust synchronization between the master and slave systems in the presence of uncertain system parameters. Lyapunov stability theory is employed to derive the adaptive control laws and parameter-update rules required for online estimation of the uncertain receiver-side parameters. For chaos-based communication, multiple information signals are encoded by modulating selected parameters of the chaotic transmitter system. At the receiver, the adaptive parameter estimator tracks the transmitted time-varying parameter, enabling reliable information recovery through a midpoint-thresholding decision scheme after the initial transient period. The performance and robustness of the proposed communication framework are evaluated through comprehensive numerical simulations under additive white Gaussian noise (AWGN) at different noise levels. The results demonstrate accurate chaotic synchronization, reliable information recovery, and robustness against channel noise, indicating the potential of the proposed 4D jounce chaotic system for robust and noise-tolerant communication applications.