Finite length of sequences that are modulated both in phase and amplitude and have an ideal autocorrelation function (ACF) consisting of merely a pulse have many applications in control and communication systems. They are widely applied in control and communication systems, such as in pulse compression systems for radar and deep-space ranging problems [1-5]. In radar design, the important part is to choose a waveform, which is suitable to be transmitted because the waveform controls resolution in clutter performance. In addition, it can solve a general signal problem particularly related to the digital processing. Energy ratio (ER), total side lobe energy (SLE), and peak sidelobe level (PSL) are three properties of such sequences interest. This paper presents a method using the Complementation, Cyclic Shift and Bit Addition for synthesizing and optimizing a binary sequence implemented to improve the sequences of a similar quality with the Barker sequence, particularly for lengths greater than 13. All of these methods are guided by the specific parameter with good characteristics in ACF (ER, SLE, and PSL) [6,7,8]. Such sequences can then be effectively used to improve the range and Doppler resolution of radars.

The metaheuristic algorithm is a popular research area for solving various optimization problems. In this study, we proposed two approaches based on the Sine Cosine Algorithm (SCA), namely, modification and hybridization. First, we attempted to solve the constraints of the original SCA by developing a modified SCA (MSCA) version with an improved identification capability of a random population using the Latin Hypercube Sampling (LHS) technique. MSCA serves to guide SCA in obtaining a better local optimum in the exploitation phase with fast convergence based on an optimum value of the solution. Second, hybridization of the MSCA (HMSCA) and the Cuckoo Search Algorithm (CSA) led to the development of the Hybrid Modified Sine Cosine Algorithm Cuckoo Search Algorithm (HMSCACSA) optimizer, which could search better optimal host nest locations in the global domain. Moreover, the HMSCACSA optimizer was validated over six classical test functions, the IEEE CEC 2017, and the IEEE CEC 2014 benchmark functions. The effectiveness of HMSCACSA was also compared with other hybrid metaheuristics such as the Particle Swarm Optimization–Grey Wolf Optimization (PSOGWO), Particle Swarm Optimization–Artificial Bee Colony (PSOABC), and Particle Swarm Optimization–Gravitational Search Algorithm (PSOGSA). In summary, the proposed HMSCACSA converged 63.89% faster and achieved a shorter Central Processing Unit (CPU) duration by a maximum of up to 43.6% compared to the other hybrid counterparts.

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This paper presents a design of a wearable textile microstrip patch rectifying antenna (rectenna) array operating for wireless body area network (WBAN) at the center frequency, <em>f_c</em> of 2.45 GHz.  Precisely, jeans or denim with the relative permittivity, = 1.70 and thickness of 1.00 mm is chosen as a substrate attached to SheildIt Super as a conductive material with the thickness, <em>h</em> of 0.17 mm and conductivity of 6.67  10⁵ S/m, respectively. In the first stage, a microstrip patch antenna array layout with the inset fed technique is designed and simulated by using the Keysight Advanced Design System (ADS) software.  In the second stage, a wearable textile microstrip patch antenna array is fabricated, integrated, and hidden inside the jeans fabric.  In the third stage, the rectifier circuit layout on the flame retardant-4    (FR-4) printed circuit board (PCB) with the dielectric constant,  = 4.7, thickness, <em>h</em> = 1.6 mm, and loss tangent, <em>δ</em> = 0.018 that can generate radio frequency-direct current (RF-DC) conversion is designed and simulated using the ADS software  Each simulation result and fabrication measurement shows that the designed antenna array characteristics are suitable for an industrial, scientific, and medical radio (ISM) band by having the reflection coefficient, <em>S</em>₁₁ less than -10 decibel (dB) at the respective resonant frequency, <em>f_r.</em>  Moreover, through simulation, the output DC voltage for the bridge rectifier circuit is from 132 mV to 5.01 V with the corresponding power conversion efficiency (PCE) between 3.48% and 50.20% whereas for the voltage doubler rectifier, the output DC voltage is from 417 mV to 2.91 V with the corresponding PCE between 34.78% and 53.56%, respectively.

In this study, we proposed a bio-inspired technique known as modified cuckoo search (MCS)-based weighted sum algorithm towards synthesizing symmetric linear array geometry with minimum side lobe level (SLL) and/or nulls control. The newly evolved metaheuristic algorithm was primarily based on the natural obligate brood parasitic behavior of some cuckoo species in combination with the Lévy flight behavior of some birds and fruit flies. Through the integration with the Roulette wheel selection operator and the inertia weight controlling the position (solution) exploration, the MCS-based weighted sum approach optimized concurrently the array element excitation locations, amplitudes, and phases within the uniform pattern and Dolph-Chebyshev window, respectively. The optimal solutions obtained were then compared against the conventional (with λ/2 inter-element distance) and other chosen evolutionary algorithms-based arrays.

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