Impact of Denial-of-Service Attack on Directional Compact Geographic Forwarding Routing Protocol in Wireless Sensor Networks

Directional Compact Geographic Forwarding (DCGF) routing protocol promises a minimal overhead generation by utilizing a smart antenna and Quality of Service (QoS) aware aggregation. However, DCGF was tested only in the attack-free scenario without involving the security elements. Therefore, an investigation was conducted to examine the routing protocol algorithm whether it is secure against attack-based networks in the presence of Denial-of-Service (DoS) attack. This analysis on DoS attack was carried out using a single optimal attacker, A1, to investigate the impact of DoS attack on DCGF in a communication link. The study showed that DCGF does not perform efficiently in terms of packet delivery ratio and energy consumption even on a single attacker.

Sidelobe level minimization for uniform circular smart antenna array using cultural algorithm

Cultural algorithm (CA) is a new evolutionary program inspired by sociology and archaeology theories that assisting formulating cultural evaluation. Its use to solve optimization problems. This paper analyzed the beamforming of a uniform circular antenna array (UCAA) via using the CA algorithm. The sidelobe level (SLL) is minimized by adjusting the appropriate weight for each element. In addition, the optimal beam pattern is achieved by using CA for UCAA, which means that the main beam is steering to the desired user, while the nulls represent the interference signals. The excitation amplitude is supposed to be constant while the elements are assumed isotropic. The circular array number elements and the interspacing distance between them are setting as optimization parameters. The simulation results show that the CA rationally reacts to the changing environments, and it is valuable for SLL reduction. A −25 dB of relative SLL is achieved under beam scanning (0º) and (15º), respectively.

Improved Linearly Constrained Minimum Variance Algorithm for 5G Communications System

Beamforming is a process formulated to produce the radiated beam patterns of the antennas by completely building up the processed signals in the direction of the desired terminals and cancelling beams of interfering signals. Adaptive beamforming is a key technology of smart antenna. The core is to obtain optimum weights of the antenna array by some adaptive beamforming algorithms and finally adjust the main lobe to focus on the arriving direction of the desired signal as well as suppressing the interfering signal. There are several beamforming algorithms that includes Linearly Constrained Minimum Variance (LCMV) algorithm in which Self Nulling Issue is further reduced by adding multiplier to the MCMV algorithm and it is referred as Improved LCMV (IMPLCMV). A Comparative analysis is done for different multipliers and it is found that w=0.15 gives best result with minimum interference of flat response and also self-nulling issues can be reduced.

A Novel Metaheuristic Moss-Rose-Inspired Algorithm with Engineering Applications

Every day, a moss rose generates new flowers with variable diameters. Two flowering mechanisms are controlled by exposure to sunlight, namely, a variable concentration of florigen based on photoreceptors called phytochromes, and the biological clock, which is responsible for the changing diameters of the plant flowers at night and some hours during the day. By explaining and idealizing the flowering mechanisms of the moss rose in nature, a new sort of nature-inspired optimization algorithm called the moss rose optimization algorithm (MROA) was proposed in this study. The MROA was benchmarked using three methods. First, 18 benchmark functions were utilized to evaluate the effectiveness of the MROA. Second, the MROA was used for planning a smart antenna system (SA) as an online solution to find unknown weights. Third, the MROA was used to find the optimal dimensions for a microstrip antenna for the frequency (2.4 GHz) as an offline solution. The MROA was compared with other algorithms. The results show the capacities and proficiencies of the proposed algorithm regarding finding the ideal solutions. The promising arrangements for smart antenna identification and microstrip antenna design highlight the importance of this algorithm for resolving current issues with unknown fields of investigation.