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This paper presents the development of an autopilot system for self-driving an autonomous wheeled vehicle. A mathematical model, including the power allocation system, has been designed for a vehicle with three degrees of freedom. All model parameters have been identified through experimental trials. Heading and speed controllers were designed based on Lyapunov theory. These controllers have been further fine-tuned and tested through simulations to verify their robustness against external disturbances in the system dynamics. Moreover, this work proposes guidance approaches that allow the vehicle to track desired waypoints (line of sight (LOS)), and follow a given path (cross-track error) and a predefined trajectory with obstacle avoidance. A comparative study was also proposed in this paper, wherein we evaluate the paths followed by the vehicle using distinct yaw moment control techniques which are; differential thrust controller, solely relying on a steering controller, and a combination of both. To validate the effectiveness of the proposed autopilot system, we have conducted experimental tests, specifically focusing on waypoint tracking control (LOS method). The results underscore the system’s capabilities and its potential in real-world applications.

Fair power allocation to the users in a power domain nonorthogonal multiple access (PD-NOMA) networks is an essential aspect. In this paper, we have proposed a coefficient-scaling-based fair power allocation scheme, for a single cell multi-user PD-NOMA network. First, we have developed a model for two users with a fixed power allocation scheme, and proposed a modified strong user fair-power allocation scheme. Furthermore, this two-user scheme is extended for an ad-hoc multi-user PD-NOMA network and a coefficient-scaling-based approach for fair power allocation is proposed to address the outage issue. The performance of the proposed schemes is evaluated through bit-error-rate, sum-rate, outage, and fairness index. The simulation results reveal a remarkable increase in fairness performance of the proposed scheme, in comparison with a state-of-the-art method.

In this paper, a simplified Generalized Code-Shifted Differential Chaos Shift Keying (GCS-DCSK) whose transmitter never needs any delay circuits, is proposed. However, its performance is deteriorated because the orthogonality between substreams cannot be guaranteed. In order to optimize its performance, the system model of the proposed GCS-DCSK with power allocations on substreams is presented. An approximate bit error rate (BER) expression of the proposed model, which is a function of substreams’ power, is derived using Gaussian Approximation. Based on the BER expression, an optimal power allocation strategy between information substreams and reference substream is obtained. Simulation results show that the BER performance of the proposed GCS-DCSK with the optimal power allocation can be significantly improved when the number of substreams $M$ is large.