Livestock management is an emerging area of application of the quadrotor, especially for monitoring, counting, detecting, recognizing, and tracking animals through image or video footage. The autonomous operation of the quadrotor requires the development of an obstacle avoidance scheme to avoid collisions. This research develops an obstacle avoidance-based autonomous navigation of a quadrotor suitable for outdoor applications in livestock management. A Simulink model of the UAV is developed to achieve this, and its transient and steady-state performances are measured. Two genetic algorithm-based PID controllers for the quadrotor altitude and attitude control were designed, and an obstacle avoidance algorithm was applied to ensure the autonomous navigation of the quadrotor. The simulation results show that the quadrotor flies to the desired altitude with a settling time of 6.51 s, an overshoot of 2.65%, and a steady-state error of 0.0011 m. At the same time, the attitude controller records a settling time of 0.43 s, an overshoot of 2.50%, and a zero steady-state error. The implementation of the obstacle avoidance scheme shows that the distance threshold of 1 m is sufficient for the autonomous navigation of the quadrotor. Hence, the developed method is suitable for managing livestock with the average size of an adult sheep.

Microstrip patch antennas have been widely used in contemporary mobile communication technology, including 5G. Previous studies in the area have shown that such antennas can be optimized to operate in different bands of 5G. This study proposes a microstrip patch antenna designed to operate at 26 and 28 GHz and aimed at improving the gain and other radiation characteristics by adding a combination of different slot shapes to a single rectangular patch that is very common and popular in 5G antennas. The results show that the gain is noticeably increased by inserting two hammer slots and a rectangular slot in the middle between them. The dimensions of the slots are optimized using the CST Studio Suite simulator. A comparative analysis was performed to demonstrate the superiority of the proposed over previous designs in terms of gain value and other radiation parameters. The results suggest that such a very simple and low-profile antenna can be a good candidate for 5G mobile applications.

The microstrip patch antenna is used in various communication applications including cellular phones, satellites, missiles, and radars, due to its several attractive features such as small size and weight, low cost, and easy fabrication. The microstrip patch antenna consists of a top radiating patch, a bottom ground plane, and a dielectric substrate in between. The patch can have different shapes, the rectangular patch being the most commonly used. In practice, the microstrip antenna suffers from narrow bandwidth and low gain efficiency. This paper aims to enhance the bandwidth and efficiency of a rectangular-patch antenna using the High-Frequency Structure Simulator (HFSS). Initially different patch sizes and substrate materials are investigated and optimal antenna parameters are achieved. Then, the antenna performance is further enhanced by inserting single and double slot designs into the patch. Two cost-effective feeding methods are involved in the investigation. The antenna is designed to operate in the Super High Frequency (SHF) band.