The thesis, submitted by Noor Waadallah Yaseen Al-Zaidi to the Department of Communications Engineering at the College of Electronics Engineering, focuses on the enhancement of the radiation performance of digital antenna arrays by deactivating certain elements. This approach aims to reduce cost, weight, complexity, power consumption, and heat dissipation in arrays where all elements are active, while maintaining optimal system performance by preserving the antenna’s characteristics using various techniques such as the Random Thinned Method and Iterative Fourier Transform Method.
The thesis proposes an effective improvement method based on a genetic algorithm and dynamic deactivation to randomly deactivate a number of array elements, thereby reducing the side lobe level of the proposed method while preserving the array’s directivity without distortion. The research also investigates the performance of scanned main beams at various angles with some elements deactivated, comparing the enhanced GA method with the performance of a fully active array.
The objective of the thesis is to optimally select the number and locations of deactivated elements to positively alter the radiation characteristics according to a specified cost function. The proposed improved algorithm showed very good performance when a small number of thinning elements were selected, ensuring minimal impact on the array’s performance, though performance declined when the number of thinning elements increased significantly, requiring more time to find optimal solutions.
The discussion committee consisted of :
- Asst.Prof. Dr. Ali Othman Mohammed (Chairman) .
- Asst.Prof. Dr. Ahmed Mohammed Salama . Member.
- Asst. Prof. Dr. Yasir Ahmed Fadhel . Member
4.Prof.Dr. Jaafar Ramadan Mohammed ( member and supervisor).
