Electronically Scanned Array Antenna Pattern Simulation: Grating Lobe Analysis and Performance Evaluation

This document presents a comprehensive simulation study of grating lobe behavior in electronically scanned array antennas under different parameter configurations. The investigation focuses on how grating lobes evolve with scanning angle variations, while simultaneously analyzing the dynamic changes in main lobe width and power gain across various operational conditions.

To enhance the technical depth, the simulation employs array factor calculations using MATLAB's phased array toolbox, where the grating lobe formation is modeled through element spacing and phase shift algorithms. Key functions such as phased.ULA (Uniform Linear Array) and phased.SteeringVector are implemented to demonstrate how element spacing exceeding half-wavelength triggers grating lobes. The mathematical foundation incorporates pattern multiplication principles and Fourier transform relationships between element spacing and angular spectrum.

For practical implementation, the code includes scanning angle sweeps from -90° to 90° with incremental phase shifts, calculating directivity patterns using array synthesis techniques. Performance metrics are evaluated through main lobe beamwidth computation (3-dB points) and gain calculations relative to isotropic radiators. The analysis provides crucial insights for antenna array designers in optimizing element spacing and scanning strategies to suppress grating lobes while maintaining desired radiation characteristics in communication systems and radar applications.

This work establishes a robust framework for further research in advanced beamforming algorithms, adaptive nulling techniques, and multi-array configurations, offering practical MATLAB code templates for real-world antenna design validation and performance optimization.