Design of 8-Elements Linear Dipole Antenna Array to Suppress Sidelobe Signals by Using Genetic Optimization

High sidelobe levels can result in unwanted interference or "noise" from signals arriving from directions other than the desired main lobe. These signals can degrade the overall performance of a system by reducing the signal-to-noise ratio, making it more difficult to distinguish the intended signal from background noise. In systems like radar or satellite communication, sidelobes can cause interference to other users or systems operating in adjacent frequency bands or directions. Suppressing the sidelobes helps minimize this cross-talk and interference. When the sidelobes are suppressed, more of the transmitted power is concentrated in the main lobe, improving the efficiency of power usage. This is important in communication systems where conserving power is essential, such as in satellites or mobile devices. In environments where signals may bounce off objects (such as in urban areas for wireless communication or radar), sidelobes can pick up signals reflected from various surfaces. By suppressing sidelobes, the system becomes less susceptible to multipath interference, which can degrade signal quality and accuracy. To sum up, sidelobe suppression is crucial for ensuring the efficiency, accuracy, and reliability of many systems, particularly in radar and communications. It minimizes interference, reduces false detections, improves directional sensitivity, and ensures that resources (e.g., power and bandwidth) are used effectively. In this paper, 8-element linear dipole antenna array designed to suppress sidelobe signals, which causes interference on the communication system. One of the key parameter is the distance between the each antenna. In this simulation, we defined the distance between each antenna as 0.6*lambda, for 3GHz operating frequency. Another optimization parameter is the magnitude of each antenna element, aimed to optimize magnitudes of each antenna element's sidelobe levels by using Genetic Algorithm (GA), where theta angle between 40-60 degrees. The antenna array design done in CST Studio environment, but amplitude tuning with GA performed using MATLAB. We compared our design results for each simulation, observed the change of directivity for antenna array by using GA. As a result, the sidelobe level between the desired theta 40 and 60 degrees suppressed from -17dB to -28.2dB but it observed that the directivity of the main antenna radiation pattern decreased from 13dBi to 10dBi.