# Taguchi Method-Based Synthesis of a Circular Antenna Array for Enhanced IoT Applications
###### Abstract  
Linear antenna arrays exhibit radiation patterns that are restricted to a half-space and feature axial radiation, which can be a significant drawback for applications that require omnidirectional coverage. To address this limitation, the synthesis method utilizing the Taguchi approach, originally designed for linear arrays, can be effectively extended to two-dimensional or planar antenna arrays. In the context of a linear array, the synthesis process primarily involves determining the feeding law and/or the spatial distribution of the elements along a single axis. Conversely, for a planar array, the synthesis becomes more complex, as it requires the identification of the complex weighting of the feed and/or the spatial distribution of sources across a two-dimensional plane. This adaptation to planar arrays is facilitated by substituting the direction \(\theta\) with the pair of directions \((\theta,\phi)\), allowing for a more comprehensive coverage of the angular domain. This article focuses on exploring various configurations of planar arrays, aiming to enhance their performance. The primary objective of these configurations is often to minimize the levels of secondary lobes and/or array lobes while enabling a full sweep of the angular space. Secondary lobes can significantly impede system performance, particularly in multibeam applications, where they restrict the minimum distance for frequency channel reuse. This restriction is critical, as it affects the overall efficiency and effectiveness of communication systems that rely on precise beamforming and frequency allocation. By investigating alternative planar array designs and their synthesis methods, this research seeks to provide solutions that improve coverage, reduce interference from secondary lobes, and ultimately enhance the functionality of antennas in diverse applications, including telecommunications, radar systems, and wireless communication. Taguchi method; circular antenna array; IoT applications; radiation pattern +
Footnote †: journal:  
0000-0001-5000-4999-2233]W. A.  
sectors, including smart homes, industrial automation, healthcare, and smart cities. This proliferation of IoT applications demands robust and efficient communication systems capable of supporting a vast array of devices while ensuring seamless connectivity and reliable performance. Among the critical components influencing the efficiency of these wireless communication systems are antenna arrays, which are instrumental in determining coverage, radiation patterns, and signal integrity. The synthesis of radiation patterns for linear planar antenna arrays is a crucial topic in antenna engineering. A linear planar array consists of antennas arranged in a line, enabling the generation of directional and controlled radiation patterns. These radiation patterns, which illustrate how energy is distributed in different directions, are essential for evaluating an antenna's effectiveness in various applications. Several techniques, such as the least squares method, Taguchi method, and genetic algorithms, are employed to optimize the amplitudes and phases of the antenna signals to achieve the desired pattern. These arrays are particularly used in wireless communication systems, radar, and localization systems, including in Multiple Input Multiple Output (MIMO) systems to enhance transmission capacity [1]. However, this approach has certain drawbacks. Managing interference between antennas can be complex, potentially degrading signal quality. Additionally, designing and manufacturing complex antenna arrays require high costs and resources, which can limit their implementation in some contexts. Furthermore, the performance of the arrays can be affected by environmental factors, such as the presence of obstacles, necessitating constant adjustments to maintain efficiency. Despite these challenges, by combining optimization methods and advanced design techniques, it is possible to create effective antenna arrays that meet the demands of modern applications.