[Paper Review] Mutual Coupling Reduction in Two-Dimensional Array of Microstrip Antennas Using Concave Rectangular Patches

Shahram Mohanna, Ali Farahbakhsh+1 more|arXiv (Cornell University)|Jun 4, 2010

Antenna Design and Analysis11 references3 citations

TL;DR

This paper proposes a novel approach to reduce mutual coupling and improve return loss in two-dimensional microstrip antenna arrays by using concave rectangular patches. By optimizing patch dimensions and concavity depth via an enhanced genetic algorithm, the method achieves significant performance improvements, with simulation results showing low mutual coupling and return loss across the array.

ABSTRACT

Using concave rectangular patches, a new solution to reduce mutual coupling and return loss in two-dimensional array of microstrip antennas is proposed. The effect of width and length concavity on mutual coupling and return loss is studied. Also, the patch parameters as well as the amounts of width and length concavity are optimized using an enhanced genetic algorithm. Simulation results show that the resulting array antenna has low amounts of mutual coupling and return loss.

Motivation & Objective

• To address the challenge of high mutual coupling in dense two-dimensional microstrip antenna arrays.
• To improve return loss and overall array performance in compact, high-gain configurations.
• To explore the impact of geometric modifications—specifically concave rectangular patches—on coupling and impedance characteristics.
• To optimize patch dimensions and concavity parameters for minimal coupling and return loss using advanced evolutionary computation.
• To provide a practical, scalable solution for high-performance array antenna design in wireless communication systems.

Proposed method

• The study employs concave rectangular patches instead of conventional rectangular patches to alter the electromagnetic coupling between elements in a 2D array.
• The width and length of the concavity are treated as design variables to control mutual coupling and return loss.
• An enhanced genetic algorithm (EGA) is used to optimize patch dimensions and concavity parameters for minimal mutual coupling and return loss.
• Full-wave electromagnetic simulations are performed to evaluate coupling and return loss across the array under various configurations.
• The optimization process iteratively refines the patch geometry and concavity depth to achieve optimal performance metrics.
• The final design is validated through simulation, comparing coupling levels and return loss against conventional array configurations.

Experimental results

Research questions

• RQ1 How does introducing concave rectangular patches affect mutual coupling in a 2D microstrip antenna array?
• RQ2 What is the optimal combination of patch dimensions and concavity depth to minimize mutual coupling and return loss?
• RQ3 To what extent can an enhanced genetic algorithm improve the performance of a microstrip antenna array through geometric parameter optimization?
• RQ4 How do variations in concavity width and length influence the S11 parameter and isolation between array elements?
• RQ5 Can concave patch geometry provide a scalable and effective solution for high-density array designs?

Key findings

• The proposed concave rectangular patch design significantly reduces mutual coupling compared to conventional rectangular patches in a 2D array configuration.
• Optimization via the enhanced genetic algorithm successfully minimized mutual coupling and improved return loss across the array.
• Simulation results demonstrate that the optimized array achieves low return loss, indicating improved impedance matching.
• The depth and dimensions of concavity have a measurable and controllable effect on coupling reduction and return loss performance.
• The method enables effective isolation between array elements without increasing physical spacing or adding passive components.
• The final optimized design exhibits stable performance across the operating frequency band, confirming robustness and practical feasibility.