Cost-Effective 4×4 3D Printed Interdigital Fed SRR Based MIMO Antenna for IoT Application

A novel 4×4 3D-printed Multiple Input Multiple Output (MIMO) antenna, incorporating Split Ring Resonators (SRRs), is designed and analyzed for Internet of Things (IoT) applications. Each individual antenna element features an innovative structure, consisting of a modified “W” radiator integrated with SRRs and a microstrip-fed interdigital feed line. The array of four antennas is symmetrically arranged on a flexible Ninjaflex substrate, with a compact footprint of 83×83× 0.2 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> (0.66λ×0.66λ×0.0064λ at the lowest resonating frequency of 2.4 GHz). The proposed MIMO antenna demonstrates wideband performance across multiple frequency bands, offering impedance bandwidths of 16% (2.23 – 2.62 GHz), 13.53% (3.65 – 4.18 GHz), and 25.57% (5.73 – 7.41 GHz) with −10 dB reflection coefficient. It achieves an impressive peak gain of 4.86 dBi and an operational efficiency of 86.73%. Moreover, the antenna’s design enables a channel capacity of 17.83 b/s/Hz, enhancing the reliability and throughput for IoT communication systems. The antenna’s design combines compactness, high performance, and wide frequency coverage, making it a promising candidate for next-generation IoT applications that demand reliable communication across various bands.