Objective To address the issues of insufficient communication capacity, weak anti-interference capability, and low space utilization in ship communications, a flexible millimeter-wave multiple-input multiple-output (MIMO) antenna suitable for 5G communication was designed.

Method The antenna design innovatively arranges the elements orthogonally on a flexible polyethylene terephthalate (PET) substrate, achieving a compact size of 68 mm×68 mm×0.12 mm that overcomes the limitations of conventional rigid antennas. Each antenna unit employs a circular monopole structure with an arc-truncated ground plane to optimize the coplanar waveguide (CPW) feeding configuration. The orthogonal arrangement effectively suppresses mutual coupling while successfully covering the key frequency bands for 5G millimeter-wave communications. The prototype was fabricated using screen-printed copper conductive paste, ensuring both low-cost manufacturability and excellent flexibility. Mechanical stability was verified through bending tests, with performance remaining consistent at curvature radii of R≥20 mm.

Results Simulation and test results showed that the antenna operated in the frequency band of 26～32 GHz, with an isolation level below −36 dB, an envelope correlation coefficient of less than 0.000 15, and a diversity gain greater than 9.999 dB.

Conclusion The proposed antenna leverages the high bandwidth characteristics of the millimeter-wave frequency band and the multi-stream transmission capability of MIMO technology, significantly enhancing communication performance. Its flexible design facilitates flexible deployment in complex ship environments, optimizing signal coverage and space utilization, and providing an efficient and reliable solution for ship communication systems.