Pin-Fin Heatsink Active Antenna Array With Joint Bandwidth Improvement, Footprint Miniaturization and Cooling Benefits

Abstract

This paper presents a novel heatsink antenna array architecture that addresses electromagnetic (EM) performance, antenna miniaturization, and thermal management challenges in antenna-on-substrate (AoS) configurations. By integrating tilted fin heatsinks onto rectangular patch antennas, the proposed unit element improves convective cooling while maintaining desirable radiation characteristics. A parametric analysis demonstrates that optimizing the fin tilt angle results in an 8% reduction in the resonant frequency, effectively miniaturizing the antenna. To further enhance array performance, complementary split ring resonator (CSRR) walls are introduced between elements.
These structures significantly reduce mutual coupling (from approximately −9 dB to −15 dB) and more than double the impedance bandwidth, increasing it from 3.3% to 7.5%. The results confirm improved radiation performance with a 12.7% operational radiation pattern bandwidth centered at 24 GHz and stable gain across scan angles. On the thermal side, distributed chip placement and enhanced convective paths reduce chip temperatures from 97.3 ◦C to 70.3 ◦C for 1W heat power per chip, and from 171.7 ◦C to 138.9 ◦C for 2W heat power per chip under forced airflow conditions compared to the standard patch array. The proposed dual-functional design provides an efficient and compact solution for future high-power and thermally constrained antenna systems, with promising applications in 5G, radar, and mm-wave communication.