Millimeter-wave 3D-printed filtering power divider with high frequency selectivity and enhanced heat dispersion

In this paper, a 3D-printed filtering power divider with high frequency selectivity and enhanced heat dispersion is proposed in the Ka-band. Based on filter synthesis theory, a meticulous design is implemented for 32 rectangular resonators and their adjacent inductive irises, enabling the simultaneous realization of a 1-to-8 power divider function and an integrated 11th-order filtering response. To enhance heat dispersion performance for high power applications, cooling fins, and cooling slots are strategically incorporated into the filtering power divider. The selective laser melting (SLM) 3D printing fabrication technology is employed for the cost-effective monolithic fabrication of the prototype. The measured results demonstrate that the return loss of the input port is over 12 dB within the frequency range of 27.0–31.4 GHz. The phase and amplitude difference between outputs are less than ±8° and ±0.6 dB. The transmission coefficient is approximately 9.7 dB, indicating an excellent low-loss performance of the 1-to-8 power divider. Beyond the operating bands, the transmission coefficient experiences a decline of over 55 dB/GHz, demonstrating an 11th-order filtering response. The proposed filtering power divider excels in low loss, superior frequency selectivity, and enhanced heat dispersion, promising advancements in high-power millimeter-wave systems.