Researchers have created a 3D-printed device capable of producing twisting light beams that carry orbital angular momentum (OAM). This type of rotational energy can transmit significantly more information than traditional light beams. The compact, efficient, and economical vortex beam generators have the potential to improve the capacity and dependability of future wireless communication technologies.
Researchers have created a 3D-printed device capable of producing twisting light beams that carry orbital angular momentum (OAM). This type of rotational energy can transmit significantly more information than traditional light beams. The compact, efficient, and economical vortex beam generators have the potential to improve the capacity and dependability of future wireless communication technologies.
“The increasing need for high-capacity, interference-resistant communication systems, especially in areas like 5G and 6G networks, calls for creative solutions,” explained Jianxing Li, the lead researcher from Xi’an Jiaotong University in China. “While OAM-carrying vortex beams can boost communication capacity and spectral efficiency, current generation methods are hampered by low efficiency, high production costs, and susceptibility to interference from other frequency bands.”
In the journal Optics Express, the research team discusses how they utilized 3D printing technology to develop an OAM beam generator designed as a sophisticated antenna system for advanced wireless communications. This device produces high-capacity vortex beams and includes a built-in gain-filtering system that enhances desired signals while blocking interference, ensuring efficient and clear transmission.
“Our OAM beam generator is particularly ideal for 5G and 6G communication, as well as remote sensing and imaging,” remarked Yuanxi Cao, the paper’s corresponding author. “For instance, using this device in communication towers could enhance streaming and connectivity during large events such as music festivals or sports matches, where high user density can overwhelm existing networks, leading to slow speeds and dropped connections.”
Integrated signal filtering
The innovative 3D-printed OAM beam generator incorporates a built-in gain-filtering power divider that evenly splits the signal while filtering out unwanted frequencies right at the source. This process helps limit interference and reduces the necessity for extra external components. Additionally, the researchers designed an air-filled all-metal structure to minimize dielectric losses for improved radiation efficiency and increased power-handling capability.
The device functions by initially separating an incoming signal into eight equal parts via the built-in power divider, which simultaneously filters out unnecessary frequencies. Each segment then travels through a specialized pathway that modifies the phase to achieve the precise alignment needed for creating a vortex beam. In the end, these segments are sent through a circular array of antennas, producing a vortex beam with the required characteristics.
Fabrication and testing
After conducting advanced simulations to optimize the filtering power divider for accurate in-band signal transmission and effective out-of-band suppression, the researchers employed selective laser melting to 3D print a prototype using an aluminum alloy recognized for its precision and smooth surface finish.
“We built the device as a single structure using selective laser melting 3D printing technology,” said Cao. “This approach removes the need for assembly, lowering manufacturing costs and ensuring precise component alignment—all of which are vital for high-frequency applications.”
Experimental results demonstrated that the prototype device achieved the desired beam properties, reaching a mode purity of about 80%. It also showcased excellent out-of-band suppression greater than 30 dB, considerably reducing interference and ensuring a clean signal transmission.
The team is currently focused on improving the performance of the OAM beam generator by enhancing its gain, efficiency, and signal filtering capabilities. They also aim to broaden its applications by investigating multi-mode OAM generation and testing it across wider frequency ranges, including terahertz communication. Researchers note that commercializing the device will necessitate refining the 3D printing process for scalability, integrating it with existing systems, meeting regulatory standards, and validating its performance in real-world applications such as 5G and satellite communication.
