Reshaping the antenna: VTT's transmitarray technology for the 6G era

At VTT, transmitarray research is part of a broader effort to shape the future of wireless communication. As digital services expand and more devices depend on fast connections, wireless systems are moving toward higher frequencies where more data can be carried. At the same time, these frequencies introduce new challenges, and familiar antenna solutions become both inefficient and difficult to scale. VTT’s work advances technologies that meet these conditions while maintaining high performance and practical scalability.  

The transmitarray concept developed at VTT reflects a new way of building antennas. Instead of guiding signals through a dense and complex internal network, a signal is radiated toward a flat surface. This surface consists of many small elements, each receiving the signal, adjusting it and sending it forward again. Every element controls the phase and strength of the signal locally, and together they form a coordinated system that produces a focused and directed beam. The antenna behaves as a unified, intelligent surface rather than a structure defined by internal wiring.  

At high frequencies, this approach aligns well with the physical behaviour of signals. Local control at each element removes the need for long transmission paths inside the antenna, while maintaining a strong and well defined beam. Large antenna apertures become feasible in an efficient form, enabling high capacity wireless links with reliable performance.  

The lower loss architecture compared to traditional ones supports more energy efficient wireless links, reducing power consumption and contributing to greener communication technologies while improving performance and reliability. 

Electronic beam steering defines another key capability of the transmitarray. By adjusting how individual elements modify the signal, the system directs energy in different directions without any mechanical movement. The beam remains narrow and precise, enabling long range communication and reducing interference. This level of control enables adaptable and responsive wireless systems suited for dynamic environments.  

VTT’s implementation highlights manufacturability and modularity. The antenna is constructed from repeating building blocks, i.e. stacked boards that form a two dimensional array. This structure allows straightforward scaling, with larger systems formed by adding more layers of identical modules. The design also supports effective heat dissipation, which is important when active electronics are integrated into every element.  

These characteristics enable a wide range of advanced applications. High capacity point to point wireless links provide an alternative to fibre connections in environments where cable deployment is limited. Future 6G networks rely on highly directional antennas to deliver fast and efficient connectivity to many users simultaneously. Satellite systems benefit from flat, lightweight and electronically steerable antenna panels. 

Precise control of electromagnetic waves also enables advanced sensing technologies, including radar systems that require accurate beam shaping.  
Through this work, VTT advances a technology that combines efficient free space signal propagation with fine electronic control at the element level. The result is a scalable and high performance antenna solution that supports strong, targeted and adaptable wireless communication for future systems. For Finnish industry this gives an early foothold in technologies set to define the next generation of wireless networks.