The platform implements a 3GPP physical layer configuration for 5G mm waves (FR2) and is designed as a scalable concept based on RF systems on a chip (Xilinx). Array antennas can be selected from a portfolio of different antenna designs (for the band at 28 GHz or broadband for the two bands at 28/40 GHz and 18–43 GHz) depending on the application and are connected to the signal processing via RF chains developed in-house. Fraunhofer IIS’s proprietary firmware implementation includes the generation and reception of 400 MHz wide OFDM carrier signals. This involves implementing various reference signals, and user data can be fed in for transmission. Signal processing is available in the receiver for synchronization, MIMO reception, channel equalization, MIMO CSI reporting, payload extraction and localization.
With our 5G FR2 platform, we can enable our customers and partners to perform tests of various 5G applications in the new mm frequency band and also let them quantitatively experience the band’s special properties. For example, broadband transmissions at high data rates can be made using various antenna concepts and MIMO schemes, or cm-accurate distance measurements can be demonstrated using broadband position reference signals. A wide portfolio of FR2 antenna types is available, including beamforming and sectorized array antennas. This means users can select the best variant for each scenario and application from the perspective of various key performance indicators such as SINR maximization and energy efficiency (minimizing power consumption to reduce the carbon footprint). With calibrated antennas, the FR2 platform also provides a means for mobile direction-resolved radio channel measurements in space, time and frequency (channel sounding). In other words, customers can have the actual propagation characteristics determined in all dimensions for their specific radio environment.
At the moment, the platform can benefit all customers interested in answers to questions of principle and practice on the subject of mm waves, since at this stage it allows over-the-air measurements. So the FR2 platform is especially appealing to users who already want to explore the potential of mm waves in their specific application. But our science partners also benefit from this offering. Our in-house firmware can be flexibly adapted to different measurement and research questions.
The platform is already being used for in-house measurements in the millimeter-wave frequency band. In projects investigating the sustainability of mobile networks, it is used as a model for analyzing and optimizing energy consumption. It is also used to study and develop new physical layer functions for 5G and 6G networks. Together with our customers and partners, we can define projects with new tasks and implement them at any time.