Electronically controllable THz transmitter

• Applicants: Professor Dr.-Ing. Nils Pohl; Professor Dr.-Ing. Christian Waldschmidt
• Subject Area: Communication Technology and Networks, High-Frequency Technology and Photonic Systems, Signal Processing and Machine Learning for Information Technology ; Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 550901470

In this project, a THz transmitter with beamforming for wireless applications is being researched. Highly integrated and lightweight long-range systems are required in various application areas. The high absolute bandwidth for communication and sensor systems as well as the detection of spectroscopic material signatures are the main incentives for THz applications. To enable or improve THz transmitting systems for many of these applications, two different technologies are combined in this project. One is highly integrated silicon-germanium (SiGe) front-end circuits at 0.5 THz and the other is holographic antennas with glass-based assembly and interconnection technology (AVT). SiGe circuits can have very high circuit complexity but are limited in their output power in the THz range. Conventional phased array concepts or dielectric lenses can improve the EIRP of the system but have major problems with scaling the frequency into the THz range or beam steering. Therefore, these circuits are combined with high-gain antennas. Individual antenna elements with spatially overlapping apertures are designed on a glass substrate in the form of holographic antennas for a scalable array, which leads to high aperture efficiencies and thus to a high EIRP. In addition, the antenna beam of a holographic antenna is to be controlled for the first time by a very finely resolved transmission phase, which is provided by precise vector modulator circuits.

• DFG Programme: Research Grants