Hybrid Phased Array Antenna System for High Data Rate mm-Wave Wireless Communication (HyPAA)

• Applicants: Professor Dr.-Ing. Dietmar Kissinger; Professor Dr.-Ing. Holger Maune
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 320392473

The aimed project addresses the challenges faced, when exhibiting high data rate mobile wireless communication links in the millimeter-wave band. The increase in free-space path loss and oxygen absorption in combination with a large bandwidth leads to a very stringent link budget. To achieve a reasonable high signal to noise ratio, the use of high gain antenna systems is inevitable. However, highly directive communication links necessitate for the ability to dynamically adjust the orientation of the antennas main beam. Thereby, the trend is towards replacing any mechanical component by electronic steering mechanisms. Mechanically steered antennas are in general bulky, heavy, maintenance intensive and hence costly, making them unattractive for mobile applications and consumer products. However, the implementation of a phased array system comprising NxM array elements with the same amount of independent RF channels in order to apply the necessary phase and amplitude weighting in the baseband is as well complex, bulky and cost intensive. A more promising approach is to perform the phase weighting in the RF domain utilizing passive phase shifters, which reduces the amount of independent RF channels. This project focuses on the innovative application of liquid crystal as tunable material together with active components for the realization of hybrid array antenna systems. Here, one challenge lies in the requirements placed on the phase shifting component. Due to their assignment to each array element, they have to be that compact to fit behind one antenna. At the same time, they are required to be compact, flat and low-loss to meet the overall requirements for mobile applications. Further, the phase shift introduced has to be large enough to cover the angular steering range for the specific application. Although the low-loss properties of LC, it is still difficult to meet the above mentioned criteria altogether, especially concerning the losses. Therefore, this project aims for a new approach by combining, for the first time, active components and tunable passive LC phase shifters to diminish the strong requirements placed on the phase shifters. Further, the integration of variable gain amplifiers in such a system enables the possibility for full beam synthesis (i.e. phase and amplitude weighting).To accomplish the above mentioned goals, a systematic technique to design hybrid/active phased arrays will be developed. The passive phase shifters will be realized in innovative and promising low-loss LC technology. Transceiver ICs will be integrated and packaged into the antenna panel in order to increase the system performance in terms of SNR, size and power consumption. The challenges will be, to incorporate this concept into the design procedure as well as the integration of active with LC based passive components.

• DFG Programme: Research Grants