Design of an on-chip antenna array for Direction of Arrival Estimation applications in Sub-THz frequency range

In the recent years, Sub-THz radar applications are thoroughly investigated because of specific properties of the electromagnetic waves at these frequencies. Moreover, in this frequency range the possibility to use a large bandwidth leads to a high range resolution for FMCW Radar applications, and hence to the possibility to realize new radar sensors with enhanced capabilities. For frequencies greater than 300 GHz the wavelength in free space is less than 1 mm, which allows the implementation of one or more antennas on chip. In such way, it is possible to avoid losses caused by the interconnection between chip and external antennas. However, on-chip antenna design is a challenging task as a number of physical factors affects the efficiency of the antenna itself. Several solutions to this problem have been proposed in the literature, among them it is worth mentioning the use of external dielectric resonators and the use of superstrates to be placed on the top of a coupling structure realized on the chip. On the other hand, these solutions are usually prone to positioning errors that occurs in the assembly phase. In particular, the effect of a positioning error is to shift the antenna phase centre as well as to reduce the efficiency of the antenna. When considering to implement an array of antennas for Direction of Arrival (DoA) estimation, a tolerance on the antenna phase centre positions may affect the performance of the whole array.

The key focus of this thesis is the design of an antenna structure that addresses the positioning error issue for the implementation of an antenna array on chip for DoA estimation, while meeting the requirements in terms of bandwidth and gain as well as efficiency.

In the first part of the work a literature review is required. Afterwards, the design of a single radiator and an analysis of the coupling effect between two or more antennas will be performed using 3D electromagnetic simulator. Finally, the antenna array positions will be optimized using MATLAB and, upon the outcomes of the optimization, the final array will be designed and investigated through CST Microwave Studio.

As for prerequisites, it is strongly advised to be familiar with the use of a 3D electromagnetic software (e.g. CST Microwave Studio, Ansys HFSS) and MATLAB. Moreover, a strong understanding of the concepts of the course “Propagation and Antenna” is required.

Tasks may be modified according to the progress of work.