Space-time Modulated Electromagnetic Metasurfaces for Multi-functional Energy-Efficient Wireless Systems

Job description: Next-generation wireless networks envision an unprecedented densification and an efficient use of the frequency spectrum in the near-millimeter-wave range (17-31 GHz). This context poses an urgent need for disruptive solutions enabling the minimization of the number of transceivers and their individual power consumption. Pioneering works have recently shown that a periodic temporal and spatial modulation of the scattering properties of a sub-wavelength antenna array (metasurface) allow it to transcend the fundamental limits of linear time-invariant (LTI) systems. Therefore, space-time modulated metasurfaces (STMMs) can enable functions which currently require active circuits and/or magnetic components, such as independent programmable beam-forming at different frequencies and non-reciprocal behavior in transmission and reception. The objective of the Ph.D. thesis is to investigate theoretical and practical capabilities of STMMs. Numerical models relating the fields scattered by an STMM excited by an external feed to its homogenized parameters will be developed. Procedures for jointly optimizing space and time modulation laws will enable the simultaneous control on the spatial and frequency spectra of radiated fields in far- and near-field zone. Electrically large antenna prototypes will be designed using switches or p-i-n diodes to control the response of the STMM elements and minimize the overall power consumption, leveraging the background of the laboratory on electronically reconfigurable electromagnetic surfaces. Designs optimized to achieve high-gain harmonic beam-steering and enhanced aperture efficiency will be experimentally tested to assess the potential technology for future applications.

Your profile: M.Sc. in Electronics/Telecommunication Engineering or Applied Physics