Microstrip arrayed lines lens for microwave beam steering

This talk introduces an on-chip realization of the discrete fractional Fourier transform (DFrFT), proposed and experimentally implemented in the microwave domain utilizing a passive metamaterial coupled lines network (MCLN). This renders a lensless device capable of performing the DFrFT in real-time. The MCLN comprises N microstrip transmission lines coupled to their nearest neighbors through an array of interdigital capacitors composed of interlaced microstrip fingers. In the latter, the dimension and number of fingers allow for controlled and enhanced coupling terms that render the required DFrFT couplings highly accurate. The MCLN is exploited to design a new compact planar electromagnetic lensless solution that enables a beam steering operation through the focal plane array concept. The latter is performed by independently exciting the input ports of the MCLN through a switch tree, while the output ports are connected to an antenna array to realize a focal plane array system. Contrary to other approaches, this device does not require any external phase element, reducing the overall power consumption.