arXiv subjects
Publications and source records attributed to Ivana Gasulla.
Space-division multiplexing optical fibers can provide not only parallel channel transmission but also parallel distributed signal processing, being this a feature particularly attractive in Microwave Photonics applications. We present here few-mode fiber links with tailored modal propagation and dispersion properties that operate as sampled true time delay lines for radiofrequency signals.
Despite Space division multiplexing fibers were initially envisioned as pure transmission media, they exhibit as well great potential for signal processing. We review here different solutions we developed for microwave signal processing devices and links.
We review the recent advances reported in the field of integrated photonic waveguide meshes, both from the theoretical as well as from the experimental point of view. We show how these devices can be programmed to implement both traditional signal processing structures, such as finite and infinite impulse response filters, delay lines, beamforming networks as well as more advanced linear matrix optics functionalities. Experimental results reported both in Silicon and Silicon Nitride material platforms will be presented. We will also discuss the main programming algorithms to implement these structures and discuss their applications either as standalone systems or as part of more elaborated subsystems in microwave photonics, quantum information and machine learning
Here, we review present and future work in the next photonic IC generation aiming at integration of multi-functional software-defined systems for signal processing operations.
We report a model to evaluate the performance of multiple quantum key distribution (QKD) channel transmission using spatial division multiplexing (SDM) in multicore (MCF) and few-mode fibers (FMF). The model is then used to analyze the feasibility of QKD transmission in 7-core MCFs for two scenarios of practical interest. First for transmission of only QKD channels, the second for simultaneous transmission of QKD and classical channels. In the first case, standard homogeneous MCFs enable transmission distances per core compatible with transmission parameters (distance and net key rate) very close to those of single core singlemode fibers. For the second case, heterogeneous MCFs must be employed to make this option feasible
We report the first experimental demonstration of multi-cavity optoelectronic oscillators where the different cavities are hosted in a single multicore fiber. Different configurations are implemented on the same 20-m 7-core fiber link, exploiting both unbalanced dual-cavity operation (loop lengths are a multiple of a reference value) and multi-cavity Vernier operation (loop lengths are slightly different).
We report the experimental evaluation of bending and twisting effects on the propagation and radiofrequency signal processing performance of multicore fibers. We demonstrate that twisting minimizes to a large extend the group delay fluctuations over a bent multicore fiber.
We envision the application of optical Space-division Multiplexing (SDM) to the next generation fiber-wireless communications as a firm candidate to increase the end user capacity and provide adaptive radiofrequency-photonic interfaces. This approach relies on the concept of fiber-distributed signal processing, where the SDM fiber provides not only radio access distribution but also broadband microwave photonics signal processing. In particular, we present two different SDM fiber technologies: dispersion-engineered heterogeneous multicore fiber links and multicavity devices built upon the selective inscription of gratings in homogeneous multicore fibers.
We review our last work on dispersion-engineered heterogeneous multicore fiber links designed to act as tunable true time delay lines for radiofrequency signals. This approach allows the realization of fiber distributed signal processing in the context of fiber-wireless communications, providing both radiofrequency access distribution and signal processing in the same fiber medium. We show how to design trench-assisted heterogeneous multicore fibers to fulfil the requirements for sampled true time delay line operation while assuring a low level of crosstalk, bend sensitivity and tolerance to possible fabrication errors. The performance of the designed radiofrequency photonic delay lines is evaluated in the context of tunable microwave signal filtering and optical beamforming for phased array antennas.
We present how to implement fiber-distributed signal processing in the context of fiber-wireless communications by using different multicore fibers, providing both radio access distribution and microwave photonics signal processing in the same fiber medium.