Prof. Stefano Tomasin

Open Post-Doc Positions

1) Physical layer security for underwater communication networks

Required expertise: communications systems, signal processing for communications. Some previous research activity on physical layer security is appreciated.

Start date: as soon as possible.

Duration: 1 year.

Project abstract: Underwater acoustic communications (UWAC) is increasingly perceived as a cost-effective ocean exploration and monitoring means. However, while carrying out these tasks, UWAC devices are left unattended over long periods of time and may become vulnerable to external attacks. The recent introduction of NATO standards for UWAC, JANUS, makes these attacks more probable. We propose to explore new ways to secure UWAC against attackers. Our solutions eliminate the need to change existing modems or include encryption systems, and rather provide a protective layer that can be added to any modem, thereby offering a practical solution to underwater cybersecurity.

Project Description: The underwater channel’s spatial dependency and the long propagation delay offer a diversity gain that can enable the exchange of secret cryptographic keys; the complex mobility patterns of drifting nodes and the time-varying channel impulse response convey information that could help prevent interception attacks; and the strong attenuation leads to sparse communication links that improve topology diversity, thereby increasing security by subdividing data communications among different, disjoint wireless links. In this project, we aim to design a complete cybersecurity framework for underwater acoustic communications. We will provide novel and practical solutions in the fields of message authentication, secret key exchange, analysis of bounds for low probability of detection and low probability of interception, to design general interception techniques for existing security solutions, to be coalesced into a broadly shared benchmark to test future secure communications systems. With the goal of improving exploitation opportunities, we will focus on solutions that build upon existing underwater acoustic communication (UWAC) modems, providing a full security envelope for UWAC devices, rather than intervening in the modem’s design.

2) 5G Fronthauling with Multimodal Optical Fiber

Required expertise: communications systems, signal processing for MIMO communications. Some previous research activity on resource allocation and optimization is appreciated.

Start date: flexible, preferably by Dec. 2021.

Duration: 1 year

Project abstract: For fifth- and sixth-generation cellular networks we envision that the radio base station (BS) is connected to the central office by an optical link. The project will investigate the use of few mode fibers (FMFS) for this link (this part will be performed by another research group). At the BS, for downlink, the signal received over the filter will be processed by a a simple analog reconfigurable beamforming before transmissions on a large number of antennas; similarly, received signals are combined by an analog reconfigurable device before transmission (in digital) over the fiber. This beamformer/combining operation supports the exploitation of multiple antennas for steering the signal in specific direction, while reducing the required fiber data rate. Resource allocation algorithms will be considered for specific 5G applications having rate and latency requirements, in particular highly demanding services such as e-health and mobile health services.

Specific activity of the researcher: The research will propose new solutions for resource allocation and analog beamforming solutions over the radio access link, taking into account the constraints on the front-haul segment implemented by the optical link.

More News on Linkedin.

View Stefano Tomasin's Google Scholar profile