F. Scotti

Field trial of the first photonic-based radar for maritime border security and harbor protection

The field trial results of the first photonics-based radar system in a real maritime environment are presented in this paper. The exploited prototype is the final outcome of the ERC-funded project PHODIR (PHOtonics-based fully DIgital Radar). The system exploits photonic technologies for both the generation and the detection of radar RF signals, allowing increased performance and an unprecedented potential flexibility. This paper details the system capabilities and presents the field trial campaign conducted at the port of Livorno (Italy), detecting naval targets on both long range and harbor maneuvering. The results prove the effectiveness of the proposed scheme and the benefits of photonics highlighting the excellent performance and promising improvements.

A software-defined and filter-free 0–26.5 GHz ultra-wideband RF transmitter enabled by photonics

An innovative software-defined photonics-based RF transmitter is presented. Stemming from a single widely tunable up-converting stage, the architecture exhibits large instantaneous and operating bandwidths, and avoids bulky RF components like synthesizes, multiple mixers and bandpass Alters. A dual-use scenario (radar plus communication) is created in laboratory, where an operative bandwidth from near DC up to 26.5 GHz is experimentally demonstrated. Laboratory constraints limited the total current bandwidth that in principle can be extended up to 40GHz and beyond, exploiting commercially available electro-optical devices with better performance. The transmitter has reached a carrier leakage suppression and a sideband suppression greater than 45 dB, exceeding the preperformance of the filter-free electronic counterparts. The system also presents high linearity and dynamic range in terms of linear dynamic range (141 dB/Hz) and an IMD3-limited spurious free dynamic range (107 dB/Hz2/3). In addition, photonic integration will provide a chip-scale solution with improved compactness and environmental stability.

Software defined coherent lidar (SD-Cl) architecture

In recent years, thanks to the innovation in optical and electro-optical components, space based light detection and ranging (Lidar) systems are having great success, as a considerable alternative to passive radiometers or microwave sensors [1]. One of the most important applications, for space based Lidars, is the measure of targets distance and its relative properties as e.g., topography, surfaces roughness and reflectivity, gravity and mass, that provide useful information for surface mapping, as well as semi-autonomous landing functionalities on lowgravity bodies (moons and asteroids). These kind of systems are often called Lidar altimeters or laser rangefinders.

Microwave photonics for Integrated multifrequency lidar / radar system

Surveillance systems, both based on radio frequencies (Radio Detection and Ranging: radar) and optical signals (Light Detection and Ranging: lidar), are evolving toward multiband multifunctional systems that are putting electronic technologies under pressure. Thanks to its intrinsic high stability, ultra-wide bandwidth, low loss propagation, EMI insensitivity, and high frequency of the optical carrier, photonics can be exploited not only for optical systems but also for facing these new requirements in RF systems. In fact, microwave photonics technologies play a crucial role in the generation of very stable multi-band radiofrequency (RF) sources, and in very precise and wideband RF signal detection and digitization, guaranteeing a higher level of flexibility and reconfigurability, and the complete software-defined configuration of radar systems. At the same time they allow to implement multifrequency lidars able to synthesize tunable RFs on optical carriers, for the exploitation of RF radar techniques in lidar systems. Moreover solutions based on integrated photonic circuits allow for a reduction of power consumption and footprint thanks to the subsystems implementation on a chip.

Aerial field trial of the first photonics-based fully digital radar prototype

The field trial results of the first photonics-based fully digital radar system are presented. The system has been developed in the PHODIR project, and is tested here in a real aerial scenario with non-cooperative targets. The innovative radar is described, and the results are presented and discussed.