The SPACEBEAM Project final aim is the design, realization, and test of a spaceborne photonics-assisted SCan-On-REceive Synthetic Aperture Radar (SCORE SAR) receiver for Earth observation application, capable of employing multiple reconfigurable beams. The core of the receiver will be implemented by a hybrid photonic integrated circuit (PIC), able to comply with the requirements of future low-Earth orbit satellites and cubesats in terms of performance, size, weight, power consumption and cost, the envisioned receiver will be based on an optical beamforming network realized as a photonic integrated circuit (PIC). The PIC will implement a precise, continuous beamforming of wideband signals (>600MHz) from a reflector antenna feeder array of 12 elements into 3 separated beams, with the capability to flexibly change the set of employed array element per beam, as well as the number of output beams (from 3 beams of 4 elements each, to 2 of 6, to 1 of 12). At the same time, the PIC will also realize a frequency-agnostic photonic down-conversion of signals in the range from 5 to 40 GHz, down to 1.5 GHz, so that the output signals can be directly digitized. These innovative features make the SPACEBEAM PIC a powerful device for future Earth observation applications.
The PIC will be implemented using two materials platforms, InP and TriPleX™, to achieve a compact “hybrid” chip-assembly including several active and passive functions (lasers, detectors, modulators, filters, switches, delays, phase shifters). The PIC will be controlled using a novel actuation technique based on low-power consuming piezo elements. In order to push forward the maturity of the SPACEBEAM technology (target TRL 6), the project will also develop and test a Space-compliant package for the PIC. The packaged PIC will be included in a specifically designed Elegant Breadboard (EBB) of the multi-beam SCORE-SAR sensor, to properly test the performance of the entire system. The photonics-based SCORE SAR system will therefore show more functionalities, better performance, and lower size, weight, and power consumption than the current systems.