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Laser-based data links are increasingly attractive for aircraft and space systems that need to move large volumes of information quickly. Free-space optical communication (FSOC) offers high bandwidth and resistance to radio-frequency congestion, but it comes with a practical limitation: maintaining full 360-degree coverage. Today, that typically requires multiple steerable laser terminals mounted around an aircraft’s fuselage, adding complexity, weight, and power demands that are difficult to accommodate, especially on high-altitude platforms.
A recent study suggests an alternative approach that could reduce this burden. Instead of equipping an aircraft with several complete laser terminals, researchers explored the use of optical fiber bundles to route incoming laser signals from small external collectors to a single internal laser communication terminal. In this architecture, light captured at different points around the airframe is guided through fiber bundles to a central receiver, minimizing duplication of hardware.
To evaluate the concept, the research team tested a commercially available fiber bundle at the standard FSOC wavelength of 1550 nanometers. The experiments focused on how the bundle affected signal quality, measuring optical losses, distortion, and performance under simulated turbulent air-to-air conditions. These tests allowed the researchers to quantify how fiber bundles influence key receiver metrics when compared to a conventional direct optical path.
For defense and homeland-security applications, such an approach could be particularly relevant. Secure, high-capacity communications between airborne platforms, satellites, and ground stations are a critical requirement for surveillance, command-and-control, and data relay missions. FSOC systems are attractive in contested environments because they are difficult to intercept and do not contribute to radio-frequency congestion. Reducing the number of external laser terminals needed for full coverage could make these systems easier to integrate on aircraft operating at high altitude or long endurance.
According to TechXplore, the results showed that fiber bundles can function in an FSOC receiver, but also highlighted current limitations. The tested bundle was designed for visible wavelengths rather than the short-wavelength infrared band used in FSOC, which led to notable signal penalties. The researchers emphasize that bundles fabricated from materials optimized specifically for the C-band would be needed to achieve better performance.
Looking ahead, the team points to further work on fiber materials, fabrication techniques, and full system architectures. This includes developing transmission and multiplexing components capable of managing multiple incoming optical signals. While additional development is required, the study establishes a technical foundation for distributed FSOC receivers that rely on fiber bundles, potentially offering a more compact and efficient way to support laser communications on future airborne platforms.
The research was published here.
