Photonics targets 6G wireless
Photonic integrated circuits are enabling new approaches to free-space optical links, THz signal generation, beam steering and integrated sensing for next-generation wireless systems.
Integrated photonics is emerging as an enabling technology for next-generation wireless systems, with photonic integrated circuits (PICs) being applied to free-space optical (FSO) communications, 6G and terahertz (THz) links, and integrated sensing and communications (ISAC).
The growing demand for wireless capacity is placing increasing pressure on conventional RF systems.
Network densification, limited spectrum availability, power consumption and the complexity of large antenna arrays are driving interest in photonic approaches that can process and transmit high-frequency signals while reducing system size, weight and power requirements.
In FSO communications, PICs can integrate functions including wavelength-division multiplexing, modulation, routing and detection onto compact optical platforms.
Integrated transmitters and receivers could enable high-capacity, low-latency links for applications including building-to-building, vehicle-to-vehicle and satellite communications, particularly where fibre deployment is impractical.
PICs are also being investigated for high-frequency signal generation for 6G and THz wireless systems. Photonic mixing can generate frequencies that are difficult to produce using conventional electronics, while integrating lasers, modulators and antennas on a photonic platform could support high-bandwidth wireless transmission.
Optical phased arrays (OPAs) provide another route for photonics-enabled wireless systems. By using optical interference to control the direction of light, OPAs can enable electronic beam steering without mechanical components. Combined with multiple-input, multiple-output techniques, such architectures could support higher-capacity wireless links.
The same photonic infrastructure could also support ISAC, an emerging 6G technology that combines communications and environmental sensing. PICs can integrate laser sources, modulators, filters, beamformers and true-time-delay elements, allowing photonic circuitry to generate and process signals for both wireless transmission and sensing.
Despite the potential, several technical barriers remain. Optical coupling losses at the interface between PIC waveguides and external fibres or free-space systems can reduce efficiency, while thermal sensitivity can affect component performance across changing operating environments. Packaging cost and scalability are also significant considerations for commercial deployment.
These challenges will become particularly important for applications such as satellite-to-ground communications, where PICs must operate across demanding environmental conditions.
Continued advances in photonic integration, optical I/O and packaging will therefore be important to translating PIC-enabled wireless architectures from emerging demonstrations into scalable systems.
