Integrated photonic ultrawideband real-time spectrum sensing for 6G wireless networks

This paper presents a novel integrated photonic real-time spectrum sensing (RT-SS) system designed to address the challenges of spectrum management for 6G wireless networks, particularly in the dynamic spectrum sharing (DSS) required for integrated sensing and communication (ISAC) applications. The proposed system, based on a thin-film lithium niobate (TFLN) platform, enables ultrawideband spectrum measurement from microwave to sub-terahertz bands with low latency and high temporal resolution.

Key findings include:

1. System Design: The RT-SS system integrates electro-optic (EO) modulators, a tunable microring filter bank, and an EO comb for precise channel frequency referencing, all implemented on a single photonic chip. This allows for ultrabroadband spectrum measurement up to 120 GHz with a low latency of less than 100 ns.

2. High-Performance Spectrum Sensing: The system demonstrates real-time frequency-to-time mapping (FTTM) with high speed and precision. The use of a channelized measurement architecture, driven by an EO comb, enables the system to recover the full spectrum of signals while maintaining high accuracy even for fast-changing spectrum environments.

3. Latency and Resolution: The system achieves an unprecedented spectral analysis range and provides frequency resolution of 350 MHz, with a temporal resolution of 100 ns, making it suitable for real-time dynamic spectrum management in 6G networks.

4. ISAC Demonstration: The paper showcases a proof-of-concept ISAC demonstration where a radar and communication system dynamically share the same frequency band. The radar accesses underutilized spectrum regions, avoiding interference from the communication system, which improves the signal-to-interference-plus-noise ratio (SINR) for radar sensing.

5. Applications for 6G Networks: The proposed photonic RT-SS system provides a compact, cost-effective solution for efficient spectrum sharing and dynamic resource allocation in future 6G networks. It supports both radar sensing and communication in a shared spectrum environment, enabling the coexistence of these systems without interference.

In conclusion, this work presents a significant advancement in spectrum sensing and management for 6G wireless networks, highlighting the potential of integrated photonic solutions to meet the high-performance requirements of dynamic spectrum access in future ISAC applications.