Synesthesia of machine (SoM)-driven analog precoder optimization for enhanced ISAC performance in sub-THz systems
Zonghui Yang1, Shijian Gao2, Xiang Cheng1
1State Key Laboratory of Photonics and Communications, School of Electronics, Peking University, Beijing 100871, China.
Fundamental Research
|August 1, 2026
Summary
Future sub-terahertz (sub-THz) integrated sensing and communication (ISAC) systems face challenges from beam squint. This study proposes an analog precoder optimization and a lightweight network (CSP-Net) to enhance dual-functional gains.
Area of Science:
- Electrical Engineering
- Wireless Communications
- Signal Processing
Background:
- Integrated Sensing and Communication (ISAC) is crucial for future sub-terahertz (sub-THz) systems.
- Line-of-sight (LoS) propagation dominates sub-THz channels, simplifying transmitter design but introducing challenges.
- The beam squint effect in sub-THz systems hinders the balancing of sensing and communication functionalities in ISAC.
Purpose of the Study:
- To explore the design flexibility of sub-THz analog hardware for ISAC.
- To enhance dual-functional gains by optimizing the analog precoder to adapt to sub-THz channel characteristics.
- To develop a computationally efficient solution for ISAC challenges.
Main Methods:
- Analog precoder optimization to adjust the equivalent channel for enhanced dual-functional gains.
- Development of a lightweight complex-valued squint-aware network (CSP-Net) inspired by the synesthesia of machine (SoM).
- Utilizing both communication and sensing channel data within CSP-Net, with an architecture tailored to specific data and task characteristics.
Main Results:
- Demonstrated that adjusting the equivalent channel through the analog precoder enhances dual-functional gains.
- Proposed a near-optimal benchmark for analog precoder optimization.
- Developed CSP-Net to effectively reduce algorithmic complexity while maintaining performance.
- Validated the effectiveness of the proposed schemes through simulations.
Conclusions:
- Analog precoder optimization is key to overcoming beam squint limitations in sub-THz ISAC.
- The proposed CSP-Net offers an efficient solution for ISAC by leveraging dual-channel data.
- The developed methods significantly enhance ISAC performance in sub-THz environments.
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