Fully 3GPP-Compatible Long-Range Sensing for LEO-ISAC: A Window-Grid Processing Framework

2026-09-24

AI Summary

This study addresses the OFDM sensing symbol misalignment and signal duration mismatch caused by long propagation delays in low Earth orbit integrated sensing and communication (LEO-ISAC) systems. To overcome these challenges, this work proposes a receiver-side windowed grid processing framework. By exploiting the geometric determinism of targets, the method performs purely receive-side signal processing, ensuring full compatibility with 3GPP standards without requiring any modifications to the transmitted waveform. Experimental results demonstrate that the proposed scheme achieves meter-level ranging accuracy at bistatic distances exceeding 640 kilometers. These findings indicate that the framework provides an efficient and practical solution for standardized long-range bistatic radar sensing within LEO-ISAC networks.

Abstract

This paper addresses the long-range sensing problem in bistatic low-Earth-orbit integrated sensing and communication (LEO-ISAC) systems. Conventional OFDM-based sensing schemes fail in LEO-ISAC due to excessive propagation delays, which cause cross-symbol misalignment and unequal signal durations. We propose a window-grid processing framework that leverages the deterministic target geometry to resolve both challenges as a pure receiver-side processing: the transmitted sensing signal is 3GPP-compatible. Simulations demonstrate meter-level ranging accuracy for two targets at bistatic ranges beyond 640 km with 100.8 MHz bandwidth.

Problem

• LEO-ISAC
• long-range sensing
• bistatic sensing
• propagation delay
• OFDM

Innovation

• LEO-ISAC
• Window-Grid Processing
• 3GPP-Compatible
• Long-Range Sensing
• OFDM