Transmission Mask Analysis for Range-Doppler Sensing in Half-Duplex ISAC

2026-01-15

AI Summary

This work addresses the sidelobe interference and mainlobe stability issues in half-duplex ISAC systems under periodic transmission masks in the range–Doppler sensing domain. By constructing periodic masks via cyclic difference sets (CDS), and leveraging autocorrelation analysis together with closed-form expected response derivations, the study reveals for the first time the sparsity of Doppler sidelobes and their intrinsic trade-off with mainlobe fluctuations. The notion of range sidelobe optimality is extended to the two-dimensional range–Doppler domain, establishing an optimization theory for CDS-based masks across varying dynamic scenarios. Specifically, it is proven that Singer CDS achieves minimax optimality under moderate dynamics, while under high dynamics, the Doppler sidelobe energy becomes a concave function of the mask autocorrelation, thereby quantifying the fundamental trade-off between sidelobe suppression and mainlobe stability.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Search and Optimization: Mixed Discrete/Continuous Search
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization

Application Category

• Security and Privacy: Large-scale security measurements
• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Responsible Web: Measurement, analysis, and circumvention of Web censorship

Abstract

In this paper, we analyze the periodic transmission masks for MASked Modulation (MASM) in half-duplex integrated sensing and communication (ISAC), and derive their closed-form expected range-Doppler response $\mathbb{E}\{r(k,l,\nu)\}$. We show that range sidelobes ($k\neq l$) are Doppler-invariant, extending the range-sidelobe optimality to the 2-D setting. For the range mainlobe ($k=l$), periodic masking yields sparse Doppler sidelobes: Cyclic difference sets (CDSs) (in particular Singer CDSs) are minimax-optimal in a moderately dynamic regime, while in a highly dynamic regime the Doppler-sidelobe energy is a concave function of the mask autocorrelation, revealing an inevitable tradeoff with mainlobe fluctuation.

Problem

• Integrated Sensing and Communication
• Range-Doppler sensing
• Transmission mask
• Sidelobe optimization
• Half-duplex

Innovation

• periodic transmission masks
• range-Doppler response
• cyclic difference sets
• Doppler-invariant sidelobes
• mask autocorrelation