Two stage constant-modulus waveform design in ISAC system for CRB minimization

doi:10.23919/JSEE.2025.000154

Abstract

Abstract:

In target tracking stage, the integrated sensing and communication (ISAC) system needs to estimate various target parameters, such as the angle and range, while ensuring highly reliable communication. This paper proposes a two-stage constant-modulus waveform design. In the transmission waveform covariance matrix (TWCM) optimization stage, we minimize the Cramer-Rao bound (CRB) of joint estimation for two-dimensional direction of arrival (DOA) and complex reflection coefficients under total power constraint, obtaining an optimal TWCM. In the alternating optimization based on Riemannian steepest descent (RSD) stage, under constant modulus property and multi-user interference constraints, minimize the squared Euclidean distance between actual TWCM and optimal TWCM obtained from the TWCM optimization stage. To address the optimization problem, an alternate optimization algorithm based on the RSD method is proposed. Simulation results demonstrate that the proposed waveform design simultaneously achieve reliable communication and multi-target tracking.

Key words: integrated sensing and communication, multi-targets tracking, Cramer-Rao bound, waveform design

Xiaohui Li, Mingli Shi, Jing Liu, Xiaobo Wei. Two stage constant-modulus waveform design in ISAC system for CRB minimization[J]. Journal of Systems Engineering and Electronics, 2026, 37(5): 1463-1470.

Figures/Tables 7

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