Work

Joint Beamforming Design for UAV‐Enabled ISAC Systems: A Riemannian Trust‐Region Approach

Year: 2026
Type: article
Abstract: ABSTRACT This paper investigates the joint beamforming design for ISAC‐enabled UAV systems, aiming to optimise the trade‐off between communication sum rate (SR) and sensing Cramér–Rao lower bound (CRLB) under stringent size, weight and power (SWaP) constraints. Departing from traditional relaxation methods, we first address the nonconvexity and variable coupling by constructing a tractable quadratic surrogate objective, which transforms the intractable original objective into an unconstrained optimisation framework strictly defined on the complex sphere manifold (CSM). We then propose a Riemannian trust‐region algorithm on the complex sphere manifold (RTR‐CSM). The problem is reformulated as a tractable quadratic surrogate, with a finite‐difference approximated Hessian used to construct the trust‐region subproblem, which is solved via truncated conjugate gradient to avoid expensive exact second‐order derivations and matrix inversions. Simulations show that RTR‐CSM achieves near‐optimal performance and converges significantly faster than state‐of‐the‐art benchmarks in terms of iteration count (e.g., reducing total runtime by 5.2×, 3.9×, and 2.9× compared with SCA, FP‐SGDA, and IRO‐CSM, respectively), making it highly suitable for resource‐constrained UAV‐enabled ISAC beamforming.
Language: English
Open Access status: gold
Estimated APC paid: $2,620
OpenAlex ID: W7208826713
FWCI:
Cites: 20
Cited by:
Related to: 10