Sparse Solution Trade-offs in GMP DPD: A Least Squares Thresholding Approach

Ellison Murray

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arXiv · 2606.14907

Sparse Solution Trade-offs in GMP DPD: A Least Squares Thresholding Approach

Ellison Murray

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Abstract

Power amplifiers (PAs) in satellite communication systems introduce nonlinear distortion, degrading spectral fidelity. Digital pre-distortion linearizes the PA response, but full-complexity solutions are prohibitive under strict size, weight, and power (SWaP) constraints. We propose the use of Least Squares Thresholding (LST) and compare it against Orthogonal Matching Pursuit (OMP) and Matching Pursuit. LST achieves a 2.77x complexity reduction while maintaining near-identical linearization performance to OMP.

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Ellison Murray. 2026-06-12. Sparse Solution Trade-offs in GMP DPD: A Least Squares Thresholding Approach. https://arxiv.org/abs/2606.14907

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