{
  "abstract": "A receiver can change its observation state while the physical signal remains the same. In rate-splitting multiple access (RSMA) downlinks, this distinction separates receive-beam design and phase-reference transport from the motion of the satellite--UAV line of sight. We formulate receive optimization within the physical--observation dual-axis (PODA) structure and obtain three complementary results. For a known line-of-sight response and positive-definite receiver-noise covariance, a noise-weighted matched combiner simultaneously maximizes every decoding SINR and the minimum user rate. Under directional uncertainty, the principal eigenvector of the conditional response covariance globally maximizes mean array gain; for a Gaussian directional model, an equal-amplitude receiver is optimized by steering towards the conditional mean. Mean rate requires a different objective. We prove that the RSMA common-rate water level is jointly concave in the users' receive gains and derive a semidefinite relaxation with a computable global upper bound. A feasible rank-one beam can therefore be compared directly with the optimum of the finite-scenario problem. We also derive a precision-weighted linear predictor that suppresses uncertain physical-velocity estimates after observation-frame transport. Paired dynamic simulations reduce direction-cosine RMSE by 51.29\\% relative to unrestricted nine-point extrapolation. In a separate uncertainty experiment, direct rate optimization increases mean minimum spectral efficiency from 0.32425 to 0.41712 bit/s/Hz, an improvement of 28.64\\%; the corresponding design objective is within $2.28\\times10^{-4}$ bit/s/Hz of a global upper bound. The phase-transport equation fixes a coherent representative of each optimal beam without changing its gain.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.14641",
  "author_total": 1,
  "authors": [
    {
      "name": "Xianwei Meng"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1s7wxsay1r0cz.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.14641",
  "fulltext_url": null,
  "id": "1s7wxsay1r0cz",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.14641",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cs.IT"
    ],
    [
      "arxiv",
      "math.IT"
    ],
    [
      "openalex",
      "2202|Satellite Communication Systems"
    ]
  ],
  "openalex": "W7221826629",
  "pdf_url": "https://arxiv.org/pdf/2610.14641",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-10",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1s7wxsay1r0cz.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:15Z",
      "native_id": "2610.14641",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.14641"
    }
  ],
  "subjects": [
    {
      "field": "mathematics",
      "origin": "arxiv:math.IT",
      "subfield": "general"
    }
  ],
  "title": "Optimal Receive Design on the Observation Axis for RSMA Satellite-UAV Downlinks",
  "title_text": "Optimal Receive Design on the Observation Axis for RSMA Satellite-UAV Downlinks",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:15Z",
  "url": "https://research.draconitic.com/paper/1s7wxsay1r0cz",
  "venue": "arXiv",
  "versions": []
}