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Visible light communication (VLC), which provides inherent security and is resistant to RF interference, is a good alternative. This work proposes a VLC system using DC-biased optical (DCO) orthogonal frequency division multiplexing (OFDM) for resilient, high-speed biomedical data transmission through indoor optical fading channel. In this system, data is modulated using quadrature amplitude modulation (QAM) with order 4 and 16. Four equalization methods; block-type, comb-type, superimposed training (ST), and blind channel estimation (CE); are implemented across three patient positioning scenarios. We integrate blind channel estimation and SLM-based PAPR reduction for a dynamic healthcare LiFi scenario. A comprehensive comparative analysis of CE techniques is conducted under realistic patient positioning (LOS\/NLOS) conditions. An analysis of the trade-off between spectral efficiency and energy-to-noise ratio is examined in this context. Simulation results reveal a high Peak-to-Average Power Ratio (PAPR), reaching 15\u00a0dB with block-type CE. To mitigate this, Selected Mapping (SLM) is applied with three complex phase sequences, and three real sequences, achieving up to 4 dB PAPR reduction with no Bit Error Rate (BER) degradation. At 28\u00a0dB SNR, BER values were\n                    <jats:inline-formula>\n                      <jats:tex-math>$$10^{-2}$$<\/jats:tex-math>\n                    <\/jats:inline-formula>\n                    ,\n                    <jats:inline-formula>\n                      <jats:tex-math>$$3\\times 10^{-2}$$<\/jats:tex-math>\n                    <\/jats:inline-formula>\n                    ,\n                    <jats:inline-formula>\n                      <jats:tex-math>$$4\\times 10^{-2}$$<\/jats:tex-math>\n                    <\/jats:inline-formula>\n                    , and\n                    <jats:inline-formula>\n                      <jats:tex-math>$$7\\times 10^{-2}$$<\/jats:tex-math>\n                    <\/jats:inline-formula>\n                    for blind, block-type, comb-type, and ST CE, respectively. Spectral efficiency declines with increased multipath, yet blind CE maintains the highest performance, reaching 0.9\u00a0bits\/s\/Hz with 20 multipath components. Additionally, complex phase vectors in SLM provide an extra 1\u00a0dB PAPR gain over real-valued versions.\n                  <\/jats:p>","DOI":"10.1038\/s41598-026-43583-9","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T16:25:08Z","timestamp":1774887908000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["SLM-based PAPR reduction for improved performance of DCO-OFDM LiFi using blind estimation for healthcare monitoring system"],"prefix":"10.1038","volume":"16","author":[{"given":"Asmaa A.","family":"Sharaf","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hussein","family":"Seleem","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amany","family":"Sarhan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amira S.","family":"Ashour","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,3,30]]},"reference":[{"key":"43583_CR1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1007\/s11107-023-00997-z","volume":"46","author":"RC Fon","year":"2023","unstructured":"Fon, R. 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