{"ID":6138910,"CreatedAt":"2026-07-09T01:07:32.349475501Z","UpdatedAt":"2026-07-10T23:21:00.654494504Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2607.06861","arxiv_id":"2607.06861","title":"Performance Limits of FRIS Systems in Nakagami-$m$ Fading","abstract":"Fluid reconfigurable intelligent surfaces (FRIS) have recently emerged as a promising technology for enhancing wireless link reliability through spatial decorrelation. However, their performance analysis remains challenging due to the sum-product structure of the cascaded channel. This letter develops a rigorous analytical framework for FRIS-assisted wireless systems over arbitrarily correlated Nakagami-$m$ fading channels. Specifically, we introduce a physically consistent correlation model for Nakagami-$m$ fading and derive tractable statistical characterizations for the cascaded channel. These results lead to rigorous lower bounds for the outage probability (OP), with a simplified expression also obtained for the independent and identically distributed case. To the best of our knowledge, these are the first strict OP lower bounds reported for an FRIS-aided wireless system under arbitrarily correlated Nakagami-$m$ fading. CLT- and Gamma-based approximations are included as benchmark methods. Notably, the numerical results show that the proposed OP bound not only provides rigorous performance guarantees but also yields a noticeably tighter OP characterization than the CLT approximation in the high-SNR regime.","short_abstract":"Fluid reconfigurable intelligent surfaces (FRIS) have recently emerged as a promising technology for enhancing wireless link reliability through spatial decorrelation. However, their performance analysis remains challenging due to the sum-product structure of the cascaded channel. This letter develops a rigorous analyt...","url_abs":"https://arxiv.org/abs/2607.06861","url_pdf":"https://arxiv.org/pdf/2607.06861v1","authors":"[\"Masoud Khazaee\",\"Felipe A. P. de Figueiredo\",\"Rausley A. A. de Souza\",\"Farshad Rostami Ghadi\",\"Kai-Kit Wong\",\"Luciano L. Mendes\",\"Fernando D. Almeida García\"]","published":"2026-07-07T23:24:57Z","proceeding":"eess.SP","tasks":"[\"eess.SP\"]","methods":"[]","has_code":false}