WOS2 – Wireless, Optical and Satellite Networks
Wednesday, 3 June 2026, 17:00-18:30, room Sala 5 (1st floor)
Session Chair: Alessandro Vanelli-Coralli (University of Bologna, IT)
Analytical Derivation of OOK Error Probability Under Signal-Dependent ISI and Background Noise in NLOS Optical Wireless Links
Andrea Petroni (Fondazione Ugo Bordoni, Italy); Mauro Biagi (Sapienza University of Rome, Italy)
On-Off Keying is one of the most widely adopted intensity-modulation formats in optical wireless communication thanks to its simplicity, energy efficiency, and ease of implementation with low cost light sources and detectors. This paper investigates the impact of highly reflective coatings on the performance of On-Off Keying in non-line-of-sight optical wireless links. While most of existing studies assume additive white Gaussian noise and line-of-sight propagation, we consider more realistic coated environments where multipath reflections extend the channel impulse response, thus producing asymmetric intersymbol interference that depends on the transmitted bit pattern. In addition, we provide a detailed analysis of receiver noise, including both a signal-dependent component due to photon shot noise, and an additive background term arising from ambient illumination. A complete analytical model is derived to evaluate the error probability under these conditions. Monte Carlo simulations confirm the accuracy of the proposed theoretical formulation. Moreover, results highlight that neglecting the considered propagation effects leads to optimistic error probability estimates, especially in coatings configurations with reflectance above 0.7, where intersymbol interference spreads over several symbol intervals.
Blind 5G NR LEO Initial Access Receiver
Chen Jaminon-De Roeck (IMDEA Networks, Spain); Timothy Otim (IMDEA Networks Institute, Spain); Giuseppe Santaromita and Domenico Giustiniano (IMDEA Networks, Spain)
LEO satellite links pose severe challenges for 5G NTN initial access due to large carrier frequency offsets, rapidly varying Doppler, and low SNR, conditions that make fully blind operation necessary in cold-start scenarios. We motivate our study with a real 5G NTN LEO over-the-air testbed emulation that shows that Doppler compensation accuracy directly governs UE connection outcomes, with residual errors needing to be constrained to within a few kilohertz (less than 3 KHz) to enable reliable synchronization and attachment. We then present a fully blind, feedforward receiver that attaches physically motivated confidence measures to each processing stage and uses those confidences to gate hypothesis selection, weighting, and final lock decisions. The design includes a conservative, reliability-aware multi-SSB PBCH soft-combining stage that only supplements, but does not replace, single-SSB channel quality assessment. Deterministic results from 3GPP-compliant simulations demonstrate robust blind synchronization under ±100 kHz offsets and successful PBCH decoding at challenging low SNRs in urban NLOS conditions.
Square vs. Hexagonal OWC Performance
Ali Mahbas (Brunel University London, United Kingdom (Great Britain)); John Cosmas (Brunel University, United Kingdom (Great Britain))
Accurate performance evaluation is essential for unlocking the full potential of Optical Wireless Communication (OWC) systems, particularly in the presence of different network deployment strategies. This paper presents a comprehensive analytical framework for evaluating OWC system performance that explicitly accounts for key system parameters, including inter-node distance, height difference, and full cell geometry, thereby overcoming limitations introduced by simplifying assumptions commonly adopted in the literature. Using the proposed framework, a systematic and balanced comparison between the two most widely used network configurations, namely hexagonal and square deployments, is conducted. Two deployment scenarios are considered. In the first scenario, both deployments employ the same inter-node distance. In the second scenario, the inter-node distance in the square deployment is reduced to account for differences in node density and enable a fair comparison. Simulation results validate the accuracy of the proposed analytical model and demonstrate that disc-shaped cell approximations can lead to misleading performance predictions. The results further show that, when identical inter-node distances are used, the square deployment generally achieves higher coverage probability across most signal-to-interference-plus-noise ratio (SINR) thresholds. When node density is equalized, the hexagonal deployment offers comparable performance at low and medium SINR thresholds for larger inter-node distances, while the square deployment consistently provides higher coverage probability at high SINR thresholds. These findings provide practical insights into the impact of network geometry on OWC system design.
E-ConPA: An Enhanced Contention-Free Mechanism with Power Adaptation for Future Wi-Fi
Meizhen Zhuo (Nokia Bell Labs, Germany); Francesc Wilhelmi (Universitat Pompeu Fabra, Spain); Stephan ten Brink (University of Stuttgart, Germany); Silvio Mandelli (Nokia Bell Labs, Germany)
Distributed Listen-Before-Talk (LBT)-based mechanisms in Wi-Fi struggle to address the ever-increasing demand for ultra-dense wireless connectivity. This paper introduces Enhanced Contention-free with Power Adaptation (E-ConPA), a mechanism that breaks with traditional LBT methods by removing contention and allowing devices to access the channel promptly. This property is key to reducing the overall network delay, which is necessary in the next generation of Wi-Fi. E-ConPA fosters high performance and reliability in very dense Wi-Fi deployments through a power adaptation strategy that includes Received Signal Strength Indicator (RSSI) measurements from the neighboring Access Points (APs). Our results empirically highlight the significant performance and efficiency gains that E-ConPA achieves compared to state-of-the-art mechanisms, which are up to 88% in terms of throughput, and up to 90% in terms of Area Spectral Efficiency (ASE). Furthermore, E-ConPA effectively addresses the issue of degraded performance experienced by the cell edge Stations (STAs) of prior works proposing similar paradigms.
Time-Adaptive VLC Channel Estimation Under Random User Mobility
Maysa Yaseen and Salama Said Ikki (Lakehead University, Canada)
Indoor visible light communication (VLC) systems operating in dynamic environments experience channel fluctuations due to user mobility. These fluctuations, combined with signal-dependent and thermal noise, pose major challenges to maintaining reliable high-speed links. This paper investigates a practical indoor VLC scenario in which the user’s position varies over time. A new modeling framework is proposed for a single-input single-output (SISO) VLC system that exploits the correlation between the received signal and the prior information. Channel estimation is examined under signal-dependent noise, and the dynamic Cramér-Rao lower bound (DCRLB) is derived. The bound is then employed to assess the mean-squared error (MSE) performance of the simple least squares (LS) estimators, as well as the extended Kalman filter (EKF).
