Background A significant limitation to evaluating three-dimensional, time-dependent wildland fire models is the absence of pre-fire, active-fire and post-fire time-synchronized and quality-assured datasets. Aims The 2014 Camp Swift Fire Experiment integrated data from three controlled burns to create an openly available FAIR (Findable, Accessible, Interoperable, Reusable) dataset for model evaluation. Methods The study collected infrared (IR) and electro-optical (EO) active-fire imagery, field-based wind and fire measurements, pre- and post-fire aerial imagery and vegetation sampling. Rate of spread (ROS), fire depth and flame height were derived, spatially and temporally aligned. We assessed data quality for accuracy, precision and completeness and presented it through GIS products. Key results Despite sensor and synchronization challenges, vegetation classifications and heat flux data showed strong spatial correspondence. IR- and EO-derived ROS values generally agreed with field-based estimates though anemometer data quality varied. Fire behavior observations were linked consistently to vegetation type and wind measurements. Conclusions The Camp Swift dataset represents fully integrated spatiotemporal measurements suitable for evaluating 3D fire models, highlighting the importance of interdisciplinary planning, rigorous quality control and documentation in producing datasets for modeling applications. Implications This work provides a blueprint for future fire experiments and underscores the critical need for quality-assured, integrated datasets to advance operational and research fire modeling capabilities.
Coherent frequency microcombs, generated in nonlinear high-Q microresonators and driven by a single continuous-wave laser, have enabled several scientific breakthroughs in the past decade, thanks to their high intrinsic phase coherence and individual comb line powers. Here, we report terabit-per-second-scale coherent data communications over a free-space atmospheric link, using a platicon frequency microcomb, employing wavelength- and polarization-division multiplexing for next-generation optical wireless networks. Spanning more than 55 optical carriers with 115 GHz channel spacing, we report the first free-space coherent communication link using a frequency microcomb, achieving up to 8.21 Tbit/s aggregate data transmission at a 20 Gbaud symbol rate per carrier over 160 m, even under log-normal turbulent conditions. Utilizing 16-state quadrature amplitude modulation, we demonstrate retrieved constellation maps across the broad microcomb spectrum, achieving bit-error rates below both hard- and soft-decision thresholds for forward-error correction. Next, we examine a wavelength-division multiplexing free-space passive optical network as a baseline for free-space fronthaul, achieving an aggregate data rate of up to 5.21 Tbit/s and a field-tested spectral efficiency of 1.29 bit/s/Hz in the microcomb-based atmospheric link. We also quantify experimental power penalties of ≈ 3.8 dB at the error-correction threshold, relative to the theoretical additive white Gaussian noise limit. Furthermore, we introduce the first-ever demonstration of master–slave free-space carrier phase retrieval with frequency microcombs, and the compensation for turbulence-induced intensity scintillation and pointing error fluctuations, to improve end-to-end symbol error rates. This work provides a foundational platform for broadband vertical heterogeneous connectivity, terrestrial backbone links, and ground-satellite communication.
Phase noise (PN) generated from imperfect oscillators can destroy transmitted data, for instance, by random rotation of the received signal constellation, amplitude variation in multi-antenna systems, or spectrum regrowth. In this work, we develop a decision-directed PN compensation approach using recursive least squares (RLS) with a forgetting factor to compensate for independent local oscillator PN at a multi-antenna receiver in a frequency-selective system. We employ a single reconfigurable intelligent surface (RIS) configured offline and without PN knowledge via the power method. Simulation results show how RIS-only or RIS-aided links can improve PN estimation and detection over a direct link alone at lower signal-to-noise ratio (SNR) settings and motivate future PN estimation improvements in RIS-aided systems.
Semiconductor materials in power electronics are transitioning from silicon to Wide Band-Gap (WBG) semiconductors such as Silicon Carbide (SiC) and Gallium Nitride (GaN) due to their superior performance at higher power levels in automotive and industrial applications. The SiC MOSFET is a promising candidate for next generation power devices since it works at higher voltages, with higher switching speeds and higher thermal conductivity than conventional silicon (Si) devices. The preferred test method to measure the switching parameters of WBG is performed using the Double Pulse Test (DPT) method. Each oscilloscope probe has its own characteristic propagation delay contributing to varying delay in simultaneous acquisition of current and voltage during DPT. It is difficult to remove skew at high dynamic range because of the limitations of present de-skew fixtures. This paper proposes an algorithm to model drain to source voltage using current and to remove WBG waveform skew mathematically post waveform acquisition. This algorithm is demonstrated using WBG-DPT circuit with oscilloscopes analyzing switching loss. Also, the paper demonstrates the modelling of effective power loop inductance at WBG device transitions using drain to source voltage and drain current. The paper includes automation and optimization techniques to model effective power loop inductance in fewer iterations.
In the context of the education of engineers, it has always been a special challenge to convey the balancing act between necessary theory and result-oriented and structured or practically relevant working methods. The field of traffic engineering forms a special role in the context of education. The range of possible disciplines is very wide, which inevitably requires a strong application orientation to convey specialized knowledge in a targeted manner. Traffic telematics is a special discipline with a close connection to electrical engineering and information technology. The subareas cover everything from simple analog sensors to very complex planning and design of smart mobility systems. Nevertheless, it is an essential part of the latter to be able to understand, classify and use individual subcomponents holistically. This paper presents a practice-oriented approach that bridges the gap between theory and practice without losing focus on engineering education using V2X (Vehicle-to-Everything) technology as an example.
