The prognostics and health management of Li-ion batteries in electric vehicles are challenging due to the time-varying and nonlinear battery degradation. This paper proposes a model-data-fusion method for battery State of Health estimation and Remaining Useful Life prediction. First, combined with Metabolic Grey Model and Multiple-Output Gaussian Process Regression, a dynamic and data-driven battery degradation model is established to simulate battery complicated degradation behaviors, which takes the capacity degradation as the state variable and takes the internal resistance and polarization resistance from battery Thevenin model as the input variables. Second, to suppress the measurement noises of online battery information, a Particle Filter is utilized to track the battery capacity degradation for State of Health estimation and extrapolate the degradation trajectory for Remaining Useful Life prediction. Furthermore, battery ageing experiments are conducted to verify the proposed model-data-fusion method. The verification results show that the proposed method can provide an accurate and robustness State of Health estimation and Remaining Useful Life prediction at different temperatures.

In this work, a polarization conversion metasurface is proposed, which can convert linearly polarized electromagnetic (EM) waves into cross-polarized waves in ultra-wideband at high polarization conversion efficiency. The proposed sandwiched metasurface, composed of a top anisotropic resonator structure, an intermediate dielectric substrate, and a bottom metallic ground, has an extremely thin thickness (only 6.6% of the longest wavelength of the working frequency range). Both numerical simulation and experimental results illustrate that the metasurface can work in the ultra-wideband (ranging from 9.04 to 20.83 GHz) with a high polarization conversion ratio (>0.9). Polarization conversion in a wide bandwidth is attributed to multiple resonances in the operating frequency range. Additionally, the proposed metasurface also shows good performance for oblique incidence. It is expected that the designed metasurface will be more convenient for integration within ultra-thin EM devices.

The rapid development of wireless technology has heightened the requirement for antenna performance. Traditional antennas, characterized by their static performance, are no longer sufficient to accommodate the dynamic requirements of modern wireless systems. The advent of reconfigurable antennas has opened new horizons for unleashing the full potential of wireless communication systems. These antennas are versatile and can switch various performance modes in a simple yet ingenious structure. Based on the cutting‐edge research, this paper deeply explores their core design principles, the latest breakthroughs, and the ingenious methods. Through an in‐depth analysis of a multitude of reconfigurable antenna design cases, existing design methods are categorized into four categories: electronic and optical switches, structural physical change, smart materials, and bistable composites. Each category is subjected to a meticulous dissection, revealing the underlying design mechanisms, highlighting innovativeness, and discussing both the strengths and limitations. Furthermore, by conducting a comprehensive comparative analysis, this paper concludes the forthcoming challenges and prospective trajectories for this research domain. Therefore, this paper can serve as a valuable reference for researchers seeking to deepen their understanding and application of various reconfiguration methods in the design of reconfigurable antennas, guiding them toward the forefront of antenna technology innovation.