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2026-02-09 Latest Published

Photovoltaic Power Prediction Model Based on Fuzzy Entropy Clustering and Self-Attention Mechanism Combined with ICEEMDAN-WOA-CNN-BiLSTM
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By Zhongan Yu Faneng Wu Zhiwei Huang Zihao Deng Feng Zhang

Progress In Electromagnetics Research C, Vol. 166, 27-40, 2026

doi:10.2528/PIERC25122407 | Google Scholar

Abstract

To address the randomness and nonlinearity of photovoltaic (PV) power caused by meteorological factors, this paper proposes an ICEEMDAN-WOA-CNN-BiLSTM prediction model integrated with fuzzy entropy clustering and a self-attention mechanism. First, the original PV power sequence is decomposed into multiple multi-scale intrinsic mode function (IMF) components and residuals via the Improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (ICEEMDAN). Subsequently, components with similar complexity are merged using fuzzy entropy clustering to simplify the calculations. Then, the Whale Optimization Algorithm (WOA) is adopted to optimize the hyperparameters of the CNN-BiLSTM model, and the self-attention mechanism is integrated into the model to enhance the weights of key features. Comparative experiments demonstrate that the proposed model significantly outperforms single and traditional hybrid models in terms of Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Coefficient of Determination (R2). This can effectively improve the accuracy of short-term PV power prediction and provide support for power station dispatching and power grid stability.

2026-02-09

PIER C

Vol. 166, 27-40, 2026

doi:10.2528/PIERC25122407

download: 81

Photovoltaic Power Prediction Model Based on Fuzzy Entropy Clustering and Self-Attention Mechanism Combined with ICEEMDAN-WOA-CNN-BiLSTM

Zhongan Yu, Faneng Wu, Zhiwei Huang, Zihao Deng and Feng Zhang

2026-02-09

PIER C

Vol. 166, 19-26, 2026

doi:10.2528/PIERC25121605

download: 18

A Miniaturized Highly Isolated Quad-Port Penta-Band-Notched UWB MIMO Antenna Based on EBG Structures

Koritala Nagavardhani, Pullagura Rajesh Kumar and Veera Malleswara Rao

This paper presents a miniaturized quad-port ultrawideband (UWB) MIMO antenna that integrates band-notch functionality and exhibits high isolation. The design employed four circular monopole radiators positioned on a modified defected ground structure (DGS), and periodic electromagnetic bandgap (EBG). These EBG components are an advanced variation of traditional mushroom-type structures that incorporate grid-shaped top patches, a metallic ground plane, and multiple vias connecting both layers. Located at the center of the substrate, the EBG network effectively reduces the electromagnetic coupling between adjacent radiating elements. To achieve multi-band rejection, five inverted U-shaped slots are etched into each monopole, enabling selective suppression of unwanted frequencies at 3.36-3.56 GHz, 3.72-3.92 GHz, 4.11-4.32 GHz, 4.59-4.83 GHz, and 5.22-5.50 GHz, corresponding to WiMAX, C-band, Wi-Fi, INSAT, and WLAN systems. Experimental validation confirms that the antenna attains -10 dB impedance bandwidth extending from 3.0 to 14.0 GHz, with inter-element isolation above -22.5 dB, gain of 6.2 dB, and radiation efficiency reaching 79.2%.

A Miniaturized Highly Isolated Quad-Port Penta-Band-Notched UWB MIMO Antenna Based on EBG Structures

2026-02-09

PIER C

Vol. 166, 9-18, 2026

doi:10.2528/PIERC25122502

download: 18

Broadband Array Aperture Fill Time Correction Algorithm Based on Low-Complexity Variable Fractional Delay Filter

Yufan Wang, Mingwei Shen, Zixuan Wang and Guodong Han

To address the aperture fill time problem in broadband arrays, this paper proposes an efficient delay compensation algorithm based on a variable fractional delay (VFD) filter with high numerical stability. A low-complexity Newton structure is introduced into the VFD Lagrange interpolation algorithm; in addition, the numerical stability is significantly enhanced by centrally offsetting the element delay parameters and avoiding the explicit inversion of the transformation matrix. Subsequently, the robust Newton-VFD is applied to the implementation of the broadband array aperture fill time correction algorithm. The algorithm utilizes a cascaded architecture consisting of coarse integer-delay compensation and fine fractional-delay correction via the Newton-VFD. Simulation results demonstrate that the proposed low-complexity Newton-VFD significantly reduces hardware complexity while maintaining excellent magnitude-frequency characteristics, which enables efficient and high-precision correction of broadband array aperture fill time.

Broadband Array Aperture Fill Time Correction Algorithm Based on Low-Complexity Variable Fractional Delay Filter

2026-02-09

PIER C

Vol. 166, 1-8, 2026

doi:10.2528/PIERC25122409

download: 27

A Design Approach of High-Efficiency Filtering Power Amplifiers Using Harmonic-Tuned Network and Terminated Coupled-Line Structures

Lang Ran, Bin Wang, Yongxin Wang and Shihao Chen

A design approach using a harmonic-tuned network (HTN) and terminated coupled-line structures (TCLSs) for high-efficiency filtering power amplifiers (FPA) is proposed in this paper, effectively addressing the efficiency degradation caused by the integration of filtering structures in conventional FPA designs. The proposed approach enables compact circuitry while providing bandpass filtering characteristics. Bandpass filtering is realized through the cascaded TCLSs, while the incorporation of open-circuit and short-circuit branches introduces additional transmission zeros and poles, significantly improving frequency selectivity. In addition, HTN enables precise control of the harmonic impedance, effectively improving the efficiency of the power amplifier (PA). Based on this approach, an FPA operating in the 2.3-2.6 GHz band is designed and implemented. Experimental results show that the FPA achieves a output power (Pout) of 40.8-41.3 dBm, a drain efficiency (DE) of 67.2-72.2%, a gain of 12.8-13.3 dB, and stopband suppression greater than 39 dB on both sides of the passband. These results verify the effectiveness of the proposed design in enhancing PA efficiency and enabling circuit miniaturization, while also providing a feasible design approach for FPA development.