2023/1

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Hydrometeor Classification for Dual Polarization Radar Based on Multi-Sample Fusion SVM
(Společnost pro radioelektronické inženýrství, 2023-04) Luo, Z.; Wang, X.; Wang, L.; Xu, G.; Gao, Y.
In order to enhance the accuracy of dual polarization radar in hydrometeor classification, a hydrometeor classification algorithm based on multi-sample fusion Support Vector Machine (SVM) is proposed in this paper after considering that traditional fuzzy logic algorithm has the defect of over relying on expert experience to set parameters. The data of four polarization parameters (horizontal reflectivity factor, differential reflectivity, correlation coefficient and differential propagation phase constant) detected by the KOHX radar were taken as the feature information of hydrometeors. The dataset was collected, and the model was trained. According to the classification results of SVM model and combined with the distribution characteristics of target particles in the rainfall area, a classification system that can effectively identify four types of particles (dry snow, moderate rain, big drops and hail possibly with rain) was established This model greatly reduced the misidentification of dry snow (DS) and moderate rain (RA)) in the precipitation area, and significantly improved the overall classification effect of hydrometeors in the area. The 0.5-degree elevation scanning data of the radar at a certain time were tested, and the classification accuracy of system model was up to 97.21%. The average accuracy of other elevation scanning data was approximately 97%, which showed strong robustness.
Quasistatic Resonators Based Triple-Mode Notched Microstrip Bandpass Filter
(Společnost pro radioelektronické inženýrství, 2023-04) Hugar, S. I.; Baligar, J. S.; Dakulagi, V.; Vanitha, K. M.
This article discusses new approach for design and development of triple-mode notched microstrip bandpass filter based on quasistatic resonators(QR). The proposed approach is composed of two Quasistatic resonant elements; Horizontal plane Split ring resonator (HP-SRR), Vertical plane split ring resonator (VP-SRR) and a single asymmetric step impedance resonator (A-SIR) with parallel coupled feed structure. An additional attenuation pole realized by VP-SRR in desired passband, tunes the dual-mode response to triple mode and enhances the 3dB bandwidth without changing the dimensions of basic the filter cell. The HP-SRR realizes a notch at WiMAX band (IEEE 802.11a lower band) in the desired passband. Further by changing the impedance of VP-SRR and HP-SRR both the location of additional attenuation pole frequency and notch band can be controlled. The proposed approach results in compact, notched wideband, filter design.
Jointly Optimized Design of Distributed Goppa Codes and Decoding
(Společnost pro radioelektronické inženýrství, 2023-04) Feng, F. A.; Yang, F. F.; Chen, C.; Zhao, C. L.
In order to improve the adverse influence of fading channel in communication system, a distributed Goppa coding scheme is proposed in this paper. Two Goppa codes are set at the source node and the relay node in this scheme respectively. An optimal design criterion at the relay is proposed to obtain the optimal joint resultant code at the destination. Furthermore, two novel joint decoding algorithms are proposed to enhance the overall BER performance of the proposed scheme. Monte Carlo simulations show that the proposed distributed Goppa coding scheme outperforms the non-cooperative scheme. Moreover, the proper information selection approach at the relay performs better than random selection in the proposed distributed Goppa coding scheme.
An Overview of Fully On-Chip Inductors
(Společnost pro radioelektronické inženýrství, 2023-04) Ondica, R.; Kovac, M.; Hudec, A.; Ravasz, R.; Maljar, D.; Stopjakova, V.; Arbet, D.
This paper focuses on full integration of passive devices, especially inductors with emphasis on multi-layer stacked (MLS) structures of fully integrated inductors using patterned ground shield (PGS) and fully integrated capacitor. Comparison of diﬀerent structures is focused on the main electrical parameters of integrated inductors (e.g. inductance L, inductance density LA, quality factor Q, frequency of maximum quality factor F Qmax, self-resonant frequency FSR, and series resistance R DC ) and other non-electrical parameters (e.g. required area, manufacturing process, purpose, etc.) that are equally important during comparison of the structures. Categorization of inductor structures with most signiﬁcant results that was reported in the last years is proposed according to manufacturing process. Final geometrical and electrical properties of the structure in great manner accounts to the fabrication process of integrated passive device. This work oﬀers an overview and state-of-the-art of the integrated inductors as well as manufacturing processes used for their fabrication. Second purpose of this paper is insertion of the proposed structure from our previous work among the other results reported in the last 7 years. With the proposed solution, one can obtain the highest inductance density L A = 23.59 nH/mm 2 and second highest quality factor Q = 10.09 amongst similar solutions reported in standard technologies that is also suitable competition for integrated inductors manufactured in advanced technology nodes.
Design and Synthesis of Parallel-Connected Dielectric Filter Using Chain-Function Polynomial
(Společnost pro radioelektronické inženýrství, 2023-04) Chinda, F. E.; Cheab, S.; Soeung, S.
Design and synthesis of parallel connected die-lectric filters using chained function polynomials are pre-sented in this paper. This filter will offer reduced sensitivity to fabrication tolerance while preserving its return loss response within the desired bandwidth in comparison to traditional Chebyshev filters. A novel transfer function FN according to chained is derived for fourth and sixth-order filters and the synthesis technique is presented. To demon-strate the feasibility of this approach, the circuit simulation based on parallel connected topology is carried out in ADS while the design and simulation of the fourth-order filter in dielectric technology in HFSS. Considerable sensitivity analysis is conducted to prove a better fabrication toler-ance of the filter. In terms of implementation, this design technique will serve as a very useful mathematical tool for any filter design engineer.

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