{"title":"The Fusion Method of Sea Clutter Amplitude Distribution Model*","authors":"Zhe-dong Zhang, Yunchao Yu, Jinpeng Zhang, Yushi Zhang, Xin Li, Hao Ding","doi":"10.1109/ISAPE.2018.8634257","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634257","url":null,"abstract":"In the situation of high resolutions, high sea states and small grazing angles, the sea clutter amplitude distribution has heavy trailing part, this part has a significant impact on the sea surface target detection. This paper introduces a fusion method of sea clutter amplitude distribution model, based on which new amplitude distribution models of sea clutter can be designed, and thus the trailing part of the sea clutter amplitude distribution can be well fitted. Through the verification by using the sea clutter data of UHF, L, and S-band, it is indicated that the introduced fusion method can give a better fit in the trailing part of the sea clutter amplitude distribution than other conventional modeling methods. Further, for the amplitude distribution without heavy trailing part, this method also has a good fitness.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114308776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Reducing Mutual Coupling of Millimeter Wave Array Antennas by Fractal Defected Ground Structure","authors":"Jingxia Qiang, F. Xu, Wenjun Fan","doi":"10.1109/ISAPE.2018.8634210","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634210","url":null,"abstract":"A high isolation, high gain and compact patch antenna arrays that operates in 11.4–11.78 GHz by using fractal defected ground structure (Fractal-DGS) is designed. Performance of the antenna arrays, such as isolation and radiation, are simulated and compared with conventional patch antenna array without Fractal-DGS. As is presented in this paper, the mutual coupling is −33dB at working frequency, it reduces 13dB compared with the traditional antenna array. And the radiation direction is better than conventional antennas too. Higher isolation and stable directional radiation pattern make this antenna array a better choice for millimeter wave communication system.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123228069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Broadband High Efficiency Class-J Power Amplifier with a Novel Output Matching Method","authors":"Zhiwei Zhang, Guohua Liu, Hao Sun, Zhi-qun Cheng","doi":"10.1109/ISAPE.2018.8634146","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634146","url":null,"abstract":"This paper presents a new method to design broadband high efficiency Class-J power amplifiers (JPAs). The wideband output matching network (OMN) is designed with a new simplified output impedance calculation method by using a two-port network. For demonstration, a broadband high efficient Class-J power amplifier based on proposed method is implemented using Cree 10-W packaged GaN HEMT devices. Measurement results show that 64%-68% drain efficiency is achieved and between 40-41.6 dBm output power with more than 10 dB gain over the frequency band of 1.2-2.6 GHz, the proposed amplifier has an ACPR between - 27.5 and −32.4 dBc over the entire band.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122016443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Novel Method for PD Measurement Using the Equipment Shell Slot as Sensing Antenna","authors":"Chong Sun, Hongfu Guo, W. Hao","doi":"10.1109/ISAPE.2018.8634098","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634098","url":null,"abstract":"Most of the existing high-voltage electrical equipment in operation uses external or internal Ultra High Frequency (UHF) detection sensors when detecting partial discharge (PD) signals, which brings difficulties to the already operating equipment. Based on the basic theory of slot antenna and the equipment shell itself, a novel method for PD detection is proposed in this paper: use the existing slots of the equipment shell as sensing antenna for PD measurement. In this paper, simulation models are built by the electromagnetic simulation software Ansoft HFSS to study the characteristics of shell slots as sensing antennas. The Laboratory simulations are also conducted. The research shows that the shell slot can be used as an antenna to receive the electromagnetic wave of PD inside the equipment and receive PD signals of different frequency ranges based on different sizes of the shell slot, which greatly reduces the difficulty of on-line PD detection. The conclusion of this study subverts the conventional design of UHF PD sensor and provides an important guiding direction and theoretical basis for improving the sensor design of UHF detection system.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122669036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guo-peng Yang, Jin-ping Zhang, Yi Yang, Zhipeng Zhou
{"title":"A Ka-Band Wideband SIW Cavity-Backed Slot Antenna Array","authors":"Guo-peng Yang, Jin-ping Zhang, Yi Yang, Zhipeng Zhou","doi":"10.1109/ISAPE.2018.8634154","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634154","url":null,"abstract":"A wide band substrate integrated waveguide (SIW) cavity-backed antenna operating in Ka band is presented in this paper. The proposed SIW cavity is octagonal with two trapezoidal slots on it. Additional substrate is added upon the cavity as an impedance transformer. Then a $2times 2$ antenna array is designed to further increase the antenna gain. Simulated results demonstrate that the $vert mathbf{S}_{11}vert < -10 mathbf{dB}$ impedance bandwidth of the proposed antenna reaches 30.2% (23.0-31.2 GHz), and the antenna array achieves 20.2% (24.5-30.0 GHz) impedance bandwidth and stable gain throughout the operating bandwidth with a peak of 13.8 dBi.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122745966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hidden Markov Model Based on Target Narrow Pulse Laser Transient Characteristics","authors":"Yali Hou, Hong Su, Bo Tian, Tie Li","doi":"10.1109/ISAPE.2018.8634126","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634126","url":null,"abstract":"Aiming at the fact that the narrow pulse laser transient characteristics of target have not been applied in target recognition, a hidden Markov model (HMM)based on transient characteristics is proposed. For the scattering characteristics of each target in different poses, the reliable model parameters of each target were completed by using the training samples, and each hidden Markov model was established. The maximum likelihood of the test samples for each model was calculated, the target feature class corresponding to the largest probability value was selected as the output category. The result shows that target recognition by hidden Markov model has better performance in terms of calculation speed and accuracy. This method is fast and effective.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123871272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A new TMA method for state estimation of underwater target","authors":"Wei Sun, Pulong Nan","doi":"10.1109/ISAPE.2018.8634384","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634384","url":null,"abstract":"In this paper, a novel target motion analysis (TMA) method using unscented Kalman Filter (UKF) based on modified polar coordinates (MPC) is proposed to improve the localization accuracy for underwater target with constant velocity. The proposed approach utilizes bearings of two-arrays to estimate the localization and velocity of the target. Unlike extended Kalman filter, unscented Kalman Filter (UKF), which is biased and sensitive to the initial value in Cartesian coordinate, the proposed scheme is much more stable and asymptotically unbiased. Moreover, the performances among these schemes are compared based on the noisy bearings from towed array sonar and flank array sonar via Monte Carlo simulations. Simulation results show that the proposed MPC-UKF has better performances with higher numerical stability and little cost of computational complexity.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123987478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A 2D Numerical Study of the Langmuir Parametric Instability in the Ionospheric Modification","authors":"T. Feng, Moran Liu, Chen Zhou","doi":"10.1109/ISAPE.2018.8634388","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634388","url":null,"abstract":"Parametric Decay Instability (PDI) plays an important role in the interaction of the high-power HF EM waves with ionosphere plasma. In this study, we have constructed a 2D numerical simulation model for studying PDI with a nearly realistic ionosphere background and a radio wave propagation model by taking a proper processing for the routine dynamic equations of plasma with generalized Zakharov method. The simulation results found that high-power HF EM waves could excite two electrostatic modes of a Langmuir wave and an ion acoustic wave near the reflection point of the ordinary wave (O-mode) within a timescale order of millisecond. The amplitude of density perturbation grows exponentially and significantly influencing the plasma frequency related to ‘low frequency’ density background. These processes are also followed by plasma caviton structures and trapped Langmuir waves. Finally, the O-mode heating leads to an intense localized turbulence. This paper also presents the simulation results of Langmuir parametric instability (LPI) excited by powerful HF wave heating at the O-mode reflection height. The study of this article contributes to formation of a deep impression for the physical mechanism of the Parametric Decay Instability (PDI). It is also helpful to research on the nonlinear interaction between the high-power HF EM waves and ionosphere plasma.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124217197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Meridional Direction Features of Equatorial and Low-Latitude Plasma Depletions Observed by Swarm Satellites","authors":"Shihan Zhang, Yuhua Zou","doi":"10.1109/ISAPE.2018.8634039","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634039","url":null,"abstract":"The equatorial and low-latitude plasma depletions is an important space weather phenomenon, which often produce severe ionospheric scintillations. According to the well-known formation mechanism of the equatorial and low-latitude plasma depletions, i.e., the generalized Rayleigh-Taylor (RT) instability mechanism, these plasma depletions are expected to occur mainly at night and appear simultaneously at the geomagnetic conjugate locations in the northern and southern hemisphere. Although many studies on the equatorial and low-latitude plasma depletions have been performed in recent years, there are few reports on the variation features of the equatorial and low-latitude plasma depletions along the geomagnetic meridian direction. In this study, we have analyzed in situ electron density measurements obtained by the three Swarm satellites in the 55°E-155°E geographic longitude (GLON) sector during the equinox months of high solar activity years, i.e., February-April 2014, September-November 2014, February-April 2015, and September-November 2015. We found that the equatorial and low-latitude plasma depletions were observed mainly at night, which are consistent with the statements of the generalized RT instability mechanism. Moreover, we found that in most cases the appearance of the equatorial and low-latitude plasma depletions presented the north-south hemisphere symmetry. However, sometimes (with the occurrence rate of ∼16-27%) they presented the north-south hemisphere asymmetry, namely, they were only detected at the low-latitude region in the northern hemisphere or southern hemisphere, which cannot be explained by the generalized RT instability mechanism.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125323464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Rauf, Hailong Li, Safi Ullah, L. Meng, Bin Wang, Maoyan Wang
{"title":"Role of high energy precipitating particles on PMSE echoes during the simultaneous observations carried out by EISCAT VHF and UHF radar","authors":"A. Rauf, Hailong Li, Safi Ullah, L. Meng, Bin Wang, Maoyan Wang","doi":"10.1109/ISAPE.2018.8634250","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634250","url":null,"abstract":"We investigate the role of precipitating energetic particles in producing PMSE echoes during the simultaneous observations conducted simultaneously by both the EISCAT VHF and UHF radars on 8 and 9 Aug 2015. Since PMSE echoes are observed even in the absence of particle precipitation in case of EISCAT VHF observations, precipitating energetic particles might be one possible reason but are not necessary for producing PMSE echoes. However, the absence of PMSE echoes during the precipitating particle precipitation in case of observations carried out simultaneously by EISCAT UHF radar shows that particle precipitation might play an important role in PMSE creation at lower frequencies.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125375445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}