{"title":"Wideband bow-tie slot antenna with tuning stubs","authors":"A. Eldek, A. Elsherbeni, C.E. Smith","doi":"10.1109/NRC.2004.1316493","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316493","url":null,"abstract":"Printed bow-tie and bow-tie slot antennas are planar-type variations of the biconical antenna that has wideband characteristics. We present the effects of adding a tapered metal stub to a bow-tie slot antenna design to enhance the antenna bandwidth for X-band operation. Our study yields a design with 88% bandwidth relative to 10 GHz. The simulation and analysis are performed using the commercial computer software package, Momentum of Agilent Technologies, Advanced Design System (ADS). Verification of the ADS results is performed by using our developed finite difference time domain (FDTD) code and with measurements of the return loss from 7 to 15 GHz.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133831638","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":"Comparison of the radar clutter cancellation performance of post- and pre-Doppler STAP for ground moving target identification from an experimental airborne surveillance radar","authors":"P. G. Kealey, I.P. Finley","doi":"10.1109/NRC.2004.1316472","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316472","url":null,"abstract":"Within this paper we report our study that compared the performance of pre-Doppler and post-Doppler STAP processing algorithms applied to the same radar trials data, collected by QinetiQ's Enhanced Surveillance Radar. The performance of these algorithms was quantified by clutter cancellation ratios and target signal improvement factors (the ratio of the signal to clutter plus noise ratios with and without STAP processing). We have shown that pre-Doppler and post-Doppler STAP may be tuned to give the same level of clutter cancellation. We present results in which bright target signatures are seen to affect the STAP processors and reduce the overall clutter cancellation. We have found that for our two phase center trials radar data, PRI staggered post-Doppler STAP gives greatly enhanced clutter cancellation compared to the simple fixed window post-Doppler STAP. The application of either moving window or auxiliary bin post-Doppler STAP was found to degrade the processor output. The importance of normalizing the final range Doppler map to prevent the amplification of thermal noise and remove the weight-norm variation as a function of Doppler is shown to be a critical step to allow interpretation and application of detection algorithms after STAP processing.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131526770","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":"Space-time adaptive processing for forward looking arrays","authors":"J. T. Caldwell, T. Hale","doi":"10.1109/NRC.2004.1316478","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316478","url":null,"abstract":"The paper applies space-time adaptive processing (STAP) to forward looking arrays. Traditionally, STAP research provides results for a side-looking array where a linear relationship exists between clutter Doppler and azimuth sine. This relationship does not hold in the forward looking case. Additionally, mainbeam clutter in the side-looking boresight case is range independent and, consequently, the clutter notch is always at zero hertz. In contrast, mainbeam clutter is range dependent in the forward looking case, resulting in multiple clutter notches for range ambiguous clutter. This range dependency corrupts the independent, identically distributed assumption required for the samples used in covariance estimation. The assumption can still be applied for a small data set, e.g., small range extent. Therefore, partially adaptive techniques with fewer degrees or freedom and correspondingly smaller sample support requirements must be used. Results are presented in the form of clutter power spectral density, signal-to-interference-plus-noise ratio, improvement factor, antenna patterns, and detection probability.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134353837","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 multiple hypotheses testing approach to radar detection and pre-classification","authors":"M. Greco, F. Gini, A. Farina","doi":"10.1109/NRC.2004.1316469","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316469","url":null,"abstract":"This work presents a single-scan-processing approach to the problem of detecting and pre-classifying a radar target that may belong to different target classes. The proposed method is based on a hybrid of the maximum a posteriori (MAP) and Neyman-Pearson (NP) criteria and guarantees the desired constant false alarm rate (CFAR) behavior. The targets are modeled as subspace random signals having zero mean and given covariance matrix. Different target classes are discriminated based on their different signal subspaces, which are specified by their covariance matrices. Performance is investigated by means of numerical analysis and Monte Carlo simulation in terms of probabilities of false alarm, detection and classification. The extra signal-to-noise power ratio necessary to preclassify a target once a detection has occurred is also derived.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131102071","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":"Efficient robust AMF using the enhanced FRACTA algorithm: results from KASSPER I & II [target detection]","authors":"S. Blunt, K. Gerlach","doi":"10.1109/NRC.2004.1316452","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316452","url":null,"abstract":"This paper presents further developments and results of the FRACTA algorithm which has been shown to be robust to nonhomogeneous environments containing outliers. The main focus here is upon the detection of targets in the KASSPER I challenge data cube which possesses dense clusters of targets and the highly nonhomogeneous KASSPER II data in which severe clutter is present over all ranges and Dopplers thereby hindering the identification of a dominant clutter ridge. The KASSPER II dataset is further exacerbated by dense clusters of targets as well as the presence of several deep shadow regions that not only prevent target detection but may also skew covariance matrix estimation. A doppler-dependent thresholding technique is developed which is then incorporated into the FRACTA.E framework and then applied to the KASSPER II dataset. Simulation results are compared with the standard sliding window scheme as well as when clairvoyant knowledge of the covariance matrices is employed. Results verify the improved performance of the FRACTA.E algorithm.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115294703","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":"Effect of the common process noise on performance of two-sensor fused-track","authors":"Zhao Jie, Xu Tao, Ren Lixiang, Cui Zhishe","doi":"10.1109/NRC.2004.1316426","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316426","url":null,"abstract":"This paper presented the effect of the common process noise on track statistical distance and performance of state estimation fusion. Because of the great computational load on the cross-covariance matrix produced by process noise, indeed, which is a half or total computational load, the real-time computation of the cross-covariance matrix is avoided in system implementation. First, the computational load on the cross-covariance matrix, track statistical distance, and state estimation fusion are estimated and compared. And the effect of the common process noise on track statistical distance and performance of state estimation fusion are simulated. Simulation results show that in the case of less process noise, the cross-covariance matrix is neglected.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124342003","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":"Classification of training data with reduced-rank generalized inner product","authors":"M. Tinston, W. Ogle, M. Picciolo, J. S. Goldstein","doi":"10.1109/NRC.2004.1316428","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316428","url":null,"abstract":"Selection of training data for space-time adaptive processing in radar systems remains one of the critical problems to be solved. The practical application of optimal detection theory relies on a large number of i.i.d. training samples. The required homogeneity is typically assumed to be satisfied by range cells adjacent to the cell under test. This is typically not valid in real-world applications. The generalized inner product has previously been proposed to assist in training data selection. This paper introduces two innovations: (1) the generalized inner product in the data-adaptive reduced-rank subspace of the multistage Wiener filter; and (2) classification of the available data into distinct, self-homogenous sets. Injected targets in recorded data from the MCARM program are used to assess performance. Training with data classified within the multistage Wiener filter subspace, also known as the Krylov subspace, is shown to outperform the conventional technique of selecting adjacent training cells.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116361666","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":"Peculiar radar cross-section properties of double-negative and single-negative metamaterials","authors":"A. Alú, N. Engheta","doi":"10.1109/NRC.2004.1316401","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316401","url":null,"abstract":"We give an overview of some of the results of our theoretical analysis of anomalous scattering phenomena for structures involving metamaterial layers, and we provide some physical insights and ideas for potential applications.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116160280","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}
P. Zulch, M. Davis, L. Adzima, R. Hancock, S. Theis
{"title":"The Earth rotation effect on a LEO L-band GMTI SBR and mitigation strategies","authors":"P. Zulch, M. Davis, L. Adzima, R. Hancock, S. Theis","doi":"10.1109/NRC.2004.1316390","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316390","url":null,"abstract":"Space based radars (SBR) have been used to accomplish a number of civilian and military missions. Most recently, SBR concepts have been considered to perform ground moving target indication (GMTI) radar modes. Unlike airborne surveillance platforms, SBR clutter returns are affected by the high satellite velocity and Earth rotation. The phenomenology of the Earth's rotation, and its impact on clutter Doppler returns, are discussed for a Low Earth Orbit (LEO) L-band radar concept. The USA Air Force's Research Laboratory Space Time Adaptive Processing Tool (RLSTAP) high fidelity radar modeling tool is used to provide simulated data in order to demonstrate the Earth rotation effects, and resulting clutter rejection impact on slow moving target detection.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116247845","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":"GLRT-detection performance in subsurface sounding","authors":"M. Sciotti, D. Pastina, P. Lombardo","doi":"10.1109/NRC.2004.1316481","DOIUrl":"https://doi.org/10.1109/NRC.2004.1316481","url":null,"abstract":"The performance of subsurface deep sounding is investigated with reference to the radar sounder, MARSIS (Mars advanced radar for subsurface and ionosphere sounding), aboard the Mars Express mission, designed to investigate the presence of water-related interfaces in the subsurface of Mars. The analysis aims at providing the necessary tools for (i) performance prediction and (ii) data processor design. Using well known models for the backscattered signal, we compare the expected signal-to-clutter ratio values under most of the instrument's operating conditions. The generalized likelihood ratio (GLR) approach is followed for subsurface interface detection, and along-track integration is introduced in order to achieve the desired performance. In particular, we address the design of the integration window, and the requirements of data homogeneity. A thorough performance analysis is presented to cope with the expected MARSIS scenarios. In particular, we investigate several sources of mismatch between the assumed model and collected data, and derive the performance degradation due to each source.","PeriodicalId":268965,"journal":{"name":"Proceedings of the 2004 IEEE Radar Conference (IEEE Cat. No.04CH37509)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123549538","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}