Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201198
Li Neng-jing
Three schemes of low-altitude coverage over ground by air surveillance radars are discussed. They are the ground radar netting, the balloon lifted radars, and the AEW (airborne early warning) system. The cost-effectiveness of each scheme is analyzed and compared with others. The results show that for peacetime use the balloon radar is the best and AEW the worst, but in wartime the conclusion is reversed.<>
{"title":"A study of cost-effectiveness of low altitude coverage over ground by air surveillance radars","authors":"Li Neng-jing","doi":"10.1109/RADAR.1990.201198","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201198","url":null,"abstract":"Three schemes of low-altitude coverage over ground by air surveillance radars are discussed. They are the ground radar netting, the balloon lifted radars, and the AEW (airborne early warning) system. The cost-effectiveness of each scheme is analyzed and compared with others. The results show that for peacetime use the balloon radar is the best and AEW the worst, but in wartime the conclusion is reversed.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124028972","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201102
M. Cohen, M. R. Fox, J. M. Baden
The length 40 to 48 minimum peak sidelobe (MPS) codes have been discovered and enumerated. This discovery was made possible by utilizing innovative, recursive algorithms that make it unnecessary to search large numbers of the 2/sup N/ code possibilities while retaining the efficacy of an exhaustive search. It is noted that there are no length 49 or 50 biphase codes with peak sidelobes of three or less. The discovered MPS codes are analyzed for: (1) various properties such as Doppler tolerance and integrated sidelobe levels relating to pulse compression performance, and (2) various properties that might provide clues for finding longer, well-behaved codes. It is shown that one can obtain about +or-10/sup degrees / per pulse of improved Doppler tolerance by a judicious choice of code.<>
{"title":"Minimum peak sidelobe pulse compression codes","authors":"M. Cohen, M. R. Fox, J. M. Baden","doi":"10.1109/RADAR.1990.201102","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201102","url":null,"abstract":"The length 40 to 48 minimum peak sidelobe (MPS) codes have been discovered and enumerated. This discovery was made possible by utilizing innovative, recursive algorithms that make it unnecessary to search large numbers of the 2/sup N/ code possibilities while retaining the efficacy of an exhaustive search. It is noted that there are no length 49 or 50 biphase codes with peak sidelobes of three or less. The discovered MPS codes are analyzed for: (1) various properties such as Doppler tolerance and integrated sidelobe levels relating to pulse compression performance, and (2) various properties that might provide clues for finding longer, well-behaved codes. It is shown that one can obtain about +or-10/sup degrees / per pulse of improved Doppler tolerance by a judicious choice of code.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121770678","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201086
K. C. Indukumar, V. Reddy
It is shown that the effective dimension of the signal subspace collapses in the presence of multipath and may be recovered with subarray averaging. The F-norm (Frobenius norm) of the cross-correlation matrix is proposed as a measure of the correlation between the impinging signals, and an upper bound on this norm, which depicts all the essential features of the true F-norm, is derived. Using this bound, how the correlation between the direct and multipath signals falls with progressive smoothing and how the rate is which it falls depends on the spacing and directions of the sources are studied. Computer simulations are provided to support theoretical predictions. To keep the notation and the analysis simple, the analysis was restricted to two-source models; however, the results extend to signal models with more than two sources.<>
{"title":"Broad-band DOA estimation and beamforming in multipath environment","authors":"K. C. Indukumar, V. Reddy","doi":"10.1109/RADAR.1990.201086","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201086","url":null,"abstract":"It is shown that the effective dimension of the signal subspace collapses in the presence of multipath and may be recovered with subarray averaging. The F-norm (Frobenius norm) of the cross-correlation matrix is proposed as a measure of the correlation between the impinging signals, and an upper bound on this norm, which depicts all the essential features of the true F-norm, is derived. Using this bound, how the correlation between the direct and multipath signals falls with progressive smoothing and how the rate is which it falls depends on the spacing and directions of the sources are studied. Computer simulations are provided to support theoretical predictions. To keep the notation and the analysis simple, the analysis was restricted to two-source models; however, the results extend to signal models with more than two sources.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"315 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131021930","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201093
D. J. Strausberger, N.F. Chamberlain, F. Garber, E. Walton
The effects of a class of multipath propagation channels on the performance of a radar target classification system are considered. A Rician frequency-selective fading channel model is used to characterize the effects of the multipath propagation medium and evaluate the performances of radar target classification systems. The performances of classification algorithms that use relative amplitude, relative phase, and absolute amplitude measurements as features are investigated. Performance estimates of the various classification algorithms for interesting sets of channel parameters are obtained by means of Monte Carlo simulations.<>
{"title":"Modeling and performance of HF/OTH radar target classification systems","authors":"D. J. Strausberger, N.F. Chamberlain, F. Garber, E. Walton","doi":"10.1109/RADAR.1990.201093","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201093","url":null,"abstract":"The effects of a class of multipath propagation channels on the performance of a radar target classification system are considered. A Rician frequency-selective fading channel model is used to characterize the effects of the multipath propagation medium and evaluate the performances of radar target classification systems. The performances of classification algorithms that use relative amplitude, relative phase, and absolute amplitude measurements as features are investigated. Performance estimates of the various classification algorithms for interesting sets of channel parameters are obtained by means of Monte Carlo simulations.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124586608","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201135
S. Barbarossa, A. Farina
A novel scheme for detecting moving targets with synthetic aperture radar (SAR) is presented. The proposed approach is based on the use of the Wigner-Ville distribution (WVD) for simultaneously detecting moving targets and estimating their motion kinematic parameters. The estimation plays a key role for focusing the target and correctly locating it with respect to the stationary background. The method has a number of advantages: the detection is efficiently performed on the samples in the time-frequency domain, provided the WVD, without resorting to the use of a bank of filters, each one matched to possible values of the unknown target motion parameters; and the estimation of the target motion parameters can be done on the same time-frequency domain by locating the line where the maximum energy of the WVD is concentrated. A validation of the approach is given by both analytical and simulation means. In addition, the estimation of the target kinematic parameters and the corresponding image focusing are also demonstrated.<>
{"title":"A novel procedure for detecting and focusing moving objects with SAR based on the Wigner-Ville distribution","authors":"S. Barbarossa, A. Farina","doi":"10.1109/RADAR.1990.201135","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201135","url":null,"abstract":"A novel scheme for detecting moving targets with synthetic aperture radar (SAR) is presented. The proposed approach is based on the use of the Wigner-Ville distribution (WVD) for simultaneously detecting moving targets and estimating their motion kinematic parameters. The estimation plays a key role for focusing the target and correctly locating it with respect to the stationary background. The method has a number of advantages: the detection is efficiently performed on the samples in the time-frequency domain, provided the WVD, without resorting to the use of a bank of filters, each one matched to possible values of the unknown target motion parameters; and the estimation of the target motion parameters can be done on the same time-frequency domain by locating the line where the maximum energy of the WVD is concentrated. A validation of the approach is given by both analytical and simulation means. In addition, the estimation of the target kinematic parameters and the corresponding image focusing are also demonstrated.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130017947","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201193
W. Klembowski
Good weather angels are echoes detected by a radar when in the searched volume of air space no real objects exist. Experimental work is presented to show how the polarization state affects the intensity of good weather angels. Experimental data have been collected from the L-band long-range Polish primary surveillance radars (PSRs) (AVIA C) by registration of plots from the extractor and by taking pictures from the PPI presentation. The best results in decreasing the intensity of angels were obtained when using circular or near-circular polarization. It is concluded from the experimental data that fixed circular polarization can be used in PSRs as the best way to minimize received weather clutter and angels.<>
{"title":"Experimental study of polarization influence on angles intensity","authors":"W. Klembowski","doi":"10.1109/RADAR.1990.201193","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201193","url":null,"abstract":"Good weather angels are echoes detected by a radar when in the searched volume of air space no real objects exist. Experimental work is presented to show how the polarization state affects the intensity of good weather angels. Experimental data have been collected from the L-band long-range Polish primary surveillance radars (PSRs) (AVIA C) by registration of plots from the extractor and by taking pictures from the PPI presentation. The best results in decreasing the intensity of angels were obtained when using circular or near-circular polarization. It is concluded from the experimental data that fixed circular polarization can be used in PSRs as the best way to minimize received weather clutter and angels.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130578908","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201136
H. Klausing, H. Kaltschmidt
ROSAR (rotor-SAR) is a synthetic aperture radar concept for pilot sight target detection and target localization with high resolution. ROSAR is based on illuminating/receiving antennas placed at the tips of helicopter rotor blades. The ROSAR concept has potential benefits for civil and military helicopter-borne imaging applications. The concept has two main potential benefits: the imaging field of view is 360 degrees , and there is no need for a forward velocity of the carrier platform. As opposed to SAR systems based on linear movement of the antenna, ROSAR imaging is based on synthetic apertures of a circular shape. Thus, the image formation process requires a polar format processing architecture.<>
{"title":"Feasibility of a synthetic aperture radar with rotating antennas (ROSAR)","authors":"H. Klausing, H. Kaltschmidt","doi":"10.1109/RADAR.1990.201136","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201136","url":null,"abstract":"ROSAR (rotor-SAR) is a synthetic aperture radar concept for pilot sight target detection and target localization with high resolution. ROSAR is based on illuminating/receiving antennas placed at the tips of helicopter rotor blades. The ROSAR concept has potential benefits for civil and military helicopter-borne imaging applications. The concept has two main potential benefits: the imaging field of view is 360 degrees , and there is no need for a forward velocity of the carrier platform. As opposed to SAR systems based on linear movement of the antenna, ROSAR imaging is based on synthetic apertures of a circular shape. Thus, the image formation process requires a polar format processing architecture.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121808882","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201094
E. R. Billam
Solid-state active phased array radar is examined in the context of the widely reported developments in the reduction of the radar cross sections of military targets. It is shown that this form of radar makes the optimum use of power and aperture and is an increasingly attractive approach for the detection of small targets. The possibilities for the generation of high powers with solid-state phased arrays are demonstrated, and the potential performance of a solid-state active phased array radar is presented. Such related technical issues as high power sources, efficiency, duty factor, and heat removal, together with the increased levels of clutter associated with high sensitivity radar, are discussed.<>
{"title":"Phased array radar and the detection of 'low observables'","authors":"E. R. Billam","doi":"10.1109/RADAR.1990.201094","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201094","url":null,"abstract":"Solid-state active phased array radar is examined in the context of the widely reported developments in the reduction of the radar cross sections of military targets. It is shown that this form of radar makes the optimum use of power and aperture and is an increasingly attractive approach for the detection of small targets. The possibilities for the generation of high powers with solid-state phased arrays are demonstrated, and the potential performance of a solid-state active phased array radar is presented. Such related technical issues as high power sources, efficiency, duty factor, and heat removal, together with the increased levels of clutter associated with high sensitivity radar, are discussed.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123545136","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201195
J. P. Skura, C. Schemm, H. W. Ko, L. P. Manzi
The enhancement of the capability of electromagnetic parabolic equation (EMPE) and other propagation codes by using predictions from an atmospheric forecast model to provide refractivity data for range-dependent and time-varying situations is demonstrated. Starting from measured temperature and humidity data at one location and time, the JHU/APL planetary boundary layer model is used to obtained predictions for a 24-h forecast period. Predicted fields of temperature, humidity, and refractivity after 12 and 24 h are compared with measured data to verify the forecast, and vertical profiles of refractivity for each hour are provided, along with appropriate radar parameters, as input to EMPE. The EMPE calculations of expected radiation patterns as functions of height and range at selected times demonstrate the effects of hourly changes in the structure of the lower atmosphere on radar propagation. The radar propagation calculations have been repeated using the IREPS code to illustrate the similarities and differences between the two models when applied to this somewhat idealized, horizontally homogeneous situation.<>
{"title":"Radar coverage predictions through time- and range-dependent refractive atmospheres with planetary boundary layer and electromagnetic parabolic equation models","authors":"J. P. Skura, C. Schemm, H. W. Ko, L. P. Manzi","doi":"10.1109/RADAR.1990.201195","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201195","url":null,"abstract":"The enhancement of the capability of electromagnetic parabolic equation (EMPE) and other propagation codes by using predictions from an atmospheric forecast model to provide refractivity data for range-dependent and time-varying situations is demonstrated. Starting from measured temperature and humidity data at one location and time, the JHU/APL planetary boundary layer model is used to obtained predictions for a 24-h forecast period. Predicted fields of temperature, humidity, and refractivity after 12 and 24 h are compared with measured data to verify the forecast, and vertical profiles of refractivity for each hour are provided, along with appropriate radar parameters, as input to EMPE. The EMPE calculations of expected radiation patterns as functions of height and range at selected times demonstrate the effects of hourly changes in the structure of the lower atmosphere on radar propagation. The radar propagation calculations have been repeated using the IREPS code to illustrate the similarities and differences between the two models when applied to this somewhat idealized, horizontally homogeneous situation.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128854399","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}
Pub Date : 1990-05-07DOI: 10.1109/RADAR.1990.201114
R. D. Chaney, M. Burl, L. Novak
The performance of six polarimetric target detection algorithms is analyzed. The detection performance of the optimal polarimetric detector (OPD), the identity-likelihood-ratio-test (ILRT), the polarimetric whitening filter (PWF), the single-polarimetric-channel detector, the span detector, and the power maximization synthesis (PMS) detector is compared. Results for both probabilistic and deterministic targets in the presence of complex-Gaussian clutter are presented. The results of these studies indicate that the PWF and the ILRT typically achieve near optimal performance. Each remaining detection algorithm typically yields performance that is degraded compared to the performance of the OPD, the PWF, and the ILRT.<>
{"title":"On the performance of polarimetric target detection algorithms","authors":"R. D. Chaney, M. Burl, L. Novak","doi":"10.1109/RADAR.1990.201114","DOIUrl":"https://doi.org/10.1109/RADAR.1990.201114","url":null,"abstract":"The performance of six polarimetric target detection algorithms is analyzed. The detection performance of the optimal polarimetric detector (OPD), the identity-likelihood-ratio-test (ILRT), the polarimetric whitening filter (PWF), the single-polarimetric-channel detector, the span detector, and the power maximization synthesis (PMS) detector is compared. Results for both probabilistic and deterministic targets in the presence of complex-Gaussian clutter are presented. The results of these studies indicate that the PWF and the ILRT typically achieve near optimal performance. Each remaining detection algorithm typically yields performance that is degraded compared to the performance of the OPD, the PWF, and the ILRT.<<ETX>>","PeriodicalId":441674,"journal":{"name":"IEEE International Conference on Radar","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126579433","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}
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