In order to optimize test flow after the default flow is modified by a tester, a new software framework for the radar fault isolation is illustrated. This framework separates all mapping algorithms from test flows so ...In order to optimize test flow after the default flow is modified by a tester, a new software framework for the radar fault isolation is illustrated. This framework separates all mapping algorithms from test flows so as to modify flow and to insert mapping algorithm dynamically in testing process. Based on this framework, a kind of optimization method of test flow is proposed and studied. By defining an objective function, we can evaluate all candidate test flows so as to get an optimized flow. An example explains how to search the flow from candidate flows.展开更多
To measure miss distance for antiaircraft projectile,a radial velocity identification and positioning method with a single radar is proposed. By analyzing the spatial resolution of multi-frequency ranging radar,the di...To measure miss distance for antiaircraft projectile,a radial velocity identification and positioning method with a single radar is proposed. By analyzing the spatial resolution of multi-frequency ranging radar,the discrimination and testing model of this radar for multi-targets（ projectile and target） is established to analyze the systematic error of antiaircraft miss distance. Then through the aerial target flight test and contrast test with optical test equipment,the validity of the measurement method is verified. This newmethod has the potential to be used in the measurement of antiaircraft projectile miss distance.展开更多
To measure projectile attitude in space flight, based on continuous wave （CW） radar, a new micro-Doppler effect testing technique is developed in this paper. It also establishes radar testing model for attitude of f...To measure projectile attitude in space flight, based on continuous wave （CW） radar, a new micro-Doppler effect testing technique is developed in this paper. It also establishes radar testing model for attitude of flying projectile and resolve micro-Doppler effect of projectile motion attitude. By distinguishing and geting attitude parameters such as micro-motion period, this technique can in- tuitively estimate the flight stability of projectile, and the validity of this technique is proved accord- ing to flight tests.展开更多
The problem of detecting signal with multiple input mul-tiple output （MIMO） radar in correlated Gaussian clutter dominated scenario with unknown covariance matrix is dealt with. The gen-eral MIMO model, with widely ...The problem of detecting signal with multiple input mul-tiple output （MIMO） radar in correlated Gaussian clutter dominated scenario with unknown covariance matrix is dealt with. The gen-eral MIMO model, with widely separated sub-arrays and co-located antennas at each sub-array, is adopted. Firstly, the generalized likelihood ratio test （GLRT） with known covariance matrix is ob-tained, and then the Rao and Wald detectors are devised, which have proved that the Rao and Wald test coincide with GLRT detec-tor. To make the detectors fully adaptive, the secondary data with signal-free will be collected to estimate the covariance. The per-formance of the proposed detector is analyzed, however, it is just ancillary. A thorough performance assessment by several numer-ical examples is also given, which has considered the sense with co-located antennas configure of transmitters and receivers array. The results show that the performance the proposed adaptive de-tector is better than LJ-GLRT, and the loss can be acceptable in comparison to their non-adaptive counterparts.展开更多
On the basis of the canard configuration a contour stealth design including chiefly the wing, the fuselage and their connection type is projected. The prime project of a blended wing body vehicle with canard is provid...On the basis of the canard configuration a contour stealth design including chiefly the wing, the fuselage and their connection type is projected. The prime project of a blended wing body vehicle with canard is provided and through the change of the fuselage head form and the different fin disposals, the radar cross section (RCS) is optimized. The average value of RCS and the value of RCS in the ± 45 ° front sector for different designs are illustrated. The model measurement proves that the project having a sharp head fuselage and 30 ° angle double fin has the minimum value of RCS. The wind tunnel test to the model with RCS optimized proved that the vehicle project has excellent aerodynamic characteristics such as high lift curve slope, up to 26° stalling angle, high lift / drag ratio equal to 8, and also has low RCS value in the front sector and in the lateral sector.展开更多
A variety of faulty radar echoes may cause serious problems with radar data applications,especially radar data assimilation and quantitative precipitation estimates.In this study,＂test pattern＂ caused by test signal...A variety of faulty radar echoes may cause serious problems with radar data applications,especially radar data assimilation and quantitative precipitation estimates.In this study,＂test pattern＂ caused by test signal or radar hardware failures in CINRAD （China New Generation Weather Radar） SA and SB radar operational observations are investigated.In order to distinguish the test pattern from other types of radar echoes,such as precipitation,clear air and other non-meteorological echoes,five feature parameters including the effective reflectivity data percentage （Rz）,velocity RF （range folding） data percentage （RRF）,missing velocity data percentage （RM）,averaged along-azimuth reflectivity fluctuation （RNr,z） and averaged along-beam reflectivity fluctuation （RNa,z） are proposed.Based on the fuzzy logic method,a test pattern identification algorithm is developed,and the statistical results from all the different kinds of radar echoes indicate the performance of the algorithm.Analysis of two typical cases with heavy precipitation echoes located inside the test pattern are performed.The statistical results show that the test pattern identification algorithm performs well,since the test pattern is recognized in most cases.Besides,the algorithm can effectively remove the test pattern signal and retain strong precipitation echoes in heavy rainfall events.展开更多
t According to a general representation of physical scale factor of RCS for variance in the size of simply shaped scatterers, a novel RCS model-testing method is described. The computed results of the prototype scatte...t According to a general representation of physical scale factor of RCS for variance in the size of simply shaped scatterers, a novel RCS model-testing method is described. The computed results of the prototype scatterers by this method from the model-testing agree well with their measured values both for two kinds of simply shaped scatterers, cylinders and ladder-shaped plates.展开更多
The geological prospecting radar, a high-techuology rapidly developed in recent years, is used in the field of nondestructive testing and object detecting, in accordance with the reflection principle of high-frequency...The geological prospecting radar, a high-techuology rapidly developed in recent years, is used in the field of nondestructive testing and object detecting, in accordance with the reflection principle of high-frequency electromagnetic wave. It will be effective if there exists a large difference in the electromagnetic properties between an object body and its surroundings. The result of using the geological prospecting radar in detecting the concrete blocks with ber in the capital internatioual airport’s east runway is aualyed in detail herein. The introduction of the geological prospecting radar provides a new approach to nondotodive testing.展开更多
文摘In order to optimize test flow after the default flow is modified by a tester, a new software framework for the radar fault isolation is illustrated. This framework separates all mapping algorithms from test flows so as to modify flow and to insert mapping algorithm dynamically in testing process. Based on this framework, a kind of optimization method of test flow is proposed and studied. By defining an objective function, we can evaluate all candidate test flows so as to get an optimized flow. An example explains how to search the flow from candidate flows.
基金Supported by the National Natural Science Foundation of China(61174219,51677192)
文摘To measure miss distance for antiaircraft projectile,a radial velocity identification and positioning method with a single radar is proposed. By analyzing the spatial resolution of multi-frequency ranging radar,the discrimination and testing model of this radar for multi-targets（ projectile and target） is established to analyze the systematic error of antiaircraft miss distance. Then through the aerial target flight test and contrast test with optical test equipment,the validity of the measurement method is verified. This newmethod has the potential to be used in the measurement of antiaircraft projectile miss distance.
基金Supported by the National Natural Science Fundation of China(61174219)
文摘To measure projectile attitude in space flight, based on continuous wave （CW） radar, a new micro-Doppler effect testing technique is developed in this paper. It also establishes radar testing model for attitude of flying projectile and resolve micro-Doppler effect of projectile motion attitude. By distinguishing and geting attitude parameters such as micro-motion period, this technique can in- tuitively estimate the flight stability of projectile, and the validity of this technique is proved accord- ing to flight tests.
基金supported by the Fundamental Research Funds for the Central Universities (103.1.2-E022050205)
文摘The problem of detecting signal with multiple input mul-tiple output （MIMO） radar in correlated Gaussian clutter dominated scenario with unknown covariance matrix is dealt with. The gen-eral MIMO model, with widely separated sub-arrays and co-located antennas at each sub-array, is adopted. Firstly, the generalized likelihood ratio test （GLRT） with known covariance matrix is ob-tained, and then the Rao and Wald detectors are devised, which have proved that the Rao and Wald test coincide with GLRT detec-tor. To make the detectors fully adaptive, the secondary data with signal-free will be collected to estimate the covariance. The per-formance of the proposed detector is analyzed, however, it is just ancillary. A thorough performance assessment by several numer-ical examples is also given, which has considered the sense with co-located antennas configure of transmitters and receivers array. The results show that the performance the proposed adaptive de-tector is better than LJ-GLRT, and the loss can be acceptable in comparison to their non-adaptive counterparts.
文摘On the basis of the canard configuration a contour stealth design including chiefly the wing, the fuselage and their connection type is projected. The prime project of a blended wing body vehicle with canard is provided and through the change of the fuselage head form and the different fin disposals, the radar cross section (RCS) is optimized. The average value of RCS and the value of RCS in the ± 45 ° front sector for different designs are illustrated. The model measurement proves that the project having a sharp head fuselage and 30 ° angle double fin has the minimum value of RCS. The wind tunnel test to the model with RCS optimized proved that the vehicle project has excellent aerodynamic characteristics such as high lift curve slope, up to 26° stalling angle, high lift / drag ratio equal to 8, and also has low RCS value in the front sector and in the lateral sector.
基金supported by the National Key Program for Developing Basic Sciences under Grant 2012CB417202the National Natural Science Foundation of China under Grant No. 41175038, No. 41305088 and No. 41075023+4 种基金the Meteorological Special Project "Radar network observation technology and QC"the CMA Key project "Radar Operational Software Engineering"the Chinese Academy of Meteorological Sciences Basic ScientificOperational Projects "Observation and retrieval methods of micro-physics and dynamic parameters of cloud and precipitation with multi-wavelength Remote Sensing"Project of the State Key Laboratory of Severe Weather grant 2012LASW-B04
文摘A variety of faulty radar echoes may cause serious problems with radar data applications,especially radar data assimilation and quantitative precipitation estimates.In this study,＂test pattern＂ caused by test signal or radar hardware failures in CINRAD （China New Generation Weather Radar） SA and SB radar operational observations are investigated.In order to distinguish the test pattern from other types of radar echoes,such as precipitation,clear air and other non-meteorological echoes,five feature parameters including the effective reflectivity data percentage （Rz）,velocity RF （range folding） data percentage （RRF）,missing velocity data percentage （RM）,averaged along-azimuth reflectivity fluctuation （RNr,z） and averaged along-beam reflectivity fluctuation （RNa,z） are proposed.Based on the fuzzy logic method,a test pattern identification algorithm is developed,and the statistical results from all the different kinds of radar echoes indicate the performance of the algorithm.Analysis of two typical cases with heavy precipitation echoes located inside the test pattern are performed.The statistical results show that the test pattern identification algorithm performs well,since the test pattern is recognized in most cases.Besides,the algorithm can effectively remove the test pattern signal and retain strong precipitation echoes in heavy rainfall events.
文摘t According to a general representation of physical scale factor of RCS for variance in the size of simply shaped scatterers, a novel RCS model-testing method is described. The computed results of the prototype scatterers by this method from the model-testing agree well with their measured values both for two kinds of simply shaped scatterers, cylinders and ladder-shaped plates.
文摘The geological prospecting radar, a high-techuology rapidly developed in recent years, is used in the field of nondestructive testing and object detecting, in accordance with the reflection principle of high-frequency electromagnetic wave. It will be effective if there exists a large difference in the electromagnetic properties between an object body and its surroundings. The result of using the geological prospecting radar in detecting the concrete blocks with ber in the capital internatioual airport’s east runway is aualyed in detail herein. The introduction of the geological prospecting radar provides a new approach to nondotodive testing.
