Pub Date : 2012-03-03DOI: 10.1109/AERO.2012.6187394
T. Sorensen, E. Pilger, B. Yost, M. Nunes, J. Differding
Ongoing and planned smallsat programs within NASA, the DoD, and academia have indicated a need to be able to routinely and efficiently operate multiple small spacecraft in support of science and technology missions. However, as the number of these missions is expected to grow rapidly, the associated costs to develop and operate unique ground control stations, tools, and networks may become prohibitive to the sponsoring organizations or universities. In order to inform and raise the awareness of the smallsat space operations community, the University of Hawai'i, NASA Ames Research Center, San Jose State University (SJSU) and American Institure of Aeronautics and Astronautics (AIAA) held a workshop entitled Plug `n' Play Mission Operations (PPMO) which held May 16-17, 2011 at the SJSU campus in San Jose, California. The purpose of the workshop was to foster collaboration and leveraging of existing and developing capabilities that may be collectively utilized by the smallsat community for space operations. Although the emphasis of the workshop was on small satellites, many of the techniques discussed would be applicable to large spacecraft mission operations as well. The workshop explored the adoption of standards and existing capabilities as well as the creation of new technologies that will enable space mission developers to plan, design, and operate their spacecraft using a common architecture in order to reduce cost and overall mission risk. The PPMO workshop investigated the various needs of the smallsat communities (military, civil and educational space) and also touched on existing systems and capabilities (such as GSFC's GMSEC, JPL's AMMOS, and NRL's CGA used in the MC3 program) and those under development (such as HSFL's COSMOS and ESA's GENSO). The workshop also held facilitated discussions organized into categories along the lines of Approaches (programmatic and related issues), Implementation (technical solutions and architectures), and Applications (concept of operations, mission types and users). This paper presents the results of this workshop and the path forward.
{"title":"Plug and Play Mission Operations","authors":"T. Sorensen, E. Pilger, B. Yost, M. Nunes, J. Differding","doi":"10.1109/AERO.2012.6187394","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187394","url":null,"abstract":"Ongoing and planned smallsat programs within NASA, the DoD, and academia have indicated a need to be able to routinely and efficiently operate multiple small spacecraft in support of science and technology missions. However, as the number of these missions is expected to grow rapidly, the associated costs to develop and operate unique ground control stations, tools, and networks may become prohibitive to the sponsoring organizations or universities. In order to inform and raise the awareness of the smallsat space operations community, the University of Hawai'i, NASA Ames Research Center, San Jose State University (SJSU) and American Institure of Aeronautics and Astronautics (AIAA) held a workshop entitled Plug `n' Play Mission Operations (PPMO) which held May 16-17, 2011 at the SJSU campus in San Jose, California. The purpose of the workshop was to foster collaboration and leveraging of existing and developing capabilities that may be collectively utilized by the smallsat community for space operations. Although the emphasis of the workshop was on small satellites, many of the techniques discussed would be applicable to large spacecraft mission operations as well. The workshop explored the adoption of standards and existing capabilities as well as the creation of new technologies that will enable space mission developers to plan, design, and operate their spacecraft using a common architecture in order to reduce cost and overall mission risk. The PPMO workshop investigated the various needs of the smallsat communities (military, civil and educational space) and also touched on existing systems and capabilities (such as GSFC's GMSEC, JPL's AMMOS, and NRL's CGA used in the MC3 program) and those under development (such as HSFL's COSMOS and ESA's GENSO). The workshop also held facilitated discussions organized into categories along the lines of Approaches (programmatic and related issues), Implementation (technical solutions and architectures), and Applications (concept of operations, mission types and users). This paper presents the results of this workshop and the path forward.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"144 1","pages":"1-13"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76230763","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187196
Hamed Gholizadeh, Mohammad Javad Valdan Zoej, B. Mojaradi
In this paper, a novel hyperspectral image clustering procedure, which is based upon the Fully Constrained Least Squares (FCLS) spectral unmixing method, is proposed. The proposed clustering method consists of three major steps: endmember extraction, unmixing procedure and hardening process via the winner-takes-all approach. To estimate the optimal number of endmembers, instead of using the background signal subspace identification methods, the number of endmembers is varied in a predefined interval and the commonly accepted VCA (Vertex Component Analysis) algorithm is employed to extract the endmembers' spectra. At each iteration, the bandwise Root Mean Square Error (RMSE) between the reconstructed image, obtained from estimated fractions. and the original image is computed and the mean of all bandwise RMSEs is regarded as a measure to choose the optimum number of endmembers. Experiments conducted on the Indian Pines challenging dataset proved the superiority of proposed method over the K-Means and Fuzzy c-Means methods in terms of the widely used Adjusted Rand Index measure.
{"title":"A novel hyperspectral image clustering method based on spectral unmixing","authors":"Hamed Gholizadeh, Mohammad Javad Valdan Zoej, B. Mojaradi","doi":"10.1109/AERO.2012.6187196","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187196","url":null,"abstract":"In this paper, a novel hyperspectral image clustering procedure, which is based upon the Fully Constrained Least Squares (FCLS) spectral unmixing method, is proposed. The proposed clustering method consists of three major steps: endmember extraction, unmixing procedure and hardening process via the winner-takes-all approach. To estimate the optimal number of endmembers, instead of using the background signal subspace identification methods, the number of endmembers is varied in a predefined interval and the commonly accepted VCA (Vertex Component Analysis) algorithm is employed to extract the endmembers' spectra. At each iteration, the bandwise Root Mean Square Error (RMSE) between the reconstructed image, obtained from estimated fractions. and the original image is computed and the mean of all bandwise RMSEs is regarded as a measure to choose the optimum number of endmembers. Experiments conducted on the Indian Pines challenging dataset proved the superiority of proposed method over the K-Means and Fuzzy c-Means methods in terms of the widely used Adjusted Rand Index measure.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"29 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87929034","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187047
K. Zacny, G. Paulsen, B. Mellerowicz, J. Craft, Chris McKay, B. Glass, A. Davila, M. Marinova, W. Pollard
In this paper we report on the development of a rotary-percussive sampling drill, LunarVader. The purpose of the drill is to penetrate at least 1 meter in icy-regolith and acquire sub-surface sample for science analysis and for the In Situ Resource Utilization (ISRU). The drill was tested in a lunar analog site of the Ross Island, in the Antarctic and inside the 3.5 meter vacuum chamber in ice-bound JSC-1a lunar soil simulant. In both cases, the drill reached ~1 meter depth in approximately one hour. The average power was 100 Watts and Weight on Bit was less than 100 Newton. This corresponds to the drilling energy of 100 Whr. In each case approximately 500 grams of sample was recovered and autonomously deposited into a sterile bag.
{"title":"LunarVader: Testing of a 1 meter lunar drill in a 3.5 meter vacuum chamber and in the Antarctic lunar analog site","authors":"K. Zacny, G. Paulsen, B. Mellerowicz, J. Craft, Chris McKay, B. Glass, A. Davila, M. Marinova, W. Pollard","doi":"10.1109/AERO.2012.6187047","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187047","url":null,"abstract":"In this paper we report on the development of a rotary-percussive sampling drill, LunarVader. The purpose of the drill is to penetrate at least 1 meter in icy-regolith and acquire sub-surface sample for science analysis and for the In Situ Resource Utilization (ISRU). The drill was tested in a lunar analog site of the Ross Island, in the Antarctic and inside the 3.5 meter vacuum chamber in ice-bound JSC-1a lunar soil simulant. In both cases, the drill reached ~1 meter depth in approximately one hour. The average power was 100 Watts and Weight on Bit was less than 100 Newton. This corresponds to the drilling energy of 100 Whr. In each case approximately 500 grams of sample was recovered and autonomously deposited into a sterile bag.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"6 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87596073","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187166
Y. Poberezhskiy
Digital image compression reduces the bandwidth, time, and energy needed for transmission of images and signals, as well as memory needed for their storage. However, it cannot solve the digitization problems. Recently proposed compressive sampling (or sensing) solves these problems by reducing the average number of projections required for representing images and signals through exploiting their sparsity. An alternative approach named compressive quantization solves identical problems by reducing the average number of bits required for the same purpose. It exploits statistical properties of images and signals, as well as specific features of quantizers. In this paper, the analysis and further development of compressive quantization used for digitization of images is combined with its comparison to compressive sampling. It is shown that compressive quantization simplifies the image digitization more significantly and provides more effective and less distorting compression than compressive sampling. Its practical realization is much easier than that of compressive sampling. The root causes of these advantages are revealed.
{"title":"Compressive quantization versus compressive sampling in image digitization","authors":"Y. Poberezhskiy","doi":"10.1109/AERO.2012.6187166","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187166","url":null,"abstract":"Digital image compression reduces the bandwidth, time, and energy needed for transmission of images and signals, as well as memory needed for their storage. However, it cannot solve the digitization problems. Recently proposed compressive sampling (or sensing) solves these problems by reducing the average number of projections required for representing images and signals through exploiting their sparsity. An alternative approach named compressive quantization solves identical problems by reducing the average number of bits required for the same purpose. It exploits statistical properties of images and signals, as well as specific features of quantizers. In this paper, the analysis and further development of compressive quantization used for digitization of images is combined with its comparison to compressive sampling. It is shown that compressive quantization simplifies the image digitization more significantly and provides more effective and less distorting compression than compressive sampling. Its practical realization is much easier than that of compressive sampling. The root causes of these advantages are revealed.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"43 1","pages":"1-20"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88067941","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187446
G. R. Rapacki
The US Supreme Court's holding in Bilski v Kappos limits software developers attempting to patent inventions using method claims. The Bilski holding limited the scope of business method patents to those that claim a method hosted on a machine or those that effect a transformation of a particular article into a different state or thing. While today's scope of method claims is more limited than before Bilski, inventors can still effectively patent software inventions. This paper presents practical suggestions for patenting software inventions described by a method claim. The Supreme Court's holding is discussed, then using a scenario of an interest in patenting a method of finding the roots of a polynomial, several claim formats will be reviewed.
{"title":"Practical steps for patenting software post Bilski","authors":"G. R. Rapacki","doi":"10.1109/AERO.2012.6187446","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187446","url":null,"abstract":"The US Supreme Court's holding in Bilski v Kappos limits software developers attempting to patent inventions using method claims. The Bilski holding limited the scope of business method patents to those that claim a method hosted on a machine or those that effect a transformation of a particular article into a different state or thing. While today's scope of method claims is more limited than before Bilski, inventors can still effectively patent software inventions. This paper presents practical suggestions for patenting software inventions described by a method claim. The Supreme Court's holding is discussed, then using a scenario of an interest in patenting a method of finding the roots of a polynomial, several claim formats will be reviewed.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"2018 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86360889","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187404
Steven. A. Larson, Steven. A. Larson
Cognitive bias is generally recognized as playing a significant role in virtually all domains of human decision making. Insight in to this role is informally built in to many of the system engineering practices employed in the aero space industry. The review process, for example, typically has features that help to counteract the effect of bias. This paper presents a discussion of how commonly recognized biases may affect the verification and validation process. Verifying and validating a system is arguably more challenging than development, both technically and cognitively. Whereas there may be a relatively limited number of options available for the design of a particular aspect of a system, there is a virtually unlimited number of potential verification scenarios that may be explored. The probability of any particular scenario occurring in operations is typically very difficult to estimate, which increases reliance on judgment that may be affected by bias. Implementing a verification activity often presents technical challenges that, if they can be overcome at all, often result in a departure from actual flight conditions (e.g., 1-g testing, simulation, time compression, artificial fault injection) that may raise additional questions about the meaningfulness of the results, and create opportunities for the introduction of additional biases. In addition to mitigating the biases it can introduce directly, the verification and validation process must also overcome the cumulative effect of biases introduced during all previous stages of development. A variety of cognitive biases will be described, with research results for illustration. A handful of case studies will be presented that show how cognitive bias may have affected the verification and validation process on recent JPL flight projects, identify areas of strength and weakness, and identify potential changes or additions to commonly used techniques that could provide a more robust verification and validation of future systems.
{"title":"Cognitive bias in the verification and validation of space flight systems","authors":"Steven. A. Larson, Steven. A. Larson","doi":"10.1109/AERO.2012.6187404","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187404","url":null,"abstract":"Cognitive bias is generally recognized as playing a significant role in virtually all domains of human decision making. Insight in to this role is informally built in to many of the system engineering practices employed in the aero space industry. The review process, for example, typically has features that help to counteract the effect of bias. This paper presents a discussion of how commonly recognized biases may affect the verification and validation process. Verifying and validating a system is arguably more challenging than development, both technically and cognitively. Whereas there may be a relatively limited number of options available for the design of a particular aspect of a system, there is a virtually unlimited number of potential verification scenarios that may be explored. The probability of any particular scenario occurring in operations is typically very difficult to estimate, which increases reliance on judgment that may be affected by bias. Implementing a verification activity often presents technical challenges that, if they can be overcome at all, often result in a departure from actual flight conditions (e.g., 1-g testing, simulation, time compression, artificial fault injection) that may raise additional questions about the meaningfulness of the results, and create opportunities for the introduction of additional biases. In addition to mitigating the biases it can introduce directly, the verification and validation process must also overcome the cumulative effect of biases introduced during all previous stages of development. A variety of cognitive biases will be described, with research results for illustration. A handful of case studies will be presented that show how cognitive bias may have affected the verification and validation process on recent JPL flight projects, identify areas of strength and weakness, and identify potential changes or additions to commonly used techniques that could provide a more robust verification and validation of future systems.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"14 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82819123","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187297
M. Trinidad, E. Zabrensky, A. Sengupta
The Mars Ascent Vehicle (MAV) is a critical mission element of the Mars Sample Return campaign that delivers the Martian sample from Mars surface to orbit for rendezvous with retrieving spacecraft and sample return to earth. The MAV design presents significant challenges in that it must fit in the Lander mission architecture, have a minimized total system mass (MAV and igloo/erector support system) with a mass goal of less than 360 kg, and deliver the 5 kg Martian sample payload to a 460 to 580km orbit. The MAV must also withstand the harsh Mars thermal environment for up to 9 months where power consumption for thermal conditioning and operation further impacts the mass allocation to the MAV. Northrop Grumman Aerospace Systems, in collaboration with NASA GRC and JPL, conducted a MAV system study and component definition under a National Research Announcement, NASA In-Space Propulsion program. The study investigated a two-stage liquid propulsion concept, an optimized MAV trajectory, guidance, navigation, and control, thermal requirements, MAV components, and MAV support systems. The results of the study and baseline MAV system design are presented in this report.
{"title":"Mars Ascent Vehicle system studies and baseline conceptual design","authors":"M. Trinidad, E. Zabrensky, A. Sengupta","doi":"10.1109/AERO.2012.6187297","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187297","url":null,"abstract":"The Mars Ascent Vehicle (MAV) is a critical mission element of the Mars Sample Return campaign that delivers the Martian sample from Mars surface to orbit for rendezvous with retrieving spacecraft and sample return to earth. The MAV design presents significant challenges in that it must fit in the Lander mission architecture, have a minimized total system mass (MAV and igloo/erector support system) with a mass goal of less than 360 kg, and deliver the 5 kg Martian sample payload to a 460 to 580km orbit. The MAV must also withstand the harsh Mars thermal environment for up to 9 months where power consumption for thermal conditioning and operation further impacts the mass allocation to the MAV. Northrop Grumman Aerospace Systems, in collaboration with NASA GRC and JPL, conducted a MAV system study and component definition under a National Research Announcement, NASA In-Space Propulsion program. The study investigated a two-stage liquid propulsion concept, an optimized MAV trajectory, guidance, navigation, and control, thermal requirements, MAV components, and MAV support systems. The results of the study and baseline MAV system design are presented in this report.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"116 1","pages":"1-13"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79364048","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187179
E. Young, R. Mellon, J. Percival, K. Jaehnig, J. Fox, T. Lachenmeier, B. Oglevie, M. Bingenheimer
The ST5000 is a star tracker developed at the University of Wisconsin and used in NASA's sounding rocket payloads. In order to demonstrate the ST5000's suitability for pointed balloon-borne telescopes, we flew an ST5000 on a stratospheric balloon on May 6, 2011. This flight addressed our four basic questions: will the ST5000 work from 120,000 ft (it does), what was the rms performance (about 0.6"), what angular rates of motion would cause the ST5000 to fail (greater than 0.5 degrees/sec) and could the ST5000 serve as a daytime star tracker (not without modifications). We will briefly present the results from the flight and describe the ST5000's quantitative performance. We will also describe the problems with background light as a function of wavelength, altitude and angle from the Sun. We will discuss approaches to improve the daytime performance using infrared detectors and longer focal lengths/reduced platescales. Solutions that have finer platescales have the potential to improve the star tracker's error signal to the 0.1" level, which is better than the diffraction limit of a one meter telescope at 5000 Å.
{"title":"Sub-arcsecond performance of the ST5000 star tracker on a balloon-borne platform","authors":"E. Young, R. Mellon, J. Percival, K. Jaehnig, J. Fox, T. Lachenmeier, B. Oglevie, M. Bingenheimer","doi":"10.1109/AERO.2012.6187179","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187179","url":null,"abstract":"The ST5000 is a star tracker developed at the University of Wisconsin and used in NASA's sounding rocket payloads. In order to demonstrate the ST5000's suitability for pointed balloon-borne telescopes, we flew an ST5000 on a stratospheric balloon on May 6, 2011. This flight addressed our four basic questions: will the ST5000 work from 120,000 ft (it does), what was the rms performance (about 0.6\"), what angular rates of motion would cause the ST5000 to fail (greater than 0.5 degrees/sec) and could the ST5000 serve as a daytime star tracker (not without modifications). We will briefly present the results from the flight and describe the ST5000's quantitative performance. We will also describe the problems with background light as a function of wavelength, altitude and angle from the Sun. We will discuss approaches to improve the daytime performance using infrared detectors and longer focal lengths/reduced platescales. Solutions that have finer platescales have the potential to improve the star tracker's error signal to the 0.1\" level, which is better than the diffraction limit of a one meter telescope at 5000 Å.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"132 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79639325","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187025
J. Burt, Bob Smith
In 1998, then-Vice President Al Gore proposed a mission to the Earth-Sun first Lagrange point (L1) to observe the Earth as a planet. This mission was named Triana, after the lookout on Christopher Columbus's fleet who is reputedly the first of the European explorers to see the new world. Triana mission development proceeded for 21 months and cost an estimated $249M (in FY07$) before it was de-manifested from the Space Shuttle. The spacecraft has been in a state of “Stable Suspension” since November 2001. After the mission was placed into suspension, it was renamed the Deep Space Climate Observatory (DSCOVR). This paper will cover an overview of the original mission and highlights of refurbishing this mission to launch 16 years after it started, plus an update on its currently planned mission architecture.
{"title":"Deep Space Climate Observatory: The DSCOVR mission","authors":"J. Burt, Bob Smith","doi":"10.1109/AERO.2012.6187025","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187025","url":null,"abstract":"In 1998, then-Vice President Al Gore proposed a mission to the Earth-Sun first Lagrange point (L1) to observe the Earth as a planet. This mission was named Triana, after the lookout on Christopher Columbus's fleet who is reputedly the first of the European explorers to see the new world. Triana mission development proceeded for 21 months and cost an estimated $249M (in FY07$) before it was de-manifested from the Space Shuttle. The spacecraft has been in a state of “Stable Suspension” since November 2001. After the mission was placed into suspension, it was renamed the Deep Space Climate Observatory (DSCOVR). This paper will cover an overview of the original mission and highlights of refurbishing this mission to launch 16 years after it started, plus an update on its currently planned mission architecture.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"32 1","pages":"1-13"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83299955","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 : 2012-03-03DOI: 10.1109/AERO.2012.6187140
H. El-Henawy, E. Abdoul-Fattah, M. Gamal, M. Attala, A. Hafez
This paper proposes a new fuzzy constant false alarm processor (FCFAR) for radar MTD systems. The proposed amplitude processor decides the fixed threshold value for the CFAR using fuzzy logic controller according three input variables. First input is the fast threshold from fifty serially averaged range cells. The second is the slow threshold from concatenated 500 averaged range cells. The third input is the signal to noise ratio at the RF stage of the radar system. The proposed processor is simulated under Matlab program environment on 1 million range cells data in additive white Gaussian noise (AWGN) with non-homogeneous background clutter and from 5 to 30 dB signal to noise ratio (S/N). The results show the superiority of the proposed FCFAR than the traditional systems used during the last decade.
{"title":"A new fuzzy CFAR processor for radar MTD systems","authors":"H. El-Henawy, E. Abdoul-Fattah, M. Gamal, M. Attala, A. Hafez","doi":"10.1109/AERO.2012.6187140","DOIUrl":"https://doi.org/10.1109/AERO.2012.6187140","url":null,"abstract":"This paper proposes a new fuzzy constant false alarm processor (FCFAR) for radar MTD systems. The proposed amplitude processor decides the fixed threshold value for the CFAR using fuzzy logic controller according three input variables. First input is the fast threshold from fifty serially averaged range cells. The second is the slow threshold from concatenated 500 averaged range cells. The third input is the signal to noise ratio at the RF stage of the radar system. The proposed processor is simulated under Matlab program environment on 1 million range cells data in additive white Gaussian noise (AWGN) with non-homogeneous background clutter and from 5 to 30 dB signal to noise ratio (S/N). The results show the superiority of the proposed FCFAR than the traditional systems used during the last decade.","PeriodicalId":6421,"journal":{"name":"2012 IEEE Aerospace Conference","volume":"52 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2012-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80874540","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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