News Article | March 8, 2016
Abstract: The National Space Society congratulates the Space Solar Power D3 (SSPD3) team on sweeping the awards in a March 2 multi-departmental competition to find promising new technology ideas that could simultaneously advance diplomacy, defense and development (D3). The SSPD3 team proposal was titled "Carbon-Free Energy for Global Resilience and International Goodwill." "Our multi-agency industry team proposal was in the top 1% of ideas picked to present to the very senior panel including the Vice Chairman of the Joint Chiefs of Staff in the D3 Innovation Challenge, a first-of-a-kind contest for ideas sourced from across the Department of Defense, Department of State, and United States Agency for International Development by the Secretary of Defense and Secretary of State themselves," said team member Peter Garretson. "Our idea to start a national Space Solar Power Program won hands down, taking four of seven possible awards," he said. Space Solar Power (SSP) is an energy concept where an orbiting satellite gathers energy from sunlight in space and transmits it wirelessly to Earth. SSP can solve our energy and greenhouse gas emissions problems and provide large quantities of energy to each and every person on Earth with very little environmental impact. This was the first time that SSP was briefed at such a high level. The space solar power D3 team includes members of the Air Force's Air University, the Naval Research Lab, Northrop Grumman, NASA, the Joint Staff Logistics and Energy Division, the Defense Advanced Research Projects Administration, the Army, and the Space Development Steering Committee. "Space Solar Power has made a giant leap forward thanks to Paul Jaffe, Peter Garretson, and the rest of the team," said Dale Skran, NSS Executive Vice President and Chairman of the NSS Policy Committee, adding, "We at NSS look forward to continuing to promote SSP at the national and international levels." Space Solar Power is one of the milestones that NSS envisions on the road to a prosperous future where the resources of space come to benefit us on Earth. The NSS Roadmap to Space Settlement (www.nss.org/roadmap ) documents this and other milestones. NSS has also created the world's largest online library on SSP at nss.org/ssp. About National Space Society NSS is an independent nonprofit educational membership organization dedicated to the creation of a spacefaring civilization. NSS is widely acknowledged as the preeminent citizen's voice on space, with over 50 chapters in the United States and around the world. The Society publishes Ad Astra magazine, an award-winning periodical chronicling the most important developments in space. To learn more, visit www.nss.org. Biographies for the Garretson and Skran quotes can be found at www.nss.org/about/bios/garretson and www.nss.org/about/bios/skran.html. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
News Article | April 11, 2016
A team of scientists led by Dr. Paul Jaffe, spacecraft engineer at the U.S. Naval Research Laboratory (NRL), have been named winners of the first-ever Department of Defense (DoD) Diplomacy, Development, and Defense (D3) Innovation Summit Pitch Challenge, for the innovative concept to harness space-based solar energy to power terrestrial assets. Selected, March 2, from the top six innovation teams from across the DoD, Department of State (DoS) and the U.S. Agency for International Development (USAID), the NRL team was named winner in four of the seven possible award categories for Innovation, Presentation, Collaboration, and People's Choice. "The proposed approach entails collection of solar energy, its conversion to microwave energy, and the wireless transmission of the microwaves to the Earth," said Jaffe. "This offers the benefit of providing base-load power while avoiding diurnal cycles and atmospheric losses often associated with terrestrial solar power." The Secretary of Defense's Innovation Challenge is a groundbreaking interagency initiative intended to spur innovative thinking and to encourage collaboration on policy issues that matter most to our nation's security and prosperity, converging technological innovation with defense, diplomacy and development objectives. Comprised of members from the Department of State Bureau of Energy Implementation, Defense Advanced Projects Agency (DARPA), Joint Staff Logistics Directorate, Air Force's Air University Center for Space Innovation, and industry stakeholders Mankins Space Technology Inc. and Northrop Grumman, the team, according to Jaffe, seeks to empower global prosperity and security through a three-step program leading to an ambitious international on-orbit demo of an orbital power station within 10 years. "We are extremely excited and honored that this ambitious idea has been selected out of nearly 500 original entries," Jaffe said. "Other major powers around the world, particularly in Asia, are also investigating this idea in earnest, and it's gratifying to see interest in it domestically ... It's hard to overstate the significance and benefits of this concept if it comes to fruition." If successful, this project — based on an interagency proposal led by Jaffe entitled Carbon-Free Energy for Global Resilience and International Goodwill — will make possible the construction of huge platforms from tens of thousands of small elements that can deliver, remotely and affordably, tens of thousands of megawatts using wireless power transmissions. This novel approach to the challenge of space-based solar power will enlist the support of a world-class international team to determine the conceptual feasibility by means of integrated systems analyses, supported by selected "proof-of-concept" technology experiments. About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.
Ashraf U.,Air University
IEEE Transactions on Mobile Computing | Year: 2015
In this paper, we address the following problem: Given a specific deployment of a wireless mesh network and given a budget to augment the capacity of N links within the network, which links should be selected for capacity augmentation in order to maximize the achievable aggregate throughput for all the flows in the network? Unlike previous research which focuses on installing additional nodes or gateways, we work on an existing deployment of the mesh network and identify optimal link positions for capacity augmentation. We model the capacity augmentation problem in single-radio single-channel mesh networks as a multicommodity maximum flow problem and derive a mixed-integer linear programming model for identifying the optimal links for capacity augmentation. For ensuring fairness among flows, we propose a concurrent flow problem formulation and derive a corresponding mixed-integer linear programming model. We propose greedy algorithms to solve the mixed-integer linear programming formulations. We also extend our analysis to the case of multi-radio multi-channel networks in which additional radios can be deployed on nodes for capacity augmentation. The simulation results of the proposed schemes for several different topologies indicate that the proposed greedy algorithms are correct and provide exact results at a fraction of the cost. © 2014 IEEE.
Khan W.,Air University |
Mansoor Qureshi I.,Air University |
Sultan K.,Air University
IEEE Geoscience and Remote Sensing Letters | Year: 2014
In recent years, multiple-input-multiple-output (MIMO) radar has been receiving increasing attention from researchers due to its numerous benefits. In contrast to conventional radar systems, it offers increased spatial resolution and improved parameter estimation, target tracking, and recognition performance. Recently, a combination of phased-array radar and MIMO radar, which is called Phased-MIMO radar, has also been proposed and studied. The ambiguity function has been a traditional and effective tool to investigate the range and Doppler resolution of conventional radar systems and is now being extended for MIMO radar systems. In this letter, the ambiguity function of the Phased-MIMO radar with overlapping subarrays has been formulated, and some mathematical properties of the ambiguity function have been derived. These properties can help when comparing the performance of conventional and MIMO radar systems. This letter can be considered an extension of the work done by Chen and Vaidyanathan for MIMO radar systems. © 2004-2012 IEEE.
Rashid M.I.,Air University |
Akhtar S.,Air University
Proceedings of 2012 9th International Bhurban Conference on Applied Sciences and Technology, IBCAST 2012 | Year: 2012
In this paper, we propose an adaptive feedback control law for asymptotic attitude & altitude stabilization of a quadrotor using feedback of body axis angular rates, absolute orientation with respect to the inertial frame, altitude and altitude rate. No knowledge of quadrotor model parameters i.e. inertia matrix and mass is assumed. Stability of adaptive control law is shown via Lyapunov arguments. Simulation results are presented to demonstrate convergence of controller parameters and asymptotically perfect attitude & altitude stabilization of a quadrotor. © 2012 IEEE.
Arif M.,Air University
International Journal of Innovative Computing, Information and Control | Year: 2011
In this paper, a novel index called Arif Index is proposed to evaluate the discrimination power of the features in pattern classification. Optimizing the performance of a classifier requires a prior knowledge of maximum achievable accuracy in the pattern classification using a particular set of features. Moreover, it is also desirable to know that this set of features is separable by a decision boundary of any arbitrary complexity or not. Proposed index is model free and requires no clustering algorithm to discover the clustering structure present in the feature space. It is only based on the information of local neighborhood of feature vectors in the feature space. This index can be used to predict the classification accuracy and density of the feature vectors of a class in the feature space. It was found in this paper that predicted accuracy and Arif index are very strongly correlated with each other (R2 = 0.99 with ρ-value nearly equals to zero). This index is designed to predict the maximum achievable accuracy by a particular set of features. Implementation of the index is simple and time efficient. Performance of Arif index on different benchmark physiological data sets is found to he in consistent with the reported accuracies in the literature. Hence, this index will be very useful in providing prior useful information about the quality of features before designing any classifier. ICIC International © 2011.
Ahmed S.,Air University
IEEE Transactions on Aerospace and Electronic Systems | Year: 2014
A novel radar pulse integration technique is proposed in which the received signals in various returns from the target during one scan are multiplied with each other instead of the conventional summing up. Using the Mellin transform, mathematical expressions are derived that pave the way for computation of probability of detection and probability of false alarm in the context of this technique. Analytical and simulation results show that the proposed product-based pulse combining is more resistant to noise jamming, as compared to conventional noncoherent pulse integration, under certain conditions. © 2014 IEEE.
Khan W.,Air University |
Qureshi I.M.,Air University
IEEE Antennas and Wireless Propagation Letters | Year: 2014
In recent years, frequency diverse array radar with fixed frequency offset has been proposed and investigated. It has been shown that the beampattern of this category of radar is time-dependent as well as range-angle-dependent. In this letter, we have proposed time-dependent frequency offset to achieve a beampattern that is time-independent for a given pair of range and angle. The proposed radar system has been analyzed mathematically, and the simulation results are presented. Simulations show that the beampattern does not change with time for a particular range-angle pair, but it remains time-dependent for other values of range and angle. With the proposed radar system, the target remains illuminated constantly for the whole pulse duration, causing a high-energy reflection that can increase detectability of the target. © 2002-2011 IEEE.
Sadiq M.A.,Air University
Journal of the Physical Society of Japan | Year: 2011
In this paper steady streaming due to a vibrating sphere in an incompressible fluid is considered. The Vishik-Lyusternik method is employed to construct an asymptotic expansion of the solution of the Navier-Stokes equations in the limit of high-frequency vibrations for Reynolds numbers of O(1). The effect of the Stokes drift of fluid particles is also considered. © 2011 The Physical Society of Japan.
Ashraf U.,Air University
IEEE Communications Letters | Year: 2012
This letter proposes Interference-Aware Route Discovery (IARD) which is a joint resource-reservation and route-selection scheme for multi-radio multi-channel multi-rate 802.11 wireless multihop networks. IARD contributes by combining resource-reservation with route-selection, two previously disconnected areas of research in wireless multihop networks. IARD accurately models the multi-rate capability of wireless radios for resource estimation and reservation. IARD also exploits the multi-radio multi-channel capability of the network to minimize the impact of route discovery floods on existing QoS flows. © 2012 IEEE.