Abstract: Methods and systems for space situational awareness (SSA) demonstration are provided.

Abstract: Methods and systems for cyber secure data communications are provided. In some embodiments, a method for transmitting data comprises: performing a marker-based data encoding process to embed a digital watermark into each of a plurality of original data flows to be transmitted to a plurality of receivers; performing a non-orthogonal multiple access process to allocate transmission powers to the plurality of original data flows, such that the plurality of original data flows are simultaneously superposed on a carrier frequency to generate a superposed signal; performing a noise modulation process to modulate the superposed signal to generate a noise-like signal and a reference noise signal; transmitting the noise-like signal and the reference noise signal through orthogonally polarized antennas; and performing a portal-based data integrity analysis process to check whether a receiver in the plurality of receivers is compromised or manipulated.

Abstract: The present disclosure provides a method for fusion and inference with per-hop link quality measurements in frequency hopping satellite communication (SATCOM) systems. The method includes: grouping hops having a same SATCOM link set into one hop group such that the one hop group contains a plurality of same SATCOM link sets; grouping the measurement sets into one or more first measurement groups, based on a link identification; in the each first measurement group having the same link identification, further grouping the measurement sets having a same range of the signal amplitude measurements into one or more second measurement groups; obtaining interference conditions by associating second measurement groups of all links in each hop group based on hop identifications belonging to the second measurement groups.

Abstract: The present disclosure provides a gated range scanning linear frequency modulated continuous wave (LFMCW) radar structure, including: a frequency synthesizer, a first mixer, a second mixer, a first filter, and a third mixer. The frequency synthesizer is configured for generating a first local oscillating signal and a second local oscillating signal, a frequency of the first local oscillating signal varying in a frequency range, each frequency corresponding to a sub-range of a coverage range scanned by the LFMCW radar structure. The first mixer is configured for mixing a copy of a transmitted signal and the first local oscillating signal to generate a first output signal (the receiver's first local oscillator). The second mixer is configured for mixing the first output signal and a received signal from a receiving antenna to generate a second output signal that includes an intermediate frequency (IF) signal being received by the first filter.

Abstract: A systematic interferences mitigation design for protected satellite communications (SATCOM) is provided. An advanced channel coding is designed to provide coding gain for SATCOM even in the presence of synchronization errors because of unintentional and intentional radio frequency interferences (RFIs). A unified SATCOM system spectrum efficiency and energy efficiency performance model is developed with a unified interference model for SATCOM dynamic resource allocation (DRA). The SATCOM system DRA is designed with a game theoretic engine and link optimizations providing traffic control, power control, frequency hopping pattern selection, beamforming codebook selection, and modulation with coding agile waveform adaptations. The interferences mitigation design is implemented with software defined radio USRP and GNU-radio to maintain communication link quality of services (QoS).

Abstract: Method and system for detecting and tracking multiple moving targets based on wide-area motion imagery are provided. The method includes receiving a task request from a client; sending the task request to a local agent; acquiring to-be-processed images from the client, in response to the task request; calling an Hadoop API and checking a running status of a Hadoop system for an available resource in the Hadoop system; when a resource in the Hadoop system is available, pushing the to-be processed images to a back-end Hadoop distributed file system (HDFS); running tracking algorithms of multiple moving objects associated with the to-be-processed images to provide tracking results of the multiple moving objects; when the Hadoop system is completed in running the tracking algorithms, generating and sending a message to the local agent; and sending the tracking results of the multiple moving objects from the HDFS to the front-end database.

Abstract: In accordance with various embodiments, a method for uplink multiple accessing based on code division multiple access (CDMA) technology and a related system are provided. The method comprises: designing a practical uplink spreading waveform for a code division multiple access (CDMA) based SCN by leveraging a plurality of pseudorandom sequences and investigating a channel coding block and a modulation block for the CDMA based SCN; determining an uplink frequency sub-band division for the CDMA based SCN to optimize a tradeoff between a performance and an implementation cost of CDMA based SCN; and specifying a configuration of a control system of the CDMA based SCN.

Abstract: Method and system for predicting collision probability of space objects are provided. Space objects are allocated according to a total number thereof for parallel computation in a GPU device. Initial orbit states of the space objects are generated by an initial-orbit-state generation kernel of the GPU device. Orbit propagation for each space object is performed based on the initial orbit state to predict a state of each space object by an orbit propagation kernel of the GPU device. The predicted states of the space objects are collected by a predicted-orbit-state collection kernel of the GPU device. A real-time visualization and rendering of the predicted space objects are performed in a form of point cloud during interactions between CPU threads and GPU kernels. A CPU host predicts a collision probability of any two space objects among the multitude of space objects, according to the interactions between the CPU threads and the GPU kernels.

Abstract: Methods and systems for providing cyber security, wherein a computer with network access incorporates game theory and utilizes a honeypot to enhance game-theoretic developments over active and passive sensors. To numerically solve the uniquely three-sided game modeled cyber security problem, using a geometric solution based on three-dimensional (3D) action surface and action curve. The methods and systems determine whether the game problem has one Nash equilibrium, multiple Nash equilibriums, or no Nash equilibrium; checks whether the equilibrium is a mixed or pure Nash; and timely computes Nash equilibriums; and follows a fictitious play concept. The solution is adaptive and can be applied for any partially observed cyber security system.

Abstract: In accordance with various embodiments of the disclosed subject matter, a method and a system for detecting multiple objects from real-time images are provided. The method comprises: performing, using a CPU host, an image segmentation process to divide real-time input images into a plurality of image partitions; performing, by multiple GPUs, a fast block-wise registration process, a mark setting process, a background generation process, a foreground generation process based on a Hyper-Q computation infrastructure, and a support vector machine classification process; and generating, by the CPU host, visualization classification images.

Abstract: Methods and devices for spectrum sensing using sliding window energy detection are provided. A sliding window energy detection test having a number of continuously-performed tests can be analyzed according to a desired cumulative false alarm rate to provide a corresponding, testing threshold. Based on the testing threshold and target signal to noise ratio, a testing window length is selected such that the sliding window energy detection is performed for a minimum expected discrete detection time. A sliding window energy detector can then obtain the selected testing window length and the corresponding, testing threshold for spectrum sensing. The sliding window energy detector includes a sampling unit, a detection probability analyzer, a testing statistic generator, a false alarm analyzer, a comparing unit, and a declaring unit.

Abstract: Methods and devices for demonstrating three-player pursuit-evasion (PE) game are provided using a hardware-in-loop test-bed. Robots including pursuer robots and an evader robot are arranged on a solid surface. A drone is positioned flying above to oversee the robots to capture a video or an image sequence of the robots. A robot thread process and a drone thread process are implemented by a computer. In the robot thread process, a tracking-by-detection process is perform to provide a state of the robot including a location and a heading direction of the robot; a delay compensation is conducted; and a PE game is called to calculate a robot command. In the drone thread process, a drone control is calculated to make the drone follow an evader robot, the drone control is sent to the drone, and user commands are also checked.

Abstract: A joint transmission power control and a transponder communication system, transmitting a plurality of uplink signals to a bent pipe transponder, combining the plurality of uplink signals to generate a combined downlink signal, transmitting the combined downlink signal to a ground hub, performing an estimate and pre-qualification process by the plurality of down link signals to determine a selected waveform, perform the join transmission power control of uplink margins are satisfied.

Abstract: Various embodiments provide an anti-jamming method in a satellite communication (SATCOM) system. A waveform modulation is performed on a waveform of a source data to provide a modulated waveform transmitted to a transmitter and then to a receiver. The modulated waveform transmitted from the receiver is demodulated to provide a demodulated waveform. In response to interference, a game reasoning process is performed on the demodulated waveform to provide an anti-jamming adaptive waveform. By performing a game-optimal waveform modulation on the anti-jamming adaptive waveform, a frequency hopping process is used to guide the data transmission, such that the source data is transmitted with a minimal probability of being interfered.

Abstract: Routing methods are provided for IP-based Iridium like LEO polar satellite constellation network for finding a Manhattan path between a source node and a destination node. The routing methods can include identification of congested inter satellite links (ISLs). By selecting and using uncongested alternative paths, an original routing process can be converted into sub-routing processes each in a small scale of a Manhattan path region. Quality of Service (QoS) requirements such as delays and jitters can be incorporated into the routing methods, which leads to efficient routing and enhanced QoS-performance over the satellite constellation network. The disclosed routing methods can be suitable for real-time routing/rerouting applications under dynamic network conditions.