Faculty Publications

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Publications by NITK Faculty

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Subject: search.filters.subject.Communication satellites

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    This paper presents a design & implementation methodology for FPGA based MIL-STD-1553 Remote Terminal Sub-System using DDC's BU-61580 device. The interesting part of this paper is that it presents a design of non-processor remote terminal sub-system. The glue logic is put on one FPGA of 176 pins which initializes the BU-61580 in RT mode at power-on. The FPGA design was done using Viewlogic & Actel packages. The simulation has shown the correct results which was then followed by the implementation. In this paper, the design is presented for 9 sensors among which 5 are analog and 4 are digital. For the purpose of testing the circuit, the analog & digital sensors are simulated through the computer.
    (ISRO Satellite Centre, Design and implementation of FPGA based non-processor MIL-STD-1553 remote terminal sub-system using DDC's BU-61580) Bhagyalakshmi, K.; Ramachandra, G.; Agrawal, V.K.; Subbanna Bhat, P.; Philar, S.R.
    1999
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    A Performance Evaluation of Location Prediction Position-Based Routing Using Real GPS Traces for VANET
    (Springer New York LLC barbara.b.bertram@gsk.com, 2018) Jaiswal, R.K.; Jaidhar, C.D.
    Vehicular ad-hoc network (VANET) is an emerging paradigm for road transportation which minimizes traffic, accidents and improves fuel efficiency. VANET uses the position of the vehicle obtained from satellite system such as global positioning system (GPS), global navigation satellite system, Compass and Galileo as a location id in position-based routing protocol. The position obtained from the satellite system is likely to have an error due to environmental and technical issues which effect the routing performance. Thus, this paper proposes a position-based routing protocol which uses Kalman filter based location prediction technique to improve routing performance by minimizing location error. The routing protocol performance is evaluated on NS-3.23 simulator with real time GPS traces and simulator generated mobility on Two-ray ground and Winner-II propagation model for 500 m transmission range. Further, performance is compared with other prediction-based routing protocol on the metrics of packet delivery ratio, average delay and throughput. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.
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    GNSS Spoofing Detection and Mitigation in Multireceiver Configuration via Tracklets and Spoofer Localization
    (Institute of Electrical and Electronics Engineers Inc., 2022) Pardhasaradhi, B.; Gunnery, G.; Vandana, G.S.; Srihari, P.; Aparna., P.
    Global navigation satellite systems (GNSS) sensors estimate its position, velocity, and time (PVT) using pseudorange measurements. When there is no interference, the pseudoranges are due to authentic satellites, and the bearings is distinguishable. Whereas, in the presence of any intentional interference source like spoofer, the pseudorange measurements owing to spurious signals and all the bearings from the same direction. These spurious attacks yield either no position or falsified position to the GNSS receiver. This paper proposes to install multiple GNSS receivers on a vehicle (assumed to be cooperative) to detect and mitigate the spoofing attack. While installing multiple GNSS receivers, we assume that each GNSS receiver's relative position vector (RPV) is assumed to be known to other GNSS receivers. The installed GNSS receivers use the extended Kalman filter (EKF) framework to estimate their PVT. We proposed to calculate the equivalent-measurement and equivalent-measurement covariance of each GNSS receiver in the Cartesian coordinates in the tracklet framework. These tracklets are translated to the vehicle center using RPV to obtain translated-Tracklets. The translated tracklet based generalized likelihood ratio test (GLRT) is derived to detect the spoofing attack at a given epoch. In addition to that, these translated-Tracklets are processed in a batch least square (LS) framework to obtain the vehicle position. Once the attack is detected at a specific epoch, it quantifies that the position information is false. Moreover, another spoofing test is also formulated using DOA of signals. Once both the tests confirm the spoofing attack, the spoofer localization is performed using pseudo-updated states of GNSS receivers and acquired bearings in the iterative least-squares (ILS) framework. Mitigation of spoofing attack can be achieved either by projecting a null beam in the direction of the spoofer or by launching a counter-Attack on the spoofer. The simulation results demonstrate that the proposed algorithm detects spoofing attacks and ensures continuity in the navigation track. As the number of satellite signals increases, the algorithms provide better position root mean square error (PRMSE) for GNSS receivers track, vehicle track, and spoofer localization. © 2013 IEEE.