| 1. |
- Abdu, Tedros Salih, et al.
(författare)
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Demand-Aware Onboard Payload Processor Management for High Throughput NGSO Satellite Systems
- 2023
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9251. ; , s. 1-18
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Tidskriftsartikel (refereegranskat)abstract
- High-Throughput Satellite (HTS) systems with digital payload technology have been identified as a key enabler to support 5G/6G high-data connectivity with wider coverage area. The satellite community has extensively explored resource allocation methods to achieve this target. Typically, these methods do not consider the intrinsic architecture of the flexible satellite digital payload, which consists of multiple processors responsible for receiving, processing, and transmitting the signals. This paper presents a demand-aware onboard processor management scheme for broadband Non-Geostationary (NGSO) satellites. In this context, we formulate an optimization problem to minimize the number of active on-board processors while meeting the system constraints and user requirements. As the problem is non-convex, we solve it in two steps. First, we transform the problem into demand-driven bandwidth allocation while fixing the number of processors. Second, using the bandwidth allocation solution, we determine the required number of processors with two methods: 1) sequential optimization with the Branch & Bound method and 2) Bin Packing with Next Fit, First Fit, and Best Fit methods. Finally, we demonstrate the proposed methods with extensive numerical results. It is shown that the Branch & Bound, Best Fit, and First Fit methods manage the processors better than the Next Fit method. Furthermore, Branch & Bound requires fewer processors than the above methods.
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| 2. |
- Andersson, Fredrik, et al.
(författare)
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Fast Fourier Methods for Synthetic Aperture Radar Imaging
- 2012
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - 0018-9251. ; 48:1, s. 215-229
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Tidskriftsartikel (refereegranskat)abstract
- In synthetic aperture radar one wishes to reconstruct the reflectivity function of a region on the ground from a set of radar measurements taken at several angles. The ground reflectivity is found by interpolating measured samples, which typically lie on a polar grid in frequency space, to an equally spaced rectangular grid in frequency space, then computing an inverse Fourier transform. The classical Polar Format Algorithm (PFA) is often used to perform this interpolation. In this paper we describe two other methods for performing the interpolation and imaging efficiently and accurately. The first is the Gridding Method, which is widely used in the medical imaging community. The second method uses unequally spaced FFTs, a generic tool for arbitrary sampling geometries. We present numerical and computational comparisons of these three methods using both point scattering data and synthetic X-band radar reflectivity predictions of a construction backhoe.
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| 3. |
- Aoki, E. H., et al.
(författare)
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Labeling Uncertainty in Multitarget Tracking
- 2016
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 1557-9603 .- 0018-9251. ; 52:3, s. 1006-1020
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Tidskriftsartikel (refereegranskat)abstract
- In multitarget tracking, the problem of track labeling (assigning labels to tracks) is an ongoing research topic. The existing literature, however, lacks an appropriate measure of uncertainty related to the assigned labels that has a sound mathematical basis as well as clear practical meaning to the user. This is especially important in a situation where well separated targets move in close proximity with each other and thereafter separate again; in such a situation, it is well known that there will be confusion on target identities, also known as "mixed labeling." In this paper, we specify comprehensively the necessary assumptions for a Bayesian formulation of the multitarget tracking and labeling (MTTL) problem to be meaningful. We provide a mathematical characterization of the labeling uncertainties with clear physical interpretation. We also propose a novel labeling procedure that can be used in combination with any existing (unlabeled) MTT algorithm to obtain a Bayesian solution to the MTTL problem. One advantage of the resulting solution is that it readily provides the labeling uncertainty measures. Using the mixed labeling phenomenon in the presence of two targets as our test bed, we show with simulation results that an unlabeled multitarget sequential Monte Carlo (M-SMC) algorithm that employs sequential importance resampling (SIR) augmented with our labeling procedure performs much better than its "naive" extension, the labeled SIR M-SMC filter.
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| 4. |
- Backén, Staffan, et al.
(författare)
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RF replay system for narrowband GNSS if signals
- 2011
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - 0018-9251 .- 1557-9603. ; 47:1, s. 586-595
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Tidskriftsartikel (refereegranskat)abstract
- Although GNSS RF signal simulators have long possessed the capability to generate scenarios they are, for example, not yet able to model a realistic scenario with complex multipath. Software defined receivers bridge the gap between simulated and real data to the extent that they may offer a replay capability, where a data set is first recorded to disk and later can be processed several times. Unfortunately, the recorded data generally can not be used by other GNSS receivers, making receiver to receiver comparisons difficult and time consuming.This paper describes a system capable of replaying recorded IF data into any narrow bandwidth L1 GNSS receiver, including an evaluation of the difference (position, timing and SNR) between live and replayed data using a high sensitivity, consumer grade receiver. The performance of the replayed data set was found to match that of the live data.
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| 5. |
- Biswas, Sinchan, 1988-, et al.
(författare)
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Asymptotic Performance Analysis of Distributed Non-Bayesian Quickest Change Detection with Energy Harvesting Sensors
- 2022
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9251 .- 1557-9603. ; 58:4, s. 3697-3707
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Tidskriftsartikel (refereegranskat)abstract
- This paper focuses on the distributed non-Bayesian quickest change detection of the probability distribution of a random process in a wireless senor network (WSN), where the distributions before and after the change point is assumed to be known. The individual sensors are capable of harvesting energy from their surroundings. Each sensor decides to sense the observation signal depending on the available energy at its disposal. Once, a sensor decides to sense, it takes a sample of the observation signal and computes the log-likelihood ratio (LLR) of the aforementioned two distributions, if enough energy is available in its battery for sensing and processing the sample. On the other hand, if enough energy is not available, the sensor decides to abstain from the sensing process during that time slot and waits until a future time slot when it accumulates enough energy to perform the sensing and processing. Once a sensor computes the LLR, it uses that information to calculate the Cumulative Sum (CUSUM) test statsistic to arrive at a local decision about the change point. When a change is detected, these decisions are then sent to the FC (provided the transmitting sensor has enough energy to transmit the decision to the fusion centre successfully), where they are collated to form a single decision about the detection of the change point based on some pre-decided fusion rule. In this work, using asymptotic results on the detection delay for CUSUM tests for a single sensor, we have derived asymptotic results for the expected detection delay (when the change occurs) for three common fusion rules, namely, OR, AND and $r$ out of $N$ rule respectively. These results are analyzed for the scenario when the average harvested energy ($\mathit{\bar{H}}$) at each sensor is greater than or equal to the amount of energy required for sensing ($E_{s}$). We show that in such cases, the standard existing asymptotic results for CUSUM test holds for the local decisions. Consequently, we have determined corresponding results for the detection delay for decisions taken at the FC with the three aforementioned fusion rules by using the theory of order statistics. Numerical results are provided to support the theoretical claims.
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| 6. |
- Boström-Rost, Per, 1988-, et al.
(författare)
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PMBM Filter With Partially Grid-Based Birth Model With Applications in Sensor Management
- 2022
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 0018-9251 .- 1557-9603 .- 2371-9877. ; 58:1, s. 530-540
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Tidskriftsartikel (refereegranskat)abstract
- This article introduces a Poisson multi-Bernoulli mixture (PMBM) filter in which the intensities of target birth and undetected targets are grid-based. A simplified version of the Rao-Blackwellized point mass filter is used to predict the intensity of undetected targets and to initialize tracks of targets detected for the first time. The grid approximation can efficiently represents intensities with abrupt changes with relatively few grid points compared to the number of Gaussian components needed in conventional PMBM implementations. This is beneficial in scenarios where the sensors field of view is limited. The proposed method is illustrated in a sensor management setting, where trajectories of sensors with limited fields of view are controlled to search for and track the targets in a region of interest.
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| 7. |
- Boström-Rost, Per, 1988-, et al.
(författare)
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Sensor management for search and track using the Poisson multi-Bernoulli mixture filter
- 2021
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 0018-9251 .- 1557-9603. ; 57:5, s. 2771-2783
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Tidskriftsartikel (refereegranskat)abstract
- A sensor management method for joint multi-target search and track problems is proposed, where a single user-defined parameter allows for a trade-off between the two objectives. The multi-target density is propagated using the Poisson multi-Bernoulli mixture filter, which eliminates the need for a separate handling of undiscovered targets and provides the theoretical foundation for a unified search and track method. Monte Carlo simulations of two scenarios are used to evaluate the performance of the proposed method.
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| 8. |
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| 9. |
- Da Fontoura, A. A., et al.
(författare)
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Timing Assurance of Avionic Reconfiguration Schemes using Formal Analysis
- 2020
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Ingår i: IEEE Transactions on Aerospace and Electronic Systems. - : IEEE. - 0018-9251 .- 1557-9603. ; 56:1, s. 95-106
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Tidskriftsartikel (refereegranskat)abstract
- Reconfigurable avionics systems can tolerate faults by moving functionalities from failed components to another available system component. This paper proposes a distributed reconfigurable architecture for application migration from failed modules to working ones. The feasible system reconfiguration states are determined off-line to provide the expected configuration in foreseen situations. Model Checking is used to determine feasible configurations evaluating specific temporal properties. A case study is used to show the application of the presented approach as a proof of concept
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| 10. |
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