| 1. |
- Rantakokko, Jouni, et al.
(författare)
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Accurate and Reliable Soldier and First Responder Indoor Positioning : Multi-Sensor Systems and Cooperative Localization
- 2011
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Ingår i: IEEE wireless communications. - : IEEE Communications Society. - 1536-1284 .- 1558-0687. ; 18:2, s. 10-18
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Tidskriftsartikel (refereegranskat)abstract
- A robust, accurate positioning system with seamless outdoor and indoor coverage is a highly needed tool for increasing safety in emergency response and military urban operations. It must be lightweight, small, inexpensive, and power efficient, and still provide meter-level accuracy during extended operations. GPS receivers, inertial sensors, and local radio-based ranging are natural choices for a multisensor positioning system. Inertial navigation with foot-mounted sensors is suitable as the core system in GPS denied environments, since it can yield meter-level accuracies for a few minutes. However, there is still a need for additional supporting sensors to keep the accuracy at acceptable levels during the duration of typical soldier and first responder operations. Suitable aiding sensors are three-axis magnetometers, barometers, imaging sensors, Doppler radars, and ultrasonic sensors. Furthermore, cooperative positioning, where first responders exchange position and error estimates in conjunction with performing radio-based ranging, is deemed a key technology. This article provides a survey on technologies and concepts for high accuracy soldier and first responder positioning systems, with an emphasis on indoor positioning.
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| 2. |
- Rantakokko, Jouni, et al.
(författare)
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Positioning of emergency personnel in rescue operations :
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Summary and recommendations Presently, GPS-equipped mobile phones are launched at a large scale, enabling a variety of positioning based services. Indeed, GPS is expected to be the future killer application for mobile phones and services. The concept of accurate positioning by technical means implies a large number of applications not only for the mass market, but also for rescue services, fire brigades, police forces, and military and so on. For professional and governmental safety-of-life services the current systems are far from usable and large efforts have to be concentrated on research and development. Technologies based on GPS and other satellite-based positioning systems alone are vulnerable and are expected to malfunction in indoor or challenging electromagnetic environments, or due to antagonistic measures. Satellite-based positioning is a key component in a robust communication and positioning system aimed for first responders. Satellite based positioning in combination with local radio-based positioning systems and dead-reckoning or inertial navigation systems are enablers to fulfill the users? requirements on accuracy and availability of the positioning service. Sweden is a competent player within security. Around 300 companies with some 22.000 employees have been identified within the area. Swedish industry, research institutes and universities are expected to take part in international consortiums within EU FP7, as well as being a player within DHS funded research and development within the personal positioning and navigation area. The market potential for professional and safety-of-life personal equipment for robust positioning and communication with suitable means for information presentation is significant. In the US and the EU there are some 2 million incident responders each. On a national level we count some 35.000 fire fighters, police, and military personnel in international operations. A migration of the technology to private end-consumers as implemented in consumer electronics opens up a gigantic market for wireless services within navigation, gaming, and position-awareness services. Within the project positioning of first responders in rescue operations, robust positioning has been studied. From a system perspective, technologies for positioning of personnel are key system components within a platform for positioning, information transfer for command and control, and information processing and presentation for the personnel at all levels. \? Systems for training are needed to introduce the end-user to the technology, and for training and simulation of novel strategies enabled by the technology. Stationary training systems can be implemented with state-of-the art positioning methods. Feedback from the end-user to the R&D community is instrumental in the specification and development of future means for positioning of first responders. A research infrastructure, or test-bed, for implementation and evaluation of robust positioning is an essential tool. \? The functionality of the equipment has to be robust against hostile electromagnetic environments, either due to the actual physical environment (indoor scenario, intersystem interference from nearby electronic equipment, scenario within a large steel constructions, or power plant, etc), or due to electronic warfare antagonistic actions. Research has to be performed in several areas such as channel characterization for radio positioning, quality of satellite signals subjected to interference, and integrity of sensor information due to external influences. \? Contemporary MEMS-technology provides small-size sensors with low energy consumption. The rapid development within sensor technologies enables data fusion from a plurality of sensors by digital signal processing. Fundamental issues within digital signal processing have to be studied in several fields, including methods to enhance sensor performance by incorporating behavioral modeling; fusion of digital information from a plurality of sensors; aspects of hardware implementation to fulfill requirements on size, weight and uptime, and software defined receivers for radio-based positioning, communication and mapping. In summary, future systems for positioning of first responders in rescue operations rely on the development of infra-structure aimed for end-users in a training scenario; and a platform for R&D-purposes. In parallel, fundamental issues have to be studied regarding the electromagnetic environment, as well as methodologies in digital signal processing.
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| 3. |
- Strömback, Peter, et al.
(författare)
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Foot-Mounted Inertial Navigation and Cooperative Sensor Fusion for Indoor Positioning
- 2010
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Ingår i: Proceedings of the 2010 International Technical Meeting of The Institute of Navigation. - 9781617381157 ; , s. 89-98
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Konferensbidrag (refereegranskat)abstract
- In this paper we examine the effect of introducing an opportunistic cooperative navigation approach between soldiers, or first responders, equipped with foot-mounted IMUs and UWB-ranging equipment. The foot-mounted navigation system is based on a 15-state Extended Kalman filter, utilizing zero-velocity updates. The addition of range measurements between cooperative units displayed a significant improvement of the navigation accuracy in the studied scenarios. This approach has the potential to enable accurate positioning for several minutes in GPS-denied environments. Furthermore, the performance of the UWB-ranging sensor is examined and the resulting error statistics and typical ranging distances are characterized in indoor environments.
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| 4. |
- Ahnström, Ulrika, et al.
(författare)
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Detection and direction-finding of spread spectrum signals using correlation and narrowband interference rejection
- 2003
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Ingår i: Nordic Matlab Conference 2003.
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Konferensbidrag (refereegranskat)abstract
- An algorithm for correlation-based detection of direct sequence spread spectrum signals with direction finding, including direction-filtering and narrow-band interference rejection, is implemented and evaluated in MATLAB. An analog noise-free signal is generated and sampled by a test-bed system. Numerical simulations are run based on data corrupted by mutually uncorrelated white Gaussian noise sequences, and also with recorded noise from two spatially separated HF radio receivers. The simulations and measurements show promising results for detection and direction-finding of covert wideband signals in low SNR and in presence of narrowband interferers. Direction filtering is shown to improve the results.
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| 5. |
- Amin, Shoaib, et al.
(författare)
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2D Extended envelope memory polynomial model for concurrent dual-band RF transmitters
- 2017
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Ingår i: International journal of microwave and wireless technologies. - : Cambridge University Press. - 1759-0795 .- 1759-0787. ; 9:8, s. 1619-1627
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Tidskriftsartikel (refereegranskat)abstract
- The paper presents a 2D extended envelope memory polynomial (2D-EEMP) model for concurrent dual-band radio frequency (RF) power amplifiers (PAs). The model is derived based on the physical knowledge of a dual-band RF PA. The derived model contains cross-modulation terms not included in previously published models; these terms are found to be of importance for both behavioral modeling and digital pre-distortion (DPD). The performance of the derived model is evaluated both as the behavioral model and DPD, and the performance is compared with state-of-the-art2D-DPD and dual-band generalized memory polynomial (DB-GMP) models. Experimental result shows that the proposed model resulted in normalized mean square error (NMSE) of -51.7/-51.6dB and adjacent channel error power ratio (ACEPR) of -63.1/-63.4 dB, for channel 1/2, whereas the 2D-DPD resulted in the largest model error and DB-GMP resulted in model parameters that are 3 times more than those resulted with the proposed model with the same performance. As pre-distorter, the proposed model resulted in adjacent channel power ratio (ACPR) of -55.8/ -54.6 dB for channel 1/2 and is 7-10 dB lower than those resulted with the 2D-DPD model and2-4 dB lower compared to the DB-GMP model.
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| 6. |
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| 7. |
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| 8. |
- Andersson, Tomas, et al.
(författare)
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Frequency estimation utilizing the Hadamard transform
- 2001
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Ingår i: 2001 IEEE WORKSHOP ON STATISTICAL SIGNAL PROCESSING PROCEEDINGS. - NEW YORK : IEEE. - 0780370112 ; , s. 409-412
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Konferensbidrag (refereegranskat)abstract
- Fast analog to digital conversion with only one bit per sample does not only make high sampling rates possible but also reduces the required hardware complexity. For short data buffers or block lengths, it has been shown that tone frequency estimators can be implemented by a simple table look-up. In this paper we present an analysis of such tables using the Hadamard transform. As an outcome of the analysis, we propose a class of nonlinear estimators of low complexity. Their performance is evaluated using numerical simulations. Comparisons are made with the proper Cramer-Rao bound and with the table look-up approach.
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| 9. |
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| 10. |
- Andersson, Tomas, et al.
(författare)
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IEEE standard 1057, Cramer-Rao bound and the parsimony principle
- 2006
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9456 .- 1557-9662. ; 55:1, s. 44-53
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Tidskriftsartikel (refereegranskat)abstract
- This paper deals with some fundamental properties of the sine-wave-fit algorithm included in IEEE Standards 1057 and 1241. Asymptotic Cramer-Rao bounds (CRBs) for three and four model parameters are derived under the Gaussian assumption. Further, the sine-wave-fitting properties of the algorithm are analyzed by the parsimony principle. A decision criterion whether to use the three- or four-parameter model is derived. It is shown that a three-parameter sine-wave fit produces a better fit than the four-parameter fit if the frequency is known to be within an interval related to the number of samples and the signal-to-noise ratio. By a numerical analysis, the theoretical results are shown to be also valid for the uniform noise model of quantization.
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