There is an increasing demand for efficient and accurate indoor signal propagation prediction too... more There is an increasing demand for efficient and accurate indoor signal propagation prediction tools. A novel semi-deterministic approach based on a simple ray launching technique, the Monte Carlo method, and general statistics is developed. Without complicated calculations, all the electromagnetic issues, including diffuse scattering, are taken into account in the prediction using a new "motif concept". The motif model based on this approach is developed, implemented and tested. The signal strength as well as wide-band parameters can be predicted at very high speed. Software implementation of the model and first evaluations prove good performance and accuracy. A three-dimensional enhancement of the model is proposed
Page 1. Rao-Blackwellized Particle Filter for Pattern Matching Indoor Localisation Sigit Basuki W... more Page 1. Rao-Blackwellized Particle Filter for Pattern Matching Indoor Localisation Sigit Basuki Wibowo, Martin Klepal NIMBUS Centre for Embedded Systems Research Cork Institute of Technology Cork, Ireland Email: {sigit.wibowo, martin.klepal}@cit.ie ...
For professional users such as firefighters and other first responders, GNSS positioning technolo... more For professional users such as firefighters and other first responders, GNSS positioning technology (GPS, assisted GPS) can satisfy outdoor positioning requirements in many instances. However, there is still a need for high-performance deep indoor positioning for use by these same professional users. This need has already been clearly expressed by various communities of end users in the context of WearIT@Work, an R&D project funded by the European Community's Sixth Framework Program. It is known that map matching can help for indoor pedestrian navigation. In most previous research, it was assumed that detailed building plans are available. However, in many emergency / rescue scenarios, only very limited building plan information may be at hand. For example a building outline might be obtained from aerial photographs or cataster databases. Alternatively, an escape plan posted at the entrances to many building would yield only approximate exit door and stairwell locations as well as hallway and room orientation. What is not known is how much map information is really required for a USAR mission and how much each level of map detail might help to improve positioning accuracy. Obviously, the geometry of the building and the course through will be factors consider. The purpose of this paper is to show how a previously published Backtracking Particle Filter (BPF) can be combined with different levels of building plan detail to improve PDR performance. A new in/out scenario that might be typical of a reconnaissance mission during a fire in a two-story office building was evaluated. Using only external wall information, the new scenario yields positioning performance (2.56 m mean 2D error) that is greatly superior to the PDR-only, no map base case (7.74 m mean 2D error). This result has a substantial practical significance since this level of building plan detail could be quickly and easily generated in many emergency instances. The technique could be used to mitigate- - heading errors that result from exposing the IMU to extreme operating conditions. It is hoped that this mitigating effect will also occur for more irregular paths and in larger traversed spaces such as parking garages and warehouses.
Installations of IEEE 802.11-based wireless local area networks (WLANs) have been growing exponen... more Installations of IEEE 802.11-based wireless local area networks (WLANs) have been growing exponentially over the past two years due to their low cost and high-speed data rate capabilities. Although many organizations have started using WLANs, there are still few tools available that assist in the design of WLAN networks. As a result, the current deployment of WLAN networks remains ad-hoc in nature. The objective of the research reported here is to develop modeling tools for performance optimization of WLAN networks. In particular, we attempt to develop propagation models that can predict the signal strength and interference in a WLAN system by taking environment specific parameters into account such as the structure of the building, presence or absence of stationary obstacles, etc (COST231 Final Report, 1998). This paper investigates the influence of moving obstacles, such as people, on radio wave propagation inside a building and the effect on received signal quality, in particular the bit error rate in an IEEE802.11 2.4 GHz channel. Our findings suggest that the presence of moving obstacles, such as people, causes strong variations in the received signal, which seriously affects the quality of the received signal.
The accelerometers integrated in today's phones can be used to estimate the distance travelled fr... more The accelerometers integrated in today's phones can be used to estimate the distance travelled from the accelerations made while walking. The placement of the sensor on the body is important to take into consideration. In this paper, the accelerations recorded with a daily-used phone in the trouser pocket were processed on a mobile device to detect steps and estimate the distance travelled. The outcome of the distance estimates shows an error of 0.05 metres per one metre and can be improved through calibration. This distance was applied in the motion model of a particle filter, and fused with a map of the building. The results establish that the estimates of the algorithm are valuable when fusing with other technologies or environment information, to aid the estimation of the location.
IEEE Transactions on Evolutionary Computation, 2011
The complex nature of wireless local area networks (WLAN) design has led many of the deployments ... more The complex nature of wireless local area networks (WLAN) design has led many of the deployments being done in an ad-hoc fashion without efficient design methodologies. Although this approach may work for a small environment with a small number of access points, it is infeasible to use such a process when designing a larger wireless infrastructure. Due to the low cost that is indicative of WLAN deployments, many practitioners view formal optimization techniques as being too complex and costly to implement. There have been a number of research works that investigate the use of formal optimization techniques for the accurate design of a WLAN. Unfortunately, the approaches taken do not address one major issue when designing a complex and demanding wireless network infrastructure, namely scalability. An optimization algorithm must consider a multitude of design criteria and therefore needs to be scalable to be successfully applied to large scenarios. The main contribution of the work presented in this paper is the development of a scalable optimization algorithm based on the tools of distributed artificial intelligence, which overcomes the failings of current approaches and can be utilized for WLAN design regardless of size or complexity of site specific requirements.
There is an increasing demand for efficient and accurate indoor signal propagation prediction too... more There is an increasing demand for efficient and accurate indoor signal propagation prediction tools. A novel semi-deterministic approach based on a simple ray launching technique, the Monte Carlo method, and general statistics is developed. Without complicated calculations, all the electromagnetic issues, including diffuse scattering, are taken into account in the prediction using a new "motif concept". The motif model based on this approach is developed, implemented and tested. The signal strength as well as wide-band parameters can be predicted at very high speed. Software implementation of the model and first evaluations prove good performance and accuracy. A three-dimensional enhancement of the model is proposed
Page 1. Rao-Blackwellized Particle Filter for Pattern Matching Indoor Localisation Sigit Basuki W... more Page 1. Rao-Blackwellized Particle Filter for Pattern Matching Indoor Localisation Sigit Basuki Wibowo, Martin Klepal NIMBUS Centre for Embedded Systems Research Cork Institute of Technology Cork, Ireland Email: {sigit.wibowo, martin.klepal}@cit.ie ...
For professional users such as firefighters and other first responders, GNSS positioning technolo... more For professional users such as firefighters and other first responders, GNSS positioning technology (GPS, assisted GPS) can satisfy outdoor positioning requirements in many instances. However, there is still a need for high-performance deep indoor positioning for use by these same professional users. This need has already been clearly expressed by various communities of end users in the context of WearIT@Work, an R&D project funded by the European Community's Sixth Framework Program. It is known that map matching can help for indoor pedestrian navigation. In most previous research, it was assumed that detailed building plans are available. However, in many emergency / rescue scenarios, only very limited building plan information may be at hand. For example a building outline might be obtained from aerial photographs or cataster databases. Alternatively, an escape plan posted at the entrances to many building would yield only approximate exit door and stairwell locations as well as hallway and room orientation. What is not known is how much map information is really required for a USAR mission and how much each level of map detail might help to improve positioning accuracy. Obviously, the geometry of the building and the course through will be factors consider. The purpose of this paper is to show how a previously published Backtracking Particle Filter (BPF) can be combined with different levels of building plan detail to improve PDR performance. A new in/out scenario that might be typical of a reconnaissance mission during a fire in a two-story office building was evaluated. Using only external wall information, the new scenario yields positioning performance (2.56 m mean 2D error) that is greatly superior to the PDR-only, no map base case (7.74 m mean 2D error). This result has a substantial practical significance since this level of building plan detail could be quickly and easily generated in many emergency instances. The technique could be used to mitigate- - heading errors that result from exposing the IMU to extreme operating conditions. It is hoped that this mitigating effect will also occur for more irregular paths and in larger traversed spaces such as parking garages and warehouses.
Installations of IEEE 802.11-based wireless local area networks (WLANs) have been growing exponen... more Installations of IEEE 802.11-based wireless local area networks (WLANs) have been growing exponentially over the past two years due to their low cost and high-speed data rate capabilities. Although many organizations have started using WLANs, there are still few tools available that assist in the design of WLAN networks. As a result, the current deployment of WLAN networks remains ad-hoc in nature. The objective of the research reported here is to develop modeling tools for performance optimization of WLAN networks. In particular, we attempt to develop propagation models that can predict the signal strength and interference in a WLAN system by taking environment specific parameters into account such as the structure of the building, presence or absence of stationary obstacles, etc (COST231 Final Report, 1998). This paper investigates the influence of moving obstacles, such as people, on radio wave propagation inside a building and the effect on received signal quality, in particular the bit error rate in an IEEE802.11 2.4 GHz channel. Our findings suggest that the presence of moving obstacles, such as people, causes strong variations in the received signal, which seriously affects the quality of the received signal.
The accelerometers integrated in today's phones can be used to estimate the distance travelled fr... more The accelerometers integrated in today's phones can be used to estimate the distance travelled from the accelerations made while walking. The placement of the sensor on the body is important to take into consideration. In this paper, the accelerations recorded with a daily-used phone in the trouser pocket were processed on a mobile device to detect steps and estimate the distance travelled. The outcome of the distance estimates shows an error of 0.05 metres per one metre and can be improved through calibration. This distance was applied in the motion model of a particle filter, and fused with a map of the building. The results establish that the estimates of the algorithm are valuable when fusing with other technologies or environment information, to aid the estimation of the location.
IEEE Transactions on Evolutionary Computation, 2011
The complex nature of wireless local area networks (WLAN) design has led many of the deployments ... more The complex nature of wireless local area networks (WLAN) design has led many of the deployments being done in an ad-hoc fashion without efficient design methodologies. Although this approach may work for a small environment with a small number of access points, it is infeasible to use such a process when designing a larger wireless infrastructure. Due to the low cost that is indicative of WLAN deployments, many practitioners view formal optimization techniques as being too complex and costly to implement. There have been a number of research works that investigate the use of formal optimization techniques for the accurate design of a WLAN. Unfortunately, the approaches taken do not address one major issue when designing a complex and demanding wireless network infrastructure, namely scalability. An optimization algorithm must consider a multitude of design criteria and therefore needs to be scalable to be successfully applied to large scenarios. The main contribution of the work presented in this paper is the development of a scalable optimization algorithm based on the tools of distributed artificial intelligence, which overcomes the failings of current approaches and can be utilized for WLAN design regardless of size or complexity of site specific requirements.
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Papers by Martin Klepal