| 1. |
- Hamid, Mohamed, 1983-, et al.
(författare)
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Multi-Interference Detection Algorithm using Discriminant Analysis in Industrial Environments
- 2013
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Ingår i: 39th Annual Conference of the IEEE Industrial Electronics Society (IECON 2013). - New York : IEEE conference proceedings. - 9781479902248 ; , s. 5600-5604
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Konferensbidrag (refereegranskat)abstract
- In this paper a technique to detect multiple impulsive interference in an industrial environment is proposed and evaluated. The technique is based on discriminant analysis which iteratively peels-off the impulsive interferences. The probability of detection of the technique is tested with and without the iterative peeling-off part. The simulations show that the SIR can be improved by applying the detection technique and then blank or clip the impulsive interference components. The improvement in the SIR depends on the impulsive interference parameters and it can reach up to 17 dB.
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| 2. |
- Ferrer Coll, Javier, 1983-
(författare)
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Channel Characterization and WirelessCommunication Performance in Industrial Environments
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The demand for wireless communication systems in industry has grown in recent years. Industrial wireless communications open up a number of new possibilities for highly flexible and efficient automation solutions. However, a good part of the industry refuses to deploy wireless solutions products due to the high reliability requirements in industrial communications that are not achieved by actual wireless systems. Industrial environments have particular characteristics that differ from typical indoor environments such as office or residential environments. The metallic structure and building dimensions result in time dispersion in the received signal. Moreover, electrical motors, vehicles and repair work are sources of electromagnetic interference (EMI) that have direct implications on the performance of wireless communication links. These degradations can reduce the reliability of communications, increasingthe risk of material and personal incidents. Characterizing the sources of degradations in different industrial environments and improving the performance of wireless communication systems by implementing spatial diversity and EMI mitigation techniques are the main goals of this thesis work.Industrial environments are generally considered to be environments with a significant number of metallic elements and EMI sources. However, with the penetration of wireless communication in industrial environments, we realize that not all industrial environments follow this rule of thumb. In fact, we find a wide range of industrial environments with diverse propagation characteristics and degradation sources. To improve the reliability of wireless communication systems in industrial environments, proper radio channel characterization is needed for each environment. This thesis explores a variety of industrial environments and attempts to characterize the sources of degradation by extracting representative channel parameters such as time dispersion, path loss and electromagnetic interference. The result of this characterization provides an industrial environment classification with respect to time dispersion and EMI levels, showing the diverse behavior of propagation channels in industry.The performance of wireless systems in industrial environments can be improved by introducing diversity in the received signal. This can be accomplished by exploiting the spatial diversity offered when multiple antennas are employed at the transmitter with the possibility of using one or more antennas at the receiver. For maximum diversity gain, a proper separation between the different antennas is needed. However, this separation could be a limiting factor in industrial environments with confined spaces. This thesis investigates the implication of antenna separation on system performance and discusses the benefits of spatial diversity in industrial environments with high time dispersion conditions where multiple antennas with short antenna separations can be employed.To ensure reliable wireless communication in industrial environments, all types of electromagnetic interference should be mitigated. The mitigation of EMI requires interference detection and subsequent interference suppression.This thesis looks at impulsive noise detection and suppression techniques for orthogonal frequency division multiplexing (OFDM) based on wide-band communication systems in AWGN and multi-path fading channels. For this,a receiver structure with cooperative detection and suppression blocks is proposed.This thesis also investigates the performance of the proposed receiver structure for diverse statistical properties of the transmitted signal and electromagnetic interference.
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| 3. |
- Ferrer Coll, Javier, 1983-, et al.
(författare)
-
Characterization of Electromagnetic Properties in Iron-Mine Production Tunnels
- 2012
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Ingår i: Electronics Letters. - : Institution of Engineering and Technology. - 0013-5194 .- 1350-911X. ; 48:2, s. 62-63
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Tidskriftsartikel (refereegranskat)abstract
- Modern underground mines require reliable wireless communication for transmitting voice data, operating surveillance cameras, and monitoring mining equipment such as heavy vehicles. The electromagnetic characteristics of mines therefore have to be considered when determining the type of wireless technology for such critical applications. In this reported work, measurements of radio interference levels, path loss, and multipath propagation are performed in the world's now largest iron ore mine, situated in Sweden, to determine a suitable wireless technology for this mine.
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| 4. |
- Ferrer Coll, Javier, 1983-, et al.
(författare)
-
Industrial Environment Characterization for Future M2M Applications
- 2011
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Ingår i: Proc. 2011 IEEE International Symposium on Electromagnetic Compatibility. - New York : IEEE conference proceedings. - 9781457708107 ; , s. 960-963
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Konferensbidrag (refereegranskat)abstract
- Combining electronics, telecommunications, and information technology to connect devices and remote systems is perhaps the best feature of the future Machine-to-Machine (M2M) technology. Wireless communication technologies for managing future M2M applications are becoming mature, but electromagnetic interference and time dispersion in industrial environments can limit the successful functioning of these wireless systems, leading to a failure in the control of critical functions. The characterization of these environments is necessary for collecting and specifying M2M requirements. In this paper, we present the conclusions from measurements carried out in four different industrial environments during the past three years.
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| 5. |
- Ferrer Coll, Javier, 1983-, et al.
(författare)
-
Industrial Indoor Environment Characterization : Propagation Models
- 2011
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Ingår i: Proceedings of 10th International Symposium on Electromagnetic Compatibility, EMC Europe 2011. - : IEEE. - 9780954114633 ; , s. 245-249
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Konferensbidrag (refereegranskat)abstract
- Results of three years' field measurements on radio propagation in industrial environments have been analyzed using four propagation models: the Saleh-Valenzuela model, the two-cluster model, the indoor power delay profile model, and our more recent adjusted model. In this study, we used the results of measurements performed at a steel mill, a paper mill, and in a laboratory environment for three frequency bands (183-683 MHz, 1640-2140 MHz, and 2200-2700 MHz) and for line-of-sight and non-line-of-sight cases.
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| 6. |
- Ferrer Coll, Javier, 1983-, et al.
(författare)
-
Radio-Frequency Electromagnetic Characterization in Factory Automation Infrastructures
- 2012
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Ingår i: IEEE transactions on electromagnetic compatibility (Print). - 0018-9375 .- 1558-187X. ; 54:3, s. 708-711
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, industrial wireless applications have emerged rapidly. The use of short-range radio communication systems in factories increases the flexibility in industrial processes by reducing the use of cables. However, the technological challenges involved in wireless communication in industrial environments are not trivial; they result in disadvantages with respect to reliability and security because of electromagnetic interferences. To gain an understanding of the performance limits of these wireless applications, knowing the characteristics of these environments is essential. In this approach, amplitude probability distribution (APD) and rms delay spread measurements have been used to perform electromagnetic site surveys in three factory automation infrastructures.
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| 7. |
- Ferrer Coll, Javier, 1983-
(författare)
-
RF Channel Characterization in Industrial, Hospital and Home Environments
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The rapid development of electronic components has resulted in the emergence of newmobile applications targeted at industry and hospital sectors. Moreover, a lack of availablewireless frequencies as result of the growth of wireless systems is becoming a problem.In this thesis we characterize industrial and hospital environments in order to provide theknowledge necessary to asses present and future development of critical wireless applications.Furthermore, we investigate the possibility of using TV white space by analysingthe interference from secondary to primary user in home environments.Some of the wireless solutions used in industries and hospitals come directly fromsystems designed for home or office, such asWLAN and Bluetooth. These systems are notprepared to handle problems associated with interference of impulsive character found inindustrial processes and electrical systems.Typically, industrial environments have been classified as reflective environments dueto the metallic structure present in the buildings. In this thesis, we demonstrate that althoughthis may be generally true, some locations in the industry may have special propertieswith wave propagation characteristics in the opposite direction. Stored materials canabsorb wireless signals, resulting in a coverage problem. From the measurement campaignwe are able to distinguish three main classes of indoor environments (highly reflective,medium reflective and low reflective) with different propagation characteristics.Improving spectrum efficiency can be a solution to the growing demand for wirelessservices and can increase a system’s robustness against interference, particularly in criticalapplications in industrial and hospital environments. One improvement in spectrum efficiencycan be for secondary consumers to reuse unassigned portions of the TV spectrum ata specific time and geographical location. This thesis studies the effect of inserting whitespace devices in the TV broadcast spectrum. Note that any new model must state the maximumpower allocated to secondary users to avoid harmful interference with the primarysignal.The content of this thesis is divided into three parts. The first part is the most comprehensiveand addresses electromagnetic interference and multipath characterization ofindustrial environments. In this part, we have developed a method for channel characterizationfor complex electromagnetic environments and have produced results from differentindustrial environments. The second part presents a preliminary study that characterizesthe electromagnetic interference in a hospital environment. The third part is a study ofsecondary users reusing the TV white spaces.
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| 8. |
- Ferrer Coll, Javier, 1983-, et al.
(författare)
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Statistical Characterization of the Electromagnetic Environment in a Hospital
- 2010
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Ingår i: 2010 Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC). - 9781424456215 ; , s. 289-292
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Konferensbidrag (refereegranskat)abstract
- Thanks to advances in digital technology many hospitals are becoming populated with wireless medical applications to control life critical functions. Electromagnetic interference can cause severe performance degradations on these wireless applications. Several accidents have been reported which calls for a more thorough characterization of these interferences in areas where critical wireless applications are used. In this paper the results of electromagnetic interference measurements performed in a hospital are presented. The amplitude probability distribution (APD) and the inter arrival pulse probability distribution (PSD) are used to characterize these environments. In addition, Middleton parameters can be calculated from the measured data. This study is considered to be a first effort to characterize the 20 MHz -2500 MHz band in hospitals.
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| 9. |
- Ferrer Coll, Javier, 1983-, et al.
(författare)
-
Ultra-Wideband Propagation Channel-Measurements and Simulations in Industrial Environments
- 2010
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Ingår i: 9th International Symposium on EMC joint with 20th International Wroclaw Symposium on EMC. - 9788374934268 ; , s. 615-618
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Konferensbidrag (refereegranskat)abstract
- The coverage area and reliability of wireless applications in industrial environments can be limited by electromagnetic interference and other noise. The use of ultrawideband (UWB) communication systems can be effective in these environments because it affords advantages such as multiple access, lack of significant multipath fading and potentially easier penetrability through various materials. The characterization of the signal propagation mechanism of UWB channels is important from the viewpoint of radio systems design and system performance analysis. In this paper, the results of UWB measurements and simulations in line-of-sight (LOS) and non-line-of-sight (NLOS) industrial multipath environments for three frequency bands are presented.
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| 10. |
- Karlsson, Carl, et al.
(författare)
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Outdoor electromagnetic interference measurements in industrial environments
- 2009
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Ingår i: AMTA 2009.
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Konferensbidrag (refereegranskat)abstract
- The performance of wireless applications in outdoor industrial environments is degraded by the effect of unknown interferences. Therefore, characterization of these environments has to be done. Measurements have been performed to determine electromagnetic interference in three outdoor industrial environments: steel mill, freight train marshalling yard and paper plant. In this paper it is shown how the measurements of the Amplitude Probability Distribution (APD) can be combined with conventional electric field measurements for such characterization in order to determine the interference impact on digital wireless systems.
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