| 1. |
- Ferrer-Coll, Javier, et al.
(author)
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Analysis of wireless communications in underground tunnels for industrial use
- 2012
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In: IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society. - New York : IEEE conference proceedings. - 9781467324212 - 9781467324199 ; , s. 3216-3220
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Conference paper (peer-reviewed)abstract
- Wireless communication is expected to improve the safety and the productivity in underground tunnels for industrial use. However the multiple shapes and structures of tunnels affect wireless communication characteristics in terms of signal propagation which is significantly different from terrestrial environments. This paper presents comprehensive broadband measurements and simulations of multipath propagation and path loss in two underground environments. The results can be used in the development of new communication systems in tunnels that provide industrial services.
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| 2. |
- Ferrer-Coll, Javier, et al.
(author)
-
Antenna Cross Correlation and Ricean -Factor Measurements in Indoor Industrial Environments at 433 and 868 MHz
- 2013
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In: Wireless personal communications. - : Springer Science and Business Media LLC. - 0929-6212 .- 1572-834X. ; 73:3, s. 587-593
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Journal article (peer-reviewed)abstract
- The Ricean K-factor and antenna diversity properties for indoor industrial environments have been characterized for 433 and 868 MHz. The high amount of metallic structures gives a multipath environment that heavily differs from other environments e.g. indoor office environments. The results show that low correlation between receiving antennas can be achieved for shorter antenna distances than in other environments.
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| 3. |
- Ferrer Coll, Javier, 1983-, et al.
(author)
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Characterization of Electromagnetic Properties in Iron-Mine Production Tunnels
- 2012
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In: Electronics Letters. - : Institution of Engineering and Technology. - 0013-5194 .- 1350-911X. ; 48:2, s. 62-63
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Journal article (peer-reviewed)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, et al.
(author)
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Detection and Suppression of Impulsive Noise in OFDM Receiver
- 2015
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In: Wireless personal communications. - : Springer-Verlag New York. - 0929-6212 .- 1572-834X.
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Journal article (peer-reviewed)abstract
- In recent years, the use of wireless systems in industrial applications has experienced spectacular growth. Unfortunately, industrial environments often present impulsive noise which degrades the reliability of wireless systems. OFDM is an enhanced technology used in industrial communication to monitor the work and movement of employees using high quality video. However, OFDM is sensitive to high amplitude impulsive noise because the noise energy spreads among all OFDM sub-carriers. This paper proposes a receiver structure consisting of two stages: a detector stage combining Fisher’s Quadratic discriminant and Gaussian Hypothesis techniques, and a suppression stage optimized by setting well defined thresholds. The receiver structure has been tested by simulations and measurements providing an increment in the probability of detection and improving the system performance.
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| 5. |
- Stenumgaard, Peter, et al.
(author)
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Challenges and conditions for wireless machine-to-machine communications in industrial environments
- 2013
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In: IEEE Communications Magazine. - : IEEE. - 0163-6804 .- 1558-1896. ; 51:6, s. 187-192
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Journal article (peer-reviewed)abstract
- Wireless solutions are rapidly growing in machine-to-machine communications in industrial environments. These environments provide challenging conditions in terms of radio wave propagation as well as electromagnetic interference. In this article, results from the characterization of radio channel properties are summarized in order to provide some guidelines for the choice of wireless solutions in industrial environments. In conclusion, it is essential to know the sensitivity of industrial processes to time delay in data transfer. Furthermore, it is important to be aware of the radio interference environment and the manner in which different wireless technologies react upon interference. These steps will minimize the risk of unforeseen expensive disturbances in industrial processes.
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| 6. |
- Ferrer-Coll, Javier, et al.
(author)
-
Impulsive Noise Detec-tion in OFDM Systems with PAPR Reduction
- 2014
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In: 2014 International symposium on electromagnetic compatibility (EMC Europe). - : IEEE conference proceedings. - 9781479932269 ; , s. 523-527
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Conference paper (other academic/artistic)abstract
- Impulsive noise is a major source of degradation in industrial communications. Orthogonal frequency-division multiplexing (OFDM) is an extended technique used in many industrial communications, however the performance of OFDM systems is reduced under an impulsive noise source. To increase the system performance, impulsive noise detection and suppression techniques can be designed in the communication system. OFDM has high levels of peak-to-average power ratio (PAPR), thus PAPR reduction techniques, such as selected mapping (SLM), are implemented in OFDM systems. This paper proposes an impulsive noise detection exploiting the statistical properties of the OFDM envelope when applying SLM. The proposed detection technique increases the probability of detection and improves the BER of the communication system compared to other impulsive detection techniques.
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| 7. |
- Ferrer Coll, Javier, 1983-, et al.
(author)
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Industrial Environment Characterization for Future M2M Applications
- 2011
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In: Proc. 2011 IEEE International Symposium on Electromagnetic Compatibility. - New York : IEEE conference proceedings. - 9781457708107 ; , s. 960-963
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Conference paper (peer-reviewed)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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| 8. |
- Ferrer Coll, Javier, 1983-, et al.
(author)
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Industrial Indoor Environment Characterization : Propagation Models
- 2011
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In: Proceedings of 10th International Symposium on Electromagnetic Compatibility, EMC Europe 2011. - : IEEE. - 9780954114633 ; , s. 245-249
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Conference paper (peer-reviewed)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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| 9. |
- Ferrer Coll, Javier, 1983-
(author)
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RF Channel Characterization in Industrial, Hospital and Home Environments
- 2012
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Licentiate thesis (other academic/artistic)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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| 10. |
- Ferrer Coll, Javier, et al.
(author)
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Simulation and Measurement of Electromagnetic Radiation Absorption in a Finished-product Warehouse
- 2010
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In: IEEE International Symposium on Electromagnetic Compatibility. - 9781424463053 ; , s. 881-884
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Conference paper (peer-reviewed)abstract
- Several studies have characterized industrial environments as being highly reflective. In this paper, we provide the data obtained from electromagnetic field measurements performed at the warehouse of a paper mill. The data is also compared to simulated data. This data proves the existence of non-reflective and very high absorption industrial environments where wireless communication is impossible at certain frequencies. Furthermore, in such environment, radio performance cannot be improved by multiple antenna solutions such as MIMO (Multiple Input Multiple Output) since multiple reflections are effectively absorbed.
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