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Author

Carlos De Marziani

Other affiliations: University of Alcalá
Bio: Carlos De Marziani is an academic researcher from National University of Patagonia San Juan Bosco. The author has contributed to research in topics: Local positioning system & Ultrasonic sensor. The author has an hindex of 10, co-authored 38 publications receiving 290 citations. Previous affiliations of Carlos De Marziani include University of Alcalá.

Papers
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Journal ArticleDOI
TL;DR: The combined use of diverse techniques of data fusion, based on fuzzy logic and the Dempster-Shafer theory of evidence, are proposed, to validate the existence of objects, providing a highly reliable detection system.
Abstract: On current railway systems, it is becoming ever more necessary to install safety elements to avoid accidents. One of the causes that can provoke serious accidents is the existence of obstacles on the tracks, either fixed or mobile. In this paper, a multisensory system that can inform the monitoring system about the existence of obstacles is proposed. The system for obstacle detection consists of two emitting and receiving barriers, which are placed on opposing sides of the railway, respectively, and use infrared and ultrasonic sensors, thus establishing different optical and acoustic links between them. The interruption of one or several links should produce an alarm. However, even without the existence of objects, degradation of links could occur due to atmospheric attenuation, solar radiation, etc., also producing an activation of the alarm system. Since detection is based on the lack of radiation in the detectors, the use of complementary sensors for the same task is justified. Since the minimum size of an object for which an alarm is required to be generated is 50 × 50 × 50 cm, in some situations, several links are interrupted; however, alarms should not be generated. Typical cases are the flight of leaves or the movement of small animals in the scanned area. To avoid alarm activation in such situations, this paper proposes the combined use of diverse techniques of data fusion, based on fuzzy logic and the Dempster-Shafer theory of evidence, to validate the existence of objects, providing a highly reliable detection system.

37 citations

Journal ArticleDOI
TL;DR: In this paper, a prototype of an ultrasonic transducer based on electromechanical film (EMFi) is presented, as well as its electronic driving and receiving blocks.
Abstract: A prototype of an ultrasonic transducer based on electromechanical film (EMFi) is presented, as well as its electronic driving and receiving blocks. The electromechanical film provides a wide bandwidth response, showing enough of a level of sensitivity to allow echo-pulse measurement in the most frequency ranges for robotics applications. Emission patterns are obtained, verifying the correspondence between experimental data and the theoretical piston model. Experimental results show that the EMFi-based transducer can be used as a broadband ultrasonic transducer, allowing transmission from 20 to 200 kHz. The wide bandwidth provided by the transducer is a remarkable advantage for sensor systems using encoded ultrasonic signals with wideband modulation schemes, which require considerably more bandwidth than what conventional transducers allow. In this way, main lobes can be discriminated more easily from sidelobes and crosstalk interference can be reduced.

35 citations

Journal ArticleDOI
31 Oct 2011-Sensors
TL;DR: A time-of-flight detection technique in the frequency domain is described for an ultrasonic Local Positioning System (LPS) based on encoded beacons by means of the DS-CDMA technique.
Abstract: In this article, a time-of-flight detection technique in the frequency domain is described for an ultrasonic Local Positioning System (LPS) based on encoded beacons. Beacon transmissions have been synchronized and become simultaneous by means of the DS-CDMA (Direct-Sequence Code Division Multiple Access) technique. Every beacon has been associated to a 255-bit Kasami code. The detection of signal arrival instant at the receiver, from which the distance to each beacon can be obtained, is based on the application of the Generalized Cross-Correlation (GCC), by using the cross-spectral density between the received signal and the sequence to be detected. Prior filtering to enhance the frequency components around the carrier frequency (40 kHz) has improved estimations when obtaining the correlation function maximum, which implies an improvement in distance measurement precision. Positioning has been achieved by using hyperbolic trilateration, based on the Time Differences of Arrival (TDOA) between a reference beacon and the others.

30 citations

Journal ArticleDOI
TL;DR: A novel receiver for a broadband ultrasonic Local Positioning System (LPS) that features high robustness to noise and multiple access capability, and is capable of detecting beacons emissions despite being installed in a fast moving device and it also provides estimation of its velocity.
Abstract: This paper presents the design of a novel receiver for a broadband ultrasonic Local Positioning System (LPS). As in other devices based on matched filtering of the transmitted encoded signals, this receiver features high robustness to noise and multiple access capability. Unlike previous solutions, the proposed receiver is capable of detecting beacons emissions despite being installed in a fast moving device, and it also provides estimation of its velocity. The system has been implemented in an FPGA-based architecture. An experimental analysis of performance has been carried out. Firstly using a set of test signals synthetically generated to simulate different positions and velocities of the receiver. Secondly, a set of real signals obtained with a prototype have been used. The simulated results show the capability of the system to detect the encoded signals emitted by the LPS infrastructure when the device is moving at velocities of up to 3 m/s under low SNR conditions. The real results confirm the improved system capability, but also make evident the negative influence that phenomena such as the transducers response and multipath propagation can have on system performance.

27 citations

Journal ArticleDOI
TL;DR: An organization and operation algorithm is proposed, which provides a temporal reference to the acoustic emissions carried out by every node, thus reducing hardware complexity, power consumptions, and possible interferences with other systems.
Abstract: In relative positioning systems, with the aim of estimating object positions, distances among them are computed in a cooperative way, usually by measuring times-of-flight from the signals that they emit. These emissions are often synchronized with additional signals or suitable hardware that acts as a temporal reference. In this paper, a ranging system is presented where only acoustic emissions are used to compute the distances between objects or nodes. Thus, an organization and operation algorithm is proposed, which provides a temporal reference to the acoustic emissions carried out by every node. In this way, distances are computed by determining the temporal relation between a request of emission from a coordinator node and the corresponding answers emitted by the other nodes. In order to simultaneously detect the acoustic emissions, the signals are encoded with complementary set of sequences allowing multisensory operation and accepting low signal-to-noise conditions. With this measurement scheme, additional signals and high accuracy clocks often used for synchronization can be eliminated, thus reducing hardware complexity, power consumptions, and possible interferences with other systems (i.e., if radio frequency signals are used). The simulation and experimental results show that sub-centimeter accuracy can be obtained with the proposed ranging scheme.

23 citations


Cited by
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Journal ArticleDOI
TL;DR: A survey on the development of D2ITS is provided, discussing the functionality of its key components and some deployment issues associated with D2 ITS Future research directions for the developed system are presented.
Abstract: For the last two decades, intelligent transportation systems (ITS) have emerged as an efficient way of improving the performance of transportation systems, enhancing travel security, and providing more choices to travelers. A significant change in ITS in recent years is that much more data are collected from a variety of sources and can be processed into various forms for different stakeholders. The availability of a large amount of data can potentially lead to a revolution in ITS development, changing an ITS from a conventional technology-driven system into a more powerful multifunctional data-driven intelligent transportation system (D2ITS) : a system that is vision, multisource, and learning algorithm driven to optimize its performance. Furthermore, D2ITS is trending to become a privacy-aware people-centric more intelligent system. In this paper, we provide a survey on the development of D2ITS, discussing the functionality of its key components and some deployment issues associated with D2ITS Future research directions for the development of D2ITS is also presented.

1,336 citations

Journal ArticleDOI
B.B. Bauer1
01 Apr 1963

897 citations

Journal ArticleDOI
21 Jul 2020-Sensors
TL;DR: This article presents standard methods to match the acoustic impedance of the piezoelectric sensors, actuators, and transducers with the surrounding wave propagation media.
Abstract: The coupling of waves between the piezoelectric generators, detectors, and propagating media is challenging due to mismatch in the acoustic properties. The mismatch leads to the reverberation of waves within the transducer, heating, low signal-to-noise ratio, and signal distortion. Acoustic impedance matching increases the coupling largely. This article presents standard methods to match the acoustic impedance of the piezoelectric sensors, actuators, and transducers with the surrounding wave propagation media. Acoustic matching methods utilizing active and passive materials have been discussed. Special materials such as nanocomposites, metamaterials, and metasurfaces as emerging materials have been presented. Emphasis is placed throughout the article to differentiate the difference between electric and acoustic impedance matching and the relation between the two. Comparison of various techniques is made with the discussion on capabilities, advantages, and disadvantages. Acoustic impedance matching for specific and uncommon applications has also been covered.

97 citations

Journal ArticleDOI
21 Sep 2020-Sensors
TL;DR: This paper identifies the key requirements for achieving essential services as well as common platforms for UWSN and contributes a taxonomy of the critical elements in UWSNs by devising a classification on architectural elements, communications, routing protocol and standards, security, and applications.
Abstract: The domain of underwater wireless sensor networks (UWSNs) had received a lot of attention recently due to its significant advanced capabilities in the ocean surveillance, marine monitoring and application deployment for detecting underwater targets. However, the literature have not compiled the state-of-the-art along its direction to discover the recent advancements which were fuelled by the underwater sensor technologies. Hence, this paper offers the newest analysis on the available evidences by reviewing studies in the past five years on various aspects that support network activities and applications in UWSN environments. This work was motivated by the need for robust and flexible solutions that can satisfy the requirements for the rapid development of the underwater wireless sensor networks. This paper identifies the key requirements for achieving essential services as well as common platforms for UWSN. It also contributes a taxonomy of the critical elements in UWSNs by devising a classification on architectural elements, communications, routing protocol and standards, security, and applications of UWSNs. Finally, the major challenges that remain open are presented as a guide for future research directions.

87 citations

Journal ArticleDOI
31 Mar 2014-Sensors
TL;DR: A review of developments in the use of FPGAs in sensor systems is presented, describing as well the FPGA technologies employed by the different research groups and providing an overview of future research within this field.
Abstract: The current trend in the evolution of sensor systems seeks ways to provide more accuracy and resolution, while at the same time decreasing the size and power consumption. The use of Field Programmable Gate Arrays (FPGAs) provides specific reprogrammable hardware technology that can be properly exploited to obtain a reconfigurable sensor system. This adaptation capability enables the implementation of complex applications using the partial reconfigurability at a very low-power consumption. For highly demanding tasks FPGAs have been favored due to the high efficiency provided by their architectural flexibility (parallelism, on-chip memory, etc.), reconfigurability and superb performance in the development of algorithms. FPGAs have improved the performance of sensor systems and have triggered a clear increase in their use in new fields of application. A new generation of smarter, reconfigurable and lower power consumption sensors is being developed in Spain based on FPGAs. In this paper, a review of these developments is presented, describing as well the FPGA technologies employed by the different research groups and providing an overview of future research within this field.

79 citations