Thales (Netherlands)

About: Thales (Netherlands) is a company organization based out in Hengelo, Netherlands. It is known for research contribution in the topics: Electromagnetic compatibility & Radar. The organization has 40 authors who have published 52 publications receiving 518 citations. The organization is also known as: Hollandse Signaalapparaten B.V. & Signaal.

Measuring, Logging, and Visualizing Pulsed Electromagnetic Fields Combined with GPS Location Information

Abstract: Diode detectors and thermocouple detectors are the standard sensors for measuring electromagnetic fields. Thermocouple detectors are most suitable for detecting average values of pulsed signals. In case of peak detection of the field strength, the thermocouple detector is too slow and diode detectors have to be used. In case of a large crest factor, e.g. with a radar, a cascaded diode detector is needed, which is not available as a standard exposure electromagnetic field strength probe. Furthermore, a continuous registration of location while doing measurements is added. This paper describes a data acquisition (DAQ) system built in LabView(lv), which displays and logs the data of a cascaded diode-based wideband power sensor and a GPS sensor in a synchronized way. The LV program also displays the power sensor parameters and the associated GPS location in a heads up display (HUD) using the Microsoft HoloLens. This allows the user to walk and see the measured data in augmented reality without the need to look down on a laptop and missing the maximum measured electric field strength. This reduction in delay occurring from human reaction time allows to follow measurements more accurately in real time. The built system is convenient, compact and mobile in usage and can be used for compliance testing with the health and safety requirements for workers or the general public of radiated electrical fields in difficult to reach areas without compromising safety regulations.

Towards decisive garments for heat stress risk detection

Abstract: One of the numerous applications of wearable computers is providing safety in occupations where heat-related injuries are prevalent. Core temperature, as a parameter that cannot be measured by on-body sensors is a variable that is specifically interesting for realizing such applications. In the context of the design of a sensor-shirt that can be used by firefighters, in this paper we study the importance of different types of sensor measurements and their placement for estimating core temperature. We propose a model for inferring the dangerous states of core temperature. Our evaluation results show that our model can to a great extent estimate hazardous situations caused by heat accumulation.

Evolution of naval AESA radars

Abstract: Modern radar development is driven by an evolving and expanding range of threats. The low end of the threat spectrum is composed of small, slow-moving targets such as UAVs or small surface vessels. At the high end of the threat spectrum there is an increasing number of very fast missiles, up to the level of (Tactical) Ballistic Missiles. Furthermore, the mission environment has evolved as well, which is illustrated on the naval side by increased operations in littoral environments, often in an asymmetric warfare setting. Active Electronically Scanned Array (AESA) radar systems are uniquely suited to operate in these operational and threat environments, where the flexibility and redundancy of AESA systems give them an edge over more conventional solutions. Active array systems have been in use for more than a decade now (e.g., the APAR X-band system). Typically, these systems use RF beamforming or 1D Digital Beamforming (DBF). Recent advances in technology have made it possible to extend these beamforming concepts to full 2D digital beamforming, also known as Dual Axis Multi-beam. This results in additional flexibility and possibilities on a system level. This paper describes the underlying technology evolution and the added functionality and flexibility that is achieved with such systems.

Estimation of the probability distributions for cable coupling using unscented transforms

Abstract: This work presents the use of unscented transforms (UT) for the description of statistical uncertainty in electromagnetic coupling between cables. UT greatly reduce the computational burden for the statistical analysis of nonlinear problems compared with more traditional approaches such as the Monte Carlo technique. Coupling between cables has a nonlinear parameter dependence and has a high variability due to the variability in the cable braid manufacture and the highly variable nature of cable layout. Therefore, cable coupling can only be defined within statistical limits. First, it is shown that by analyzing the resonances the important features of maximum coupling and the point of maximum coupling can be characterized. It is then demonstrated how UT can be used to efficiently identify the parameters which contribute significantly to the uncertainty in cable coupling and then to provide a measure of the probability distribution for the multivariate problem.

Dual axis multi-beam radars

Abstract: The evolution in today's radar design is driven by new and highly variable naval and land-based missions encountering a great diversity of threats. The broad threat spectrum ranges from small slow moving UAVs to very small, fast and agile missiles. Detecting these targets simultaneously imposes conflicting requirements on a radar design. The great variety of missions in an increasingly complex littoral environment requires a flexible radar design with multi-mission capabilities. The system also needs to be easy upgradable, supporting modernization of the system during its operational lifetime to enable adaptation to new threats. New technologies, such as the introduction of Active Electronically Scanned Array (AESA) antenna technology, compact receiver technology and growth in processing power opens the door to the introduction of Dual Axis Multi-beam forming. By inserting this next step in digital beam forming, the great variety and often conflicting requirements imposed on a modern radar system can be dealt with, without the need for the operator to switch between multiple modes. This paper will describe the working and benefits of Dual Axis Multi-beam forming, as well as the operational advantages. The concepts are applicable for fixed and rotating antenna radars.