Table 2 - uploaded by Krzysztof Herman
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The work presents the results of experimental study on the possibilities of determining the source of an ultrasonic signal in two-dimensional space (distance, horizontal angle). During the research the team used a self-constructed linear array of MEMS microphones. Knowledge in the field of sonar systems was utilized to analyse and design a location...
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Citations
... This type of sonar appeared to be very effective and made it possible to implement the system BatSLAM which was able to solve the simultaneous localization and mapping problem (SLAM) (Steckel, Peremans, 2015). MEMS microphones were also used in (Herman et al., 2014) to create a linear array. The DOA was determined by implementing of beamforming algorithms. ...
The paper presents and discusses a method of azimuth determination of ultrasonic echo arrival in air. The basis of the presented approach is the assumption that the received signal is a narrowband one. In this way, the direction of the signal arrival can be determined based on its phase shift using two receivers. When the distance between the receivers exceeds half of the wavelength of the received signal, a problem of ambiguity in determining the angle of arrival arises. To solve this, a method using multiple pairs of receivers was used. Its robustness and temperature dependence is analysed. The most important advantages of the presented approach are simplified computations and low hardware requirements. Experimental data made it possible to show that for strong echoes, the accuracy is higher than 0.5 degree. In the case of weak echos, it is reduced to about 2 degrees. Because the method is based on phase shift measurement, the ultrasonic sonar that uses this method can be compact in size. Moreover, owing to the theoretical analysis, certain properties of the mutual location of the receivers were found and formally proved. They are crucial for determining proper receivers' inter-distances.
... In [1], it is measured by comparing phase of signals received by five transducers arranged in a cruciform. The application of a linear array of MEMS microphones for DOA determination is presented in [2]. It was used for the implementation of beamforming algorithms and correlation function-based methods. ...
The paper presents a method which makes it possible to determine in air the azimuth of ultrasonic echo arrival using popular piezoelectric ultrasonic receivers. Experimental data made it possible to show that the accuracy is better than 1 degree in the range about 60 degrees. This feature allowed the reliability of measurement data interpretation to be radically improved.
... MEMS technology made it possible to create small size microphones. In [5], a linear array of MEMS microphones is presented. It was used for the implementation of beamforming algorithms and correlation function-based methods. ...
In the paper, an idea of a method of signal arrival direction estimation is presented. The influence of time error measurements on the usage of the method is described. An approach to the problem of an increase in the robustness of the method is proposed. The results of experiments are presented and discussed. © 2017, Industrial Research Institute for Automation and Measurements. All rights reserved.
... Such approaches were proposed in [1], [2]. Other approaches exploits spatial filters [3], [4]. Some researches use a neural network [5] to solve the problem. ...
... MEMS technology made it possible to create small size microphones. In [4], a linear array of MEMS microphones is presented. It was used to implement beamforming algorithms and correlation functions methods. ...
The problem of incident angle determination for an ultrasonic signal is the main concern of this paper. The problem is considered for a 2-D case when the azimuth angle of echo arrival direction has to be established. Information of that direction is essential for the improvement of data reliability obtained from an ultrasonic range finder. It provides an opportunity for many applications, not only in robotics for obstacle detection, but also in many other areas, e.g., gesture recognition. To determine an incident angle, an approach based on indirect determination of the echo phase shift is presented and discussed. An error analysis is presented and it is shown how a measurement error of signal arrival affects an application of that method. Some preliminary results are presented at the end.
