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DOA Estimation of Ultrasonic Signal by Indirect Phase Shift Determination

Kreczmer Bogdan

Archives of Acoustics

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2024

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Vol. 49, nr 1

107--120

EN

The paper presents the concept of the method of determining the direction of ultrasonic signal arrival, i.e., the azimuth and elevation angles. This method is an extension of the previous approach which was proposed to determine only the azimuth angle. The approach is based on the indirect phase determination. This makes it possible to tolerate spacing of receivers greater than half the wavelength of the received signal. At the same time, it provides increased measurement accuracy and reduced hardware requirements. To check the robustness of the method, simulations were carried out for the geometric arrangement of the receivers of the sonar module, for which the method was then implemented. This sonar module was used in the conducted experiments. The results of these simulations and experiments are included in the paper and discussed.

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Wyznaczanie kierunki przylotu sygnału z zastosowaniem metody pośredniej detekcji fazy

Kreczmer Bogdan

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2022

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z. 197, t. 2

51-62

PL

W niniejszym referacie przedstawiono metodę wyznaczania kierunku przylotu sygnału ultradźwiękowego. Omówiony został problem niejednoznacznych rozwiązań w przypadku, gdy odbiorniki są oddalone od siebie bardziej niż o pół długości fali emitowanego sygnału. Przedstawiono sposób rozwiązania tego problemu. Opisano również wpływ geometrii rozmieszczenia odbiorników na błąd wyznaczanie współrzędnych wektora kierunku przylotu sygnału. Przedstawiono ponadto wyniki symulacji, które pozwoliły ocenić odporność układu pomiarowego na błędy pomiaru czasu przelotu i oszacować ich górną akceptowalną wartość.

EN

This paper presents a method of determining the direction of ultrasonic signal arrival. The problem of ambiguous solutions in the case when the receivers are more distant from each other than by half the wavelength of the emitted signal is discussed. The method od solving this problem is presented. The influence of the geometry of the arrangement of receivers on the error in determining the coordinates of the signal arrival direction vector was also described. The simulation results are also presented. They allowed to assess the resistance of the measuring system to errors in time of flight measurement and to estimate their upper acceptable limit.

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System sensoryczny wielomodalnej percepcji otoczenia - koncepcja i analiza przypadków użycia

Kreczmer Bogdan, Arent Krzysztof, Jakubiak Janusz

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2022

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z. 197, t. 2

63-76

PL

Niniejszy referat prezentuje koncepcję multimodalnej percepcji otoczenia opartą na trzech typach sensorów tj. sonarze ultradźwiękowym, uproszczonej kamerze 3D oraz uproszczonej kamerze termowizyjnej. Podstawowym celem takiego wyboru jest otrzymanie układu sensorycznego, który redukuje ilość informacji podlegającej przetworzeniu. Jednocześnie układ ma dostarczyć lokalnie precyzyjnych danych o otoczeniu. Takie podejście umożliwi realizację nawigacji robota mobilnego, zadania SLAM oraz interakcji z ludźmi. Pod kątem przedstawionych założeń dokonano przeglądu wspominanych typów sensorów oraz metod przetwarzania danych. Całość zamknięto podsumowaniem, w którym wskazano konkretne sensory, które mogą stanowić podstawę proponowanego multimodalnego systemu sensorycznego.

EN

This paper presents the concept of multimodal perception of the environment based on three types of sensors, i.e. ultrasonic sonar, simplified 3D camera and simplified thermal imaging camera. The primary purpose of such a choice is to obtain a sensory system that reduces the amount of necessary information to be processed. However, at the same time, it is to ensure the receipt of locally precise data about the environment. This approach is to enable the implementation of mobile robot navigation, SLAM tasks and interactions with people. With this in mind, the above-mentioned types of sensors and data processing methods were reviewed in this respect. The paper is closed with a summary, which indicates specific sensors that can from the basis of the proposed multimodal sensory system.

4

Estimation of the Azimuth Angle of the Arrival Direction for an Ultrasonic Signal by Using Indirect Determination of the Phase Shift

Kreczmer Bogdan

Archives of Acoustics

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2019

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Vol. 44, No. 3

585--601

EN

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 import ant 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°. In the case of weak echos, it is reduced to about 2°. 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.