Publication

Acoustic goniometry

Eric Van Lancker
2002
EPFL thesis
Abstract

This work was motivated by the increasing need for acoustic localization systems. The various localization systems that were implemented during this PhD include localization of snow avalanches, artillery and supersonic aircraft in the infrasound domain, the localization of helicopters, civilian aircraft, speakers and auditorium reflections in the audio domain and the localization of chirps in the underwater ultrasound domain. The "goniometer" is defined as an instrument that measures angles. An "acoustic goniometer" is therefore a system that measures the direction of arrival (DOA) of sounds, and thus estimates the source direction. A goniometer is made up of an antenna, composed of several sensors arranged in a particular geometry, and a calculation algorithm. The successive implementations were designed around a common framework, based on a two-step spatio-temporal process. The temporal step tackles the problem of the Time Delay Estimation along the antenna baselines, whereas the second step introduces the antenna geometry, in order to estimate the Direction of Arrival per se. The multi-sources case, as well as the outlier's rejection, is assured by a detection module, which uses the temporal and spatial properties of the propagation model. The performances of the TDE and the localization are studied as a function of every relevant parameter, in order to determine the optimal antenna to run the two-step process. The antenna design rules concern its geometry, its size and its orientation. The results presented in the applications chapter give a realistic idea of the goniometry capacities. Its performances are largely competitive to those of other techniques. Up to now, the goniometry developed during this work, fulfilled all prior requirements. Moreover, the goniometry appeared to be, in many cases, in advance with regards to technological tools such as the sound pick-up, the CPU implementation or installation constraints. The advice that could be given, when tackling a new antenna design, is firstly to visualize both spatial and temporal properties of the propagating waves and of the perturbating phenomena, and secondly to compare them to the goniometer characteristics. This work has demonstrated that the best performances were achieved for the goniometry of a unique stationary compact source generating broadband low pass signals in a homogenous medium without wind and noise, performed with a wide symmetrical broad-side antenna.

About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related concepts (32)
Dipole antenna
In radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. The dipole is any one of a class of antennas producing a radiation pattern approximating that of an elementary electric dipole with a radiating structure supporting a line current so energized that the current has only one node at each end. A dipole antenna commonly consists of two identical conductive elements such as metal wires or rods.
Antenna (radio)
In radio engineering, an antenna (American English) or aerial (British English) is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver. In transmission, a radio transmitter supplies an electric current to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic waves (radio waves). In reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be amplified.
Antenna array
An antenna array (or array antenna) is a set of multiple connected antennas which work together as a single antenna, to transmit or receive radio waves. The individual antennas (called elements) are usually connected to a single receiver or transmitter by feedlines that feed the power to the elements in a specific phase relationship. The radio waves radiated by each individual antenna combine and superpose, adding together (interfering constructively) to enhance the power radiated in desired directions, and cancelling (interfering destructively) to reduce the power radiated in other directions.
Show more
Related publications (35)

Toward Metantennas: Metamaterial-Based Antennas for Wireless Communications

Yuanyan Su

Antennas have historically been the most common electromagnetic (EM) technology for wireless communication systems. Antenna as hardware is entirely dependent on the EM properties of the materials used, mostly related to the permittivity and permeability. I ...
Piscataway2023

Small antennas with broad beamwidth integrated on a drone enclosed in a protective structure

Anja Skrivervik

In this paper, we analyze the integration of small antennas in a drone protected by a conductive structure. They must be light and resistant to provide high collision resilience, which is critical for drones flown indoors and in complex environments. To ac ...
IEEE2023

Metasurface Near-Field Measurements with Incident Field Reconstruction Using a Single Horn Antenna

Shourya Dutta Gupta, Ville Tuovi Tiukuvaara

Metasurfaces (MSs) are the 2-D equivalent of metaterials, the latter being a class of artificial engineered materials exhibiting peculiar electromagnetic properties [1], [2]. Generally constructed as arrays of deeply sub-wavelength resonant particles on a ...
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022
Show more
Related MOOCs (8)
The Radio Sky II: Observational Radio Astronomy
This course covers the principles and practices of radio astronomical observations, in particular with modern interferometers. Topics range from radio telescope technology to the measurement equation
Plasma Physics: Introduction
Learn the basics of plasma, one of the fundamental states of matter, and the different types of models used to describe it, including fluid and kinetic.
Plasma Physics: Introduction
Learn the basics of plasma, one of the fundamental states of matter, and the different types of models used to describe it, including fluid and kinetic.
Show more