07-07-2012, 11:12 AM
Acoustic wave
[attachment=27056]
Acoustic waves are a type of longitudinal waves that propagate by means of adiabatic compression and decompression. Longitudinal waves are waves that have the same direction of vibration as their direction of travel. Important quantities for describing acoustic waves are sound pressure, particle velocity, particle displacement and sound intensity. Acoustic waves travel with the speed of sound which depends on the medium they're passing through.
Wave properties
Acoustic waves are longitudinal waves that exhibit phenomena like diffraction, reflection and interference. Sound waves however don't have any polarization since they oscillate along the same direction as they move. A New Compact Multichannel Receiver for
Underwater Wireless Communication Networks Ali Abdi, Senior Member, IEEE, and Huaihai Guo
Abstract
In this letter it is shown that by taking advantage of the particle velocity, in addition to the pressure, multichannel reception can be accomplished in underwater acoustic wireless channels. Theoretical formulation and Monte Carlo simulations are provided for a vector sensor equalizer that measures the pressure and the velocity at a single point in space.
. INTRODUCTION
A vector sensor is capable of measuring important non-scalar components of the acoustic field such as the particle velocity, which cannot be obtained by a single scalar pressure sensor. In the past few
decades, extensive research has been conducted on the theory and design of vector sensors (see, for example, [1] and [2]). They have been mainly used for underwater target localization and SONAR
applications. A. Abdi and H. Guo are with the Center for Wireless Communications and Signal Processing Research, Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA. Contact e-mail: ali.abdi[at]njit.edu and hg45[at]njit.edu. 2 On the other hand, underwater acoustic communication systems have used scalar sensors only, which measure the pressure of the acoustic field. The new idea of this paper is to take advantage of the vector components of the acoustic field, such as the particle velocity, sensed by a vector sensor at the receiver, for detecting the transmitted data. This reduces the size of the receiver since a vector sensor measures the scalar and vector components of the acoustic field at a single point in space. In other words, multiple channels in the proposed receiver are co-located. This is different from
conventional multichannel underwater acoustic receivers, which employ spatially separated pressure-only sensors that may result in large arrays. The small size of the proposed receiver makes it particularly useful for small unmanned underwater vehicles and some underwater wireless sensor networks [4].
[attachment=27056]
Acoustic waves are a type of longitudinal waves that propagate by means of adiabatic compression and decompression. Longitudinal waves are waves that have the same direction of vibration as their direction of travel. Important quantities for describing acoustic waves are sound pressure, particle velocity, particle displacement and sound intensity. Acoustic waves travel with the speed of sound which depends on the medium they're passing through.
Wave properties
Acoustic waves are longitudinal waves that exhibit phenomena like diffraction, reflection and interference. Sound waves however don't have any polarization since they oscillate along the same direction as they move. A New Compact Multichannel Receiver for
Underwater Wireless Communication Networks Ali Abdi, Senior Member, IEEE, and Huaihai Guo
Abstract
In this letter it is shown that by taking advantage of the particle velocity, in addition to the pressure, multichannel reception can be accomplished in underwater acoustic wireless channels. Theoretical formulation and Monte Carlo simulations are provided for a vector sensor equalizer that measures the pressure and the velocity at a single point in space.
. INTRODUCTION
A vector sensor is capable of measuring important non-scalar components of the acoustic field such as the particle velocity, which cannot be obtained by a single scalar pressure sensor. In the past few
decades, extensive research has been conducted on the theory and design of vector sensors (see, for example, [1] and [2]). They have been mainly used for underwater target localization and SONAR
applications. A. Abdi and H. Guo are with the Center for Wireless Communications and Signal Processing Research, Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA. Contact e-mail: ali.abdi[at]njit.edu and hg45[at]njit.edu. 2 On the other hand, underwater acoustic communication systems have used scalar sensors only, which measure the pressure of the acoustic field. The new idea of this paper is to take advantage of the vector components of the acoustic field, such as the particle velocity, sensed by a vector sensor at the receiver, for detecting the transmitted data. This reduces the size of the receiver since a vector sensor measures the scalar and vector components of the acoustic field at a single point in space. In other words, multiple channels in the proposed receiver are co-located. This is different from
conventional multichannel underwater acoustic receivers, which employ spatially separated pressure-only sensors that may result in large arrays. The small size of the proposed receiver makes it particularly useful for small unmanned underwater vehicles and some underwater wireless sensor networks [4].