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IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2017
Acoustically hard objects, such as bones, needles, or catheters, are poorly visualized in conventional ultrasound images. These objects behave like acoustic mirrors and reflect sound in specific directions. Soft tissue and diffusive reflectors scatter sound in a broad range of directions.
Alfonso Rodriguez-Molares +3 more
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Acoustically hard objects, such as bones, needles, or catheters, are poorly visualized in conventional ultrasound images. These objects behave like acoustic mirrors and reflect sound in specific directions. Soft tissue and diffusive reflectors scatter sound in a broad range of directions.
Alfonso Rodriguez-Molares +3 more
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Smooth Beamforming and Efficient Beamforming Weight Computation
IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference, 2007This paper investigates an efficient way of computing the beamforming weights for a MIMO OFDM system. It is shown that computing the weights incrementally across correlated channels can significantly reduce the complexity. An additional benefit of this technique is that it provides a "smooth" beamformer, i.e., it does not significantly change the ...
V. Ponnampalam, Magnus Sandell
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The Journal of the Acoustical Society of America, 2012
There is a great variety of beamforming techniques that can be used for localization of sound sources. The differences among them usually lie in the array layout or in the specific signal processing algorithm used to compute the beamforming output.
Antoni Torras-Rosell +2 more
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There is a great variety of beamforming techniques that can be used for localization of sound sources. The differences among them usually lie in the array layout or in the specific signal processing algorithm used to compute the beamforming output.
Antoni Torras-Rosell +2 more
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2004
Sound emerging from a transducer aperture diffracts or creates a sound field unique to its geometry and frequency content. This field, also called an “acoustic beam,” can be predicted from models that describe the emitting source in terms of spherical (Huygen’s) waves or equivalently, an angular spectrum of plane waves.
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Sound emerging from a transducer aperture diffracts or creates a sound field unique to its geometry and frequency content. This field, also called an “acoustic beam,” can be predicted from models that describe the emitting source in terms of spherical (Huygen’s) waves or equivalently, an angular spectrum of plane waves.
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Adaptive Beamforming Assisted ReceiverAdaptive Beamforming
2009Adaptive beamforming is capable of separating user signals transmitted on the same carrier frequency, and thus provides a practical means of supporting multiusers in a space-division multiple-access scenario. Moreover, for the sake of further improving the achievable bandwidth efficiency, high-throughput quadrature amplitude modulation (QAM) schemes ...
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2004
Because images are formed from pulse echoes, this chapter introduces time domain diffraction approaches that are suited to short pulses. The benefit of the time domain approach is that it involves a single convolution calculation with a pulse. Both time and frequency approaches are used to describe arrays that can be thought of as continuous apertures ...
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Because images are formed from pulse echoes, this chapter introduces time domain diffraction approaches that are suited to short pulses. The benefit of the time domain approach is that it involves a single convolution calculation with a pulse. Both time and frequency approaches are used to describe arrays that can be thought of as continuous apertures ...
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Journal of Medical Ultrasonics, 2017
A number of studies aimed at improvement of ultrasound image quality, such as spatial resolution and contrast, have been conducted. Apodization is known as an important factor that determines image quality. However, in the case of amplitude and phase estimation (APES) beamforming, a kind of adaptive beamformer that has been employed in medical ...
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A number of studies aimed at improvement of ultrasound image quality, such as spatial resolution and contrast, have been conducted. Apodization is known as an important factor that determines image quality. However, in the case of amplitude and phase estimation (APES) beamforming, a kind of adaptive beamformer that has been employed in medical ...
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Performance Comparison between Distributed Beamforming and Clustered Beamforming
2014 11th International Conference on Information Technology: New Generations, 2014The performance of transmit beamforming (BF) systems in terms of the spatial correlation coefficient and channel gain variance (CGV) are analyzed over Rayleigh fading channels. We derive bit error rate (BER) of distributed BF (DBF) systems as a function of CGV of distributed channel links.
Sahar Amini, Dong-jun Na, Kwonhue Choi
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Hybrid beamforming: reduced eigen beamforming on beam signals
2002 International Zurich Seminar on Broadband Communications Access - Transmission - Networking (Cat. No.02TH8599), 2003A hybrid beamforming technique for multiple antenna receivers is introduced. It is a combination of a simple fixed beam method and the adaptive eigen beamforming algorithm. This two-stage solution allows for a user-specific scalable trade-off between performance and complexity, depending on the interference scenario.
G. Schnabl, Ingo Viering, T. Frey
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Transfer Beamforming via Beamforming for Transfer
IEEE Transactions on Mobile Computing, 2023Xueyuan Yang +3 more
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