Signal-to-noise performance of the pulse-interval and width-modulation system

<p>Beamforming filter optimization can be performed over a distributed wireless sensor network, but the output calculation remains either centralized or linked in time to the weights optimization. We propose a distributed method for calculating the beamformer output which is independent of the filter optimization. The new method trades a small decrease in signal to noise performance for a large decrease in transmission power. Background is given on distributed convex optimization and acoustic beamforming. The new model is described with analysis of its behaviour under independent noise. Simulation results demonstrate the desirable properties of the new model in comparison with centralized output computation.</p>

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Ribosome structures to near-atomic resolution from thirty thousand cryo-EM particles

eLife ◽

10.7554/elife.00461 ◽

2013 ◽

Vol 2 ◽

Cited By ~ 310

Author(s):

Xiao-chen Bai ◽

Israel S Fernandez ◽

Greg McMullan ◽

Sjors HW Scheres

Keyword(s):

High Resolution ◽

Structural Biology ◽

Atomic Resolution ◽

Particle Analysis ◽

Full Potential ◽

Single Particle Analysis ◽

Noise Performance ◽

Signal To Noise ◽

Fundamental Limits ◽

New Generation

Although electron cryo-microscopy (cryo-EM) single-particle analysis has become an important tool for structural biology of large and flexible macro-molecular assemblies, the technique has not yet reached its full potential. Besides fundamental limits imposed by radiation damage, poor detectors and beam-induced sample movement have been shown to degrade attainable resolutions. A new generation of direct electron detectors may ameliorate both effects. Apart from exhibiting improved signal-to-noise performance, these cameras are also fast enough to follow particle movements during electron irradiation. Here, we assess the potentials of this technology for cryo-EM structure determination. Using a newly developed statistical movie processing approach to compensate for beam-induced movement, we show that ribosome reconstructions with unprecedented resolutions may be calculated from almost two orders of magnitude fewer particles than used previously. Therefore, this methodology may expand the scope of high-resolution cryo-EM to a broad range of biological specimens.

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Convex Optimization for Distributed Acoustic Beamforming

10.26686/wgtn.17064125.v1 ◽

2021 ◽

Author(s):

◽

Dayle Raymond Jellyman

Keyword(s):

Convex Optimization ◽

Wireless Sensor ◽

Transmission Power ◽

Small Decrease ◽

Noise Performance ◽

Signal To Noise ◽

New Model ◽

Noise Simulation ◽

Simulation Results ◽

Distributed Convex Optimization

<p>Beamforming filter optimization can be performed over a distributed wireless sensor network, but the output calculation remains either centralized or linked in time to the weights optimization. We propose a distributed method for calculating the beamformer output which is independent of the filter optimization. The new method trades a small decrease in signal to noise performance for a large decrease in transmission power. Background is given on distributed convex optimization and acoustic beamforming. The new model is described with analysis of its behaviour under independent noise. Simulation results demonstrate the desirable properties of the new model in comparison with centralized output computation.</p>

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