Random or incoherent noise is an important type of seismic noise, which can seriously affect the quality of the data. Therefore, decreasing the level of this category of noises is necessary for increasing the signal-to-noise ratio (SNR) of seismic records. Random noises and other events overlap each other in time domain, which makes it difficult to attenuate them from seismic records. In this r...

An analog queue-based architecture and an adaptive digital-calibration algorithm calibrate an 8-bit two-stage pipelined algorithmic analog-to-digital converter (ADC). To minimize power dissipation and noise, the queue consists of only one sample-and-hold amplifier. At a sampling rate of 20 Msamples/s, the peak signal-to-noise-and-distortion ratio (SNDR) is 45 dB, and the spurious-free dynamic r...

Its wide dynamic range makes the spectrum analyzer the test instrument of choice for measuring harmonic distortion, intermodulation distortion, adjacent channel power ratio, spurious-free dynamic range, gain compression, etc. Distortion measurements such as these are bounded on one side by the noise floor of the spectrum analyzer and on the other side by the signal power strength at which the s...

In many kinds of equipment, it is important to produce readily control accurate waveforms of various frequencies and profiles such as agile frequency sources with low phase noise and low spurious signal content for communications, and simply generated frequency for industrial and biomedical applications. A direct digital synthesizer (DDS) provides many significant advantages over the PLL approa...

A measurement method is proposed to characterize the substrate coupling between digital and analog sections of a mixed-signal CMOS chip. Induced noise and spurious signals can be measured by a custom-designed analog sensor. This paper proposes a method that, when given such a sensor, allows to measure the crosstalk between digital and analog chip sections. Calibrated sampling scope measurements...

Magnetic resonance force microscopy can enable nanoscale imaging of spin lifetime. We report temperaturedependent measurements of the spin correlation time τm of the statistical fluctuations of the spin polarization—the spin noise—of ensembles containing ∼100 electron spins by this technique. Magnetomechanical relaxation due to spin-cantilever coupling was controlled and spurious mechanisms tha...

Functional Magnetic Resonance Imaging (fMRI) can detect venous concentration changes of deoxygenated hemoglobin. Cerebral blood flow is locally regulated by pre-capillary arteriolar smooth muscles [1]. Consequently, fMRI images inherit the spatial characteristic of localised signal change. In addition, spurious voxels also exhibit significant fluctuations due to instrumental and physiological n...

This paper proposes a new pitch detection algorithm of speech signals in noisy environment. The performance of the cepstrum method is effected due to the formant effect and the presence of spurious peaks introduced in noisy condition. In our proposed method, we firstly employ windowless autocorrelation function instead of its speech signal for obtaining the cepstrum. The windowless autocorrelat...

Electrical Neurostimulation has been effective in several medical therapies and also for restoring physiological, sensory and neuromuscular deficits. The rectangular pulse waveform has been used as a standard shape for neural stimulation. However, it has been shown that non-rectangular waveforms provide a more energy-efficient neural stimulation. An ASIC has been developed composed of a stimula...

We present a comprehensive study of the effect of detector sampling on wavefront-coded systems. Two important results are obtained: the spurious response ratios are reduced in wavefront-coded systems with a cubic phase mask and detector sampling does not compromise the restoration of wavefront-coded images with extended depth of field. Rigorous computer simulation of sampled wavefront-coded ima...