The current sources which are normally used in research laboratories are not suitable for low noise measurement systems because of the unacceptable level of low frequency noise which they introduce in the measurement chain. The most important source of low frequency noise in such instruments is the solid state device (usually a Zener diode) which is used as voltage reference. By using a novel c...

The noise behavior of bulk CMOS devices is dominated primarily by two noise sources: thermal noise and flicker (1/f) noise. Other sources that are sometimes present in the noise spectrum are shot noise, generation/recombination noise, and “popcorn” noise. Of these sources, thermal noise and shot noise are physically fundamental to the operation of the device and are always present. The quality ...

The diagnostics of the noise acoustical sources from near-field data is considered. The algorithms allowing the determination of the equivalent elementary source distribution along a radiator and the far-field reconstruction from near-field measurements are presented. Some components of the total reconstruction error are analyzed.

the mixture of natural and artificial seismic sources with random distributions cause diffuse wave field with random amplitudes and phases called noise. when noise is analyzed in a long-term process, it contains surface waves which are spread in all directions. thus, ambient noise contains data relevant to the surface waves. in recent years, as broadband seismic networks have been distributed v...