enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Cutoff frequency - Wikipedia

    en.wikipedia.org/wiki/Cutoff_frequency

    The cutoff frequency is the critical frequency between propagation and attenuation, which corresponds to the frequency at which the longitudinal wavenumber is zero. It is given by ω c = c ( n π a ) 2 + ( m π b ) 2 {\displaystyle \omega _{c}=c{\sqrt {\left({\frac {n\pi }{a}}\right)^{2}+\left({\frac {m\pi }{b}}\right)^{2}}}} The wave equations ...

  3. Alpha cutoff frequency - Wikipedia

    en.wikipedia.org/wiki/Alpha_cutoff_frequency

    Alpha cutoff frequency, or is the frequency at which the common base DC current gain drops to 0.707 of its low frequency value. The common base DC current gain is the ratio of a transistor's collector current to the transistor's emitter current , or α = i C i E {\displaystyle \alpha ={\frac {i_{C}}{i_{E}}}} .

  4. Half-power point - Wikipedia

    en.wikipedia.org/wiki/Half-power_point

    The half-power point is the point at which the output power has dropped to half of its peak value; that is, at a level of approximately −3 dB. [1] [a]In filters, optical filters, and electronic amplifiers, [2] the half-power point is also known as half-power bandwidth and is a commonly used definition for the cutoff frequency.

  5. Roll-off - Wikipedia

    en.wikipedia.org/wiki/Roll-off

    For some filter classes, such as the Butterworth filter, the insertion loss is still monotonically increasing with frequency and quickly asymptotically converges to a roll-off of 20n dB/decade, but in others, such as the Chebyshev or elliptic filter the roll-off near the cut-off frequency is much faster and elsewhere the response is anything ...

  6. Fourier shell correlation - Wikipedia

    en.wikipedia.org/wiki/Fourier_shell_correlation

    In structural biology, as well as in virtually all sciences that produce three-dimensional data, the Fourier shell correlation (FSC) measures the normalised cross-correlation coefficient between two 3-dimensional volumes over corresponding shells in Fourier space (i.e., as a function of spatial frequency [1]).

  7. Spatial cutoff frequency - Wikipedia

    en.wikipedia.org/wiki/Spatial_cutoff_frequency

    As an example, a telescope having an f /6 objective and imaging at 0.55 micrometers has a spatial cutoff frequency of 303 cycles/millimeter. High-resolution black-and-white film is capable of resolving details on the film as small as 3 micrometers or smaller, thus its cutoff frequency is about 150 cycles/millimeter.

  8. Cutoff - Wikipedia

    en.wikipedia.org/wiki/Cutoff

    Cutoff (reference value), a one-sided reference range in health-related fields. Cutoff (steam engine), the point in the piston stroke at which the inlet valve is closed. Cutoff frequency, in telecommunications and digital signal processing. Cutoff grade, in mining, the level of mineral in an ore below which it is not economically feasible to ...

  9. Cut-off frequency - Wikipedia

    en.wikipedia.org/?title=Cut-off_frequency&...

    From Wikipedia, the free encyclopedia. Redirect page