In practice an analog signal is subject to electronic noise and distortion introduced by communication channels and signal processing operations, which can progressively degrade the signal-to-noise ratio.

Therefore as analog signal processing systems become more complex, they may ultimately degrade signal resolution to such an extent that their performance is surpassed by digital systems.

* Analog signal processing

* Analog signal processing, processing electronic signals that represent continuous variables by use of analog circuitry

Audio signal processing, sometimes referred to as audio processing, is the intentional alteration of auditory signals, or sound, often through an audio effect or effects unit.

As audio signals may be electronically represented in either digital or analog format, signal processing may occur in either domain.

Analog signal processing ( ASP ) then involves physically altering the continuous signal by changing the voltage or current or charge via various electrical means.

Since that time, as computers and software became more advanced, digital signal processing has become the method of choice.

This permits signal processing using digital circuits such as microprocessors and computers.

Although such a conversion can be prone to loss, most modern audio systems use this approach as the techniques of digital signal processing are much more powerful and efficient than analog domain signal processing.

Here a musical signal is tuned to the correct pitch using digital signal processing techniques.

It is often used in signal processing for analyzing functions or series of values, such as time domain signals.

* In signal processing, autocorrelation can give information about repeating events like musical beats ( for example, to determine tempo ) or pulsar frequencies, though it cannot tell the position in time of the beat.

Signal processing would be applied to determine the direction of maximum illumination and so develop a signal to steer the antenna toward the target.

Bandwidth in hertz is a central concept in many fields, including electronics, information theory, digital communications, radio communications, signal processing, and spectroscopy.

In many signal processing contexts, bandwidth is a valuable and limited resource.

where w ( t ) is the window function, commonly a Hann window or Gaussian bell centered around zero, and x ( t ) is the signal to be transformed.

In the aforementioned article, the use of the Hann window is called " hanning ", e. g., " hanning " a signal is to apply the Hann window to it.

Bessel functions also have useful properties for other problems, such as signal processing ( e. g., see FM synthesis, Kaiser window, or Bessel filter ).

After each burst, the electronics looks for a return signal within a small window of time corresponding to the time it takes for the energy to pass through the vessel.

Only signal received during this window period will qualify for additional signal processing.

The dry signal will not be received within this window, and therefore will be ignored.

Her birth was an event as all of the neighbors gathered around Juanita's bedroom window, waiting for the raising of a curtain to signal the baby ’ s arrival.

* Gating signal, a signal that provides a time window

It also reduces both the noise margin and the window in which the signal can be sampled, which shows that the performance of the system will be worse ( i. e. it will have a greater bit error ratio ).

It can be implemented by multiplying by a window in the quefrency domain and when converted back to the frequency domain, resulting in a smoother signal.

For example, " simple truncation sinc causes severe ringing artifacts ," in signal reconstruction, and to reduce these artifacts one uses window functions " which drop off more smoothly at the edges.

Some signal processing researchers negate the random walk hypothesis that stock market prices resemble Wiener processes, because the statistical moments of such processes and real stock data vary significantly with respect window size and similarity measure.

Other noteworthy Amiga framebuffer based cards were: the Impact Vision IV24 graphics card from GVP, an interesting integrated video suite, capable of mixing 24-bit framebuffer, with Genlock, Chromakey, TV signal pass-thru and TV in a window capabilities ; the DCTV a graphics card and video capture system ; the Firecracker 32-bit graphics card ; the Harlequin card, the Colorburst ; the HAM-E external framebuffer.

However, the spectral density of small " windows " of a longer signal may be calculated, and plotted versus time associated with the window.

The Kaiser window is a one-parameter family of window functions used for digital signal processing, and is defined by the formula

In signal processing, a window function ( also known as an apodization function or tapering function ) is a mathematical function that is zero-valued outside of some chosen interval.

When another function or a signal ( data ) is multiplied by a window function, the product is also zero-valued outside the interval: all that is left is the part where they overlap ; the " view through the window ".

Terms and concepts such as transform theory, spectrum, bandwidth, window functions and sampling from one dimensional signal processing are commonly used.

The Fourier transform ( a one-dimensional function ) of the resulting signal is taken as the window is slid along the time axis, resulting in a two-dimensional representation of the signal.

likewise, with signal x and window w. In this case, m is discrete and ω is continuous, but in most typical applications the STFT is performed on a computer using the Fast Fourier Transform, so both variables are discrete and quantized.

In addition to the authentication and acknowledgment procedures which precede and follow the sending of the go messages, again in special codes, each message also contains an `` internal authenticator '', another specific signal to convince the recipient that he is getting the real thing.

By this standard, it is determined that where two stations operating on the same frequency are involved, objectionable interference from station A exists at any point within the service area of station B where station A's signal is of an intensity one-twentieth or more of the strength of station B's signal at that point.

For this reason, the more uncertain skywave service was denominated `` secondary '' in our rules, as compared to the steadier, more reliable groundwave `` primary service '', and, for both skywave service and skywave interference, signal strength is expressed in terms of percentage of time a particular signal-intensity level is exceeded -- 50 percent of the time for skywave service, 10 percent of the time for skywave interference.

The design of a mechanical interlocking frame is much like a mechanical puzzle, but once understood, the principles can be applied to any track and signal arrangement.

If the lever is pulled to clear a signal or move a switch, the tappet moves a short distance lengthwise at the same time.

By this scheme, pulling one signal to clear locks all the other switch and signal levers in safe positions until the first signal is again restored to normal.

As an engineer approaches the plant the position of the home signal is seen in advance when he passes the `` distant '' signal located beyond the limits of the interlocking plant.

In some low-speed situations, the distant signal is fixed at caution.

The video signal is amplified and then switched, in synchronism with the three ultraviolet light sources which are sequenced by the rotating mirror so that during one-twentieth of a second only one wavelength, corresponding to red, green, or blue, is seen.

The electrical signal from the autocollimator is amplified and supplied to the Z-gyro torquer.

Essentially, the stator or reference portion of the pickoff is established with respect to the true heading direction, and the platform is turned either manually or automatically until the angular electrical pickoff signal is reduced to zero.

`` The pattern '', says Dr. Morton Schillinger, psychologist at New York's Lincoln Institute for Psychotherapy, `` is for the husband to hover about anxiously and eagerly, virtually trembling in his hope that she will flash him the signal that tonight is the night ''.

I said `` Darn it, that's the automatic signal that shows when the ignition key is on.

As soon as that one man is appointed by himself or the others or by a signal from Spencer, we are going to be rushed.