Benefit of using digital filter as compared to the analog filter?

Question

The effect and impact of filter length chosen

Answer 1

Filter synthesis of analog filter is very difficult, and implementation is hampered by non-ideal components (capacitors, inductors). The synthesis may call for unusual values of these components (like 14.2 microfarad or 3.6 millihenrys) that you can't get at an electronics store. You use the nearest standard values, but then your filter is not exactly right. You do not have this problem with digital filters. You can design a wide variety of filters to a high degree of accuracy, depending on the number of elements (multipliers/accumulators) and samples (filter length) you a willing to include in your device or program. More samples means you can get sharper cutoff characteristics. Besides cost and memory space, long length filters introduce time delay in the output. One class of digital filters (finite impulse response) is inherently stable and has a linear phase vs frequency characteristic which means no phase distortion. That type of filter requires more elements and samples than the infinite impulse response (IIR) design. The IIR can be made to mimic analog filters, but they can become unstable (oscillate), and can introduce phase distortion.

A major advantage of digital filters is that its parameters are easily changed. A continuously adjustable filter is difficult to do with analog circuits since variable capacitors and inductors are needed. Even op-amp synthesized analog filters (which can be made without inductors) are not easily varied because several stages have to be controlled. For a digital filter, all you have to do is to load different coefficients into the multiplier circuits or algorithms.

Answer 2

There are reasons for employing the two. you will possibly desire to know the features of your subject previously you may opt for. as an occasion the skill. For sign processing, digital filtering could be terrific, yet you may no longer filter out a skill grant output employing a working laptop or pc.

Answer 3

Depends on the function of the filter, simple band-pass and frequency filters for example are more economical as analog.

Answer 4

You can get highly complex filtering, and change it by fiddling bits instead of playing with a soldering iron. Much easier.