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Topic: To design a

Notch filter having

central frequency

3.1206 KHz

Submitted by:-

Sushil Kumar Mishra

ECE-I

05311502809

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Introduction:

In signal processing, a band-stop filter or band-rejection filter is a filter that passes most frequencies unaltered, but attenuates those in a specific range to very low levels. It is the opposite of a band-pass fil-ter. A notch filter is a band-stop filter with a narrow stopband (high Q factor).

Narrow notch filters (optical) are used in Raman spectroscopy, live sound reproduction (public address systems, or PA systems) and in instrument amplifiers (especially amplifiers or preamplifiers for acous-tic instruments such as acoustic guitar, mandolin, bass instrument am-plifier, etc.) to reduce or prevent audio feedback, while having little no-ticeable effect on the rest of the frequency spectrum (electronic or software filters). Other names include 'band limit filter', 'T-notch filter', 'band-elimination filter', and 'band-reject filter'.

Typically, the width of the stopband is 1 to 2 decades (that is, the high-

est frequency attenuated is 10 to 100 times the lowest frequency atten-

uated). However, in the audioband, a notch filter has high and low fre-

quencies that may be only semitones apart.

Fig.1 A generic ideal band-stop filter, showing both positive and nega-

tive angular frequencies

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Circuit diagram snapshots:

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Simulation output:

Result : Notch filter having central frequency 3.1206 KHz has

been made on orcad and simulated. Trace has been taken.