Roll-off factor of filter

A: The rolloff rate is the rate of change of the output of the filter versus frequency. It is expressed as a loss per decade (a ten-times increase in frequency) or per octave (a two-time increase in frequency.

1. How do you calculate roll-off factor?
2. What is the ideal roll-off factor?
3. What is roll-off effect?
4. What is the roll-off factor of first order filter?

How do you calculate roll-off factor?

The choice of the roll-off factor Alpha (that belongs to [0,1]) is a trade-off between several parameters : - the bandwidth of the baseband signal is equal to [-(1+ALpha)/2,(1+ALpha)/2] to determine the Spectrum shape of teh modulated signal.

What is the ideal roll-off factor?

A better compromise would be a roll off factor somewhere between 0.25 and 0.5 (B and C). Here the impulse response decays relatively quickly with small lobes, requiring a pulse shaping filter with a small number of taps, while still keeping the required bandwidth reasonable.

What is roll-off effect?

Roll-off effect is an anomaly that arrises with UWMA, EWMA and other types of inference procedures. If a fixed window of historical data is used by an inference procedure, there are periodic drops in calculated value-at-risk resulting from extreme historical data points expiring from the window.

What is the roll-off factor of first order filter?

All first-order filters have a 20 dB/decade roll-off. The same roll-off can also be specified as 6 dB/octave. An octave is a term borrowed from music and represents a doubling of frequency.