Another assumption on the input signal is that it is a wide-band
signal with the spectral properties of white noise.
Let the spectrum of the input signal be
S_{in}
.
The mean squared output signal
of integrator i
is then

= S_{in}| f_{i}|_{2}^{2}

(18)

where

| f_{i}|_{2}^{2}S_{i}(ω)| f_{i}(jω)|^{2}dω.

(19)

S_{i}(ω)
is an input weighting function that is by default identical
to 1.
If the maximally allowed signal level at the outputs of the integrators
is
V_{max}
, the maximum allowed value for
S_{in}
is

S_{max, in} = .

(20)

If H
is the transfer function of the filter, the maximum output signal
level of the filter is