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The effect of a non-ideal integrator, i.e., finite gain
degrades the noise performance to some
extent. The integrator frequency response can be modeled as
![\begin{displaymath}
H(s) = \frac{1
}{s\tau_0 + 1/A} = \left\{
{
\begin{array...
.../s\tau_0 & 1/A\tau_0 < \vert s\vert \\
\end{array}} \right.
,
\end{displaymath}](img821.gif) |
(B.6) |
where A is the integrator gain. This sets a lower limit to the
noise power spectral density and to the achievable SNR:
![\begin{displaymath}
S/N = \frac{\left<\left\vert x(t)\right\vert^2\right>}{\left<\left\vert e(t)\right\vert^2\right>} A
.
\end{displaymath}](img822.gif) |
(B.7) |
G. Schrom