Digital Signal Processing Reference
In-Depth Information
Figure 10-5.
PSD of the noises recorded by the primary microphone in various situations: (a)
Sit-Mall1, (b) HWY, (c) CarWOpen, (d) CarWClose.
To objectively measure the system performance, we use the Log Area
Ratio (LAR) metric that has been shown to have the highest correlation with
subjective assessments among all frequency-invariant distance measures
[15]. Given the reflection (Partial Correlation, PARCOR) coefficients of
order
L,
of the
frame, the corresponding Area Ratio
(AR) is defined as [15]:
Here, we have set the order of the reflection coefficients to
L
=
16
. Given
and for the frame of signals
s(n)
(clean speech) and
z(n)
(enhanced output) in Figure 10-1, the LAR distance between the
frames of two signals is calculated as [15]:
