Smoothing apparatus for peak windowing

A smoothing apparatus for peak windowing, comprising:

• an operator configured to generate a first input signal for smoothing using an input signal for peak windowing and a predetermined clipping threshold level;
• a first filter block configured to filter the first input signal using a first gain and a first window coefficient combination including first window coefficients for low pass filtering, which have a symmetric structure;
• a subtractor configured to subtract an output of the first filter block from the first input signal;
• a maximum operator configured to generate a second input signal including one of each sample of an output of the subtractor and ‘0’, whichever is greater than the other;
• a second filter block configured to filter the second input signal using a second gain and a second window coefficient combination including second window coefficients for low pass filtering, which have an asymmetric structure;
• and
• an adder configured to generate a smoothed signal by adding an output of the first filter block to an output of the second filter block.

A smoothing apparatus for peak windowing, comprising:

• an operator configured to generate a first input signal for smoothing using an input signal for peak windowing and a predetermined clipping threshold level;
• a subtractor configured to subtract a feedback signal from the first input signal;
• a maximum operator configured to generate a second input signal including one of each sample of the subtracted signal and ‘0’, whichever is greater than the other;
• a feedback path configured to generate a feedback signal for a next input signal by multiplying samples of the second input signal by window coefficients in the first window coefficient combination and sum up the multiplication results;
• a comparator configured to compare a ratio of the feedback signal to the first input signal, with at least one predetermined threshold;
• a filter block configured to filter the second input single depending on the comparison result using window coefficients in a second window coefficient combination for low pass filtering;
• and
• a summer configured to generate a smoothed signal by summing up outputs of the filter block.