Peak Detection
Detecting peaks is a basic function that underlies all operations because it is common to both amplitude and frequency metrics, and calculations of amplitude and frequency are made continuously by the system.
Sample to sample changes in amplitude are tracked to determine transitions from a positive to negative first derivative (slope). When a peak is detected, its real time level is immediately available for amplitude related measurements. Also, its sample index is saved, and when the next peak is detected, the real time frequency is computed based on the time between peaks.
Frequency, F is the reciprocal of time, t. F=1/t, and each sample represents a unit of time equal to 1/Sample Frequency.