Robust method for signal segmentation for motion classification in personal navigation

A method to accurately detect true peaks and true valleys in a real-time incoming signal is provided. The method includes segmenting the real-time incoming signal into short-time intervals; determining an initial estimated frequency by fast Fourier transforming data in the short-time intervals, setting a sliding window width based on the initial estimated frequency, determining at least one peak data element or valley data element based on analysis of the real-time incoming signal within a first sliding window; and determining at least one peak data element or valley data element based on analysis of the real-time incoming signal within a second sliding window. A first portion of the second sliding window overlaps a second portion of the first sliding window.