User's Manual

Radical-7 Chapter 1: Technology Overview
www.masimo.com 32 Masimo
Signal Processing
The digital signal produced by the acquisition system is converted into a measurement that
corresponds to the respiratory parameter of interest. As shown in the previous figure, this
can be performed by, for example, determining the digital signal envelope or outline which
in turn may be utilized to determine the respiratory rate. In this way, a real-time, continuous
breath rate parameter can be obtained and displayed on a monitor which, in many cases,
may be real-time and continuous.
The respiratory cycle envelope signal processing principle is similar to methods that sample
airway gasses and subsequently determine a respiratory rate.
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sounds. J Appl Physiol 1996; 80: 5-13.
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