This document describes two methods for determining and measuring the information transmission capacity of TIA/EIA-4920000-B Class I (glass core) multi-mode optical fibers. The baseband frequency response is directly measured in the frequency domain by determining the fiber response to a sinusoidally modulated light source. The baseband response can also be measured by observing the broadening of a narrow pulse of light. The two methods are:
Method A – Optical Time Domain Measurement Method (Pulse Distortion)
Method B – Frequency Domain Measurement Method
Each method can be performed using one of two launches: an overfilled launch (OFL) condition or a restricted mode launch (RML) condition.
Note: These test methods are commonly used in production and research facilities and are not easily accomplished in the field.
