ANSI/SCTE 144 2023

Test Procedure for Measuring Transmission and Reflection

Executive Summary

This test procedure describes the techniques used to characterize radio frequency (RF) components and subsystems by measuring their transmission and reflection characteristics. The resulting measurements can be used to compare the performance of various devices as well as predict overall network performance when multiple devices are used together.


The purpose of this test procedure is to determine the reflection at any port, or the transmission between any two ports of a properly terminated device, as measured across a frequency range of interest. Depending on use of the data, return loss, insertion gain or loss, isolation, response variation or bandwidth can be derived.

This specification is designed for devices with a characteristic impedance of 75 ohms. However, these principles can easily be extended to devices of other characteristic impedances.