A measure of the power of the outgoing signal to the power of the reflected signal expressed in decibels is known as ____________.

Return loss is a key concept in telecommunications and signal transmission. It measures the effectiveness of the output signal in comparison to the reflected signal that occurs due to impedance mismatches in a transmission line. By expressing this measurement in decibels (dB), return loss allows for easy interpretation of how much signal power is lost due to reflections, with a higher return loss indicating a better match and less power reflected back.

In practical terms, a high return loss implies that most of the signal is being transmitted effectively without reflection, which is a desirable characteristic in communication systems. This is crucial for maintaining signal integrity and minimizing disruptions in the transmission of data.

The other choices, while related to signal quality and transmission characteristics, serve different purposes. For instance, signal-to-noise ratio measures the level of desired signal in relation to background noise, transmission loss refers to the total loss of signal power as it travels through a medium, and reflection coefficient quantifies the ratio of the reflected wave amplitude to the incident wave amplitude. However, none of these options specifically measure the outgoing versus reflected signal power in the context defined in the question as return loss does.