Experimenting with Shapiro Time Delay Effect

[Nickelodeon]

Here is an excerpt from Wikipedia

The Shapiro time delay effect, or gravitational time delay effect, is one of the four classic solar system tests of general relativity. Radar signals passing near a massive object take slightly longer to travel to a target and longer to return (as measured by the observer) than it would if the mass of the object were not present

Disregarding GR predictions for a moment, how would you experimentally verify whether the delay was contributed by both the travel to and the return or solely by the return run?
..

 

[lippyka]

To experimentally verify whether the delay was contributed by both the travel to and the return or solely by the return run, one could set up a control experiment. In this experiment, two identical radar signals would be sent from the same location, one directly to the target, and the other around the massive object. By comparing the time it takes each signal to reach the target and return, one can determine whether the delay is due to both the travel to and the return or solely by the return run.