Which of the following best describes upfade in a multipath environment?
The multiple signal paths are distorted and difficult to understand.
Multiple signal paths are not sent at exactly the same time. The receiver receives a positive crest on the primary signal and a negative crest on the secondary signal.
The signal is stronger than it should be because multiple signal paths are received twice at exactly the same time, which results in the multiple signals being in-phase.
The multiple signal paths are weaker than they should be because the signals are out of phase with each other.