Phase-divergent carrier wave

From Memory Alpha, the free Star Trek reference

A phase-divergent carrier wave was a type of carrier wave that changed phases, making it difficult to trace.

Trentin Fala used a phase-divergent carrier wave to contact Kira Nerys onboard Deep Space 9. Her signal was also run through a scrambler, which made it particularly difficult to trace the source. (DS9: "The Darkness and the Light")