Embodiments of the invention include devices and methods for searching IQ-based time-domain traces for events, marking the events, and analyzing intervals of interest at or around the events on a display unit of a test and measurement instrument. The test and measurement instrument can include an input terminal to receive an RF signal, an ADC to digitize the RF signal, a digital downconverter to produce I (in-phase) and Q (quadrature) baseband component information from the digitized RF signal, an acquisition memory to acquire and store a record, a trace generation section to generate one or more IQ-based time-domain traces, and a search unit to scan the IQ-based time-domain traces for one or more events. The search unit can locate and mark the events for display on a display unit of the test and measurement instrument.