Pre-launch testing of space vehicles is a complex process taking weeks if not months to accomplish. An onboard structural health monitoring system is considered for reduction of testing time and component validation. The active elements of the system, embedded sensors, are used to transmit and receive elastic waves carrying information on component characteristics and structural integrity. Parameters of the elastic wave recorded with embedded sensors are investigated using several measurement methods coupled with temporal analysis of elastic wave signatures. In particular, attention is given to temporal distribution of signal phase and nonlinear effects. Specimens of simple and complex geometry incorporating defects typical to space structures are considered in experimental studies. Local measurements with a single sensor as well as global assessment of structural components with a sensor network were explored for damage detection, characterization, and location. Proposed diagnostic approaches were validated on a realistic satellite panel with isogrid reinforcement. Conclusions are presented on sensing capabilities of active sensors and effectiveness of the associated signal analysis.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.