US Patent 10270482 Automated avionics testing

An SDR system and method that intentionally illuminates aircraft systems with RF energy having specific characteristics (e.g., frequency, power, waveform, directionality, duration, etc.) are provided. The aircraft systems act as non-linear mixers and emit non-linear RF energy. A receiver receives the RF energy response and generates an RF energy representation that is correlated to a database of baseline responses. A correlation response between the received RF energy representation and any one of the baseline responses from the database provides an indication of the aircraft system status.