Data acquisition, triggering, and filtering at the Auger Engineering Radio Array

The Auger Engineering Radio Array (AERA) is currently detecting cosmic rays of energies at and above 10 17 eV at the Pierre Auger Observatory, by triggering on the radio emission produced in the associated air showers. The radio-detection technique must cope with a significant background of man-made radio-frequency interference, but can provide information on shower development with a high duty cycle. We discuss our techniques to handle the challenges of self-triggered radio detection in a low-power autonomous array, including triggering and filtering algorithms, data acquisition design, and communication systems.