Sotiris A. Tegos

Radar, like a bat in a cave, sends out a pulse and listens for the echo. But a microscopic imbalance in the receiver is unavoidable: it scrambles frequencies and creates a phantom twin for each target, like a second, slightly distorted echo. Usually, these phantoms just get in the way and are cleaned up beforehand. In this new work, ghost echoes become an ally.

Radars listen to the echo of radio waves, like a microphone recording music. To make equipment cheaper, the 'recording' is done less frequently than theory demands: this is spectrally efficient (compressed) sensing. The cost of this economy is the emergence of false 'ghosts': the system sees targets that aren't there, just like off-key notes on old tape.