IRIS - Imaging Riometer for Ionospheric Studies

IRIS is an imaging riometer, located at Kilpisjärvi, not too far from KAIRA. It is a single-frequency riometer and images the ionospheric absorption using fixed multibeams (unlike KAIRA which uses both fixed and tracking beams, as well as interferometry). The IRIS beams are formed using Butler matrices.IRIS is operated by the University of Lancaster, UK, with assistance from SGO. It is quite an old instrument and has been operating since September 1994. Its receiver frequency is 38.2 MHz. KAIRA often runs experiments at similar frequencies (for us, subband 195) in order to carry out comparative experiments.

IRIS (Photo: D. McKay-Bukowski)