A 32-element frequency-steered array antenna for reflectometry in W-band

In fusion plasma experiments, Doppler reflectometry is used as a contactless diagnostic to evaluate density fluctuations and plasma rotation profiles. It demands a steerable beam that provides a defined spot-size for the wave plasma interaction and multiple frequencies to probe plasma regions of different densities. In this paper, the suitability of a frequency-scanned phased array as a front-end for a Doppler reflectometry system is demonstrated.