FMCW phased array radar for automatically triggered measurements of snow avalanches

Radar has emerged as a means of measuring avalanche dynamics for validating models to predict avalanche behaviour for improved calculation of risk zones. However, current radar measurements do not provide a true representation of an entire avalanche flow. An FMCW, multi-chirp, 8 receiver channel phased array radar has been developed in attempt to provide 2-D field measurements in unparalleled detail. In this paper, we summarise the design of the radar and discuss further additions to the radar design since a previous report. The radar is deployed in a bunker at well-equipped avalanche test site where it has been automatically recording naturally occurring avalanches. Several avalanches have been recorded including a large wet snow avalanche which occurred on the 7th December 2010 has already been recorded. We present an encouraging MTI image of this avalanche from one of the receiver channels which reveals a wealth of information embedded within the data. In the future we hope to cohere the 8 channels of data to provide cross-range information, and also resolve the range and Doppler of various components of the avalanche.