Remote retuning of X-band mini weather radar using ground clutter echoes

The magnetron of a X-band mini weather radar could drift mainly due to external factors such as temperatures, humidity etc. The central frequency of the radar receiver filter must remain perfectly aligned with the magnetron generated frequency in order to receive the maximum power and avoid rain underestimation problems. This work describe a simple and cheap technique developed to remote retuning a X-band weather radar using ground clutter echoes acquired during clear sky days. By statistically analyzing the power distributions of ground clutter echoes observed in clear sky conditions, it is possible to control the radar stability over a long time interval and to retune the radar. The technique is described and several results are reported.