Instrument Support Level 4
3 GHz Chilbolton Advanced Meteorological Radar (CAMRa)
The Chilbolton Advanced Meteorological Radar (CAMRa) is an S-band dual-polarization Doppler radar based on a fully steerable 25 m diameter dish antenna, a magnetron transmitter, a dual-channel superheterodyne receiver, and a hybrid analogue-digital signal processor. The radar uses a digital signal processing scheme to achieve coherent-on-receive operation. The radar transmits alternately horizontally and vertically polarised pulses and receives both co-polar and cross-polar returns. This approach permits real-time measurement and display of Z, ZDR, LDR, v, w, φDP, KDP and ρHV. For more detailed studies, full time-series measurements of I and Q are also possible over a large number of range-gates and transmitted pulses.
Typical research areas for which CAMRa is used include rainfall rate estimation, hydrometeor characterization (with aircraft verification), effects of precipitation on terrestrial and earth-space radio propagation, multi-wavelength studies of cloud and precipitation, clear-air and boundary layer investigations and satellite sensor ground-truth verification. It is operated on a case-study basis.
A detailed description of the radar sub-system hardware and of the signal processing scheme, together with examples of typical measured data, is given in ‘The Chilbolton Advanced Meteorological Radar: a tool for multidisciplinary atmospheric research’ by J. W. F. Goddard, J. D. Eastment and M. Thurai. IEE Electronics and Communications Engineering Journal, April 1994. Vol. 6, No. 2. pp 77 – 86.