A precipitation profiler simulator

As the cost of wind profiler technology decreases, more meteorologists are using vertically pointing profilers to study the microphysical and dynamical processes of precipitating cloud systems. A profiler simulator has been developed that incorporates user defined atmospheric conditions, radar attributes, and signal processing steps needed to replicate Doppler velocity power spectra obtained from a vertically pointing precipitation profiler. This virtual profiler is useful in performing sensitivity studies of radar operating parameters and signal processing techniques under different precipitation conditions. For example, changes in the estimated Doppler velocity power spectra can be investigated in response to small changes to the raindrop size distribution.

This profiler simulator is a forward simulator with the backscattered energy from each transmitted radar pulse processed using the same time-domain processing used by commercial profilers. The user defines both atmospheric conditions and radar attributes within the profiler simulator. Regarding the column of atmospheric conditions, the user gets to define profiles of temperature, humidity, horizontal and vertical wind speed, raindrop size distributions, frozen particle habits and their size distributions. The user also defines the diameter-to-fall speed relationship of each raindrop size and of each frozen particle size for each ice habit. The user also has control over the backscattered cross-sectional area of each hydrometeor which will be dependent on the profiler operating frequency.

Regarding the radar operating parameters, the user defines the operating frequency, the radar beam width, and the transmitted power. The user also has control over all signal processing parameters including the number of coherent integrations, number of points in the FFTs, the number of incoherently averaged spectra. In addition to the simulator being useful for performing radar sensitivity studies, the simulator can also investigate new signal processing techniques for the next generation of profiling radars.