Vector Mapping Software
Our mapping software allows one to set up an experimental folder, first setting the latitude-longitude co-ordinates of each of up to nine transmitter sites. One can specify either a monostatic or a monostatic-bistatic combination. One then sets the desired map boundaries, specifying the latitude-longitude co-ordinates of the corners of the map. We utilize the NOAA data sets to draw the coast line within this area, and the range bin circles/ellipses for the site combinations chosen above. An example of such a map is shown below for the entrance to the Chesapeake Bay. The monostatic radar site is at the tip of Cape Henry, while a bistatic site is located at the northern-most island of the three Chesapeake Bay Bridge-Tunnel (CBBT) group of four.
Given a set of radials determined from the Doppler analysis of data from a pair of monostatic sites, or a monostatic-bistatic pair, one combines these radials to form current or target velocity vectors. A grid of desired vector locations is chosen by specifying the corners of the grid, then the spatial density in fractions of a degree in both latitude and longitude. An example of such a grid is shown below, but with slightly different radar resolution. Vectors are determined using weighted averages of nearest neighbor range-azimuth radial samples.
A simulation of radials is shown below for a monostatic site in the Florida keys. The current vector used to generate the radials used a fixed direction from east to west across the scene, and radials were calculated at each of the chosen lat-lon positions for the radar resolution chosen. The code then chose the nearest range-azimuth data sample set of four, weighted each according to its local radial distance from the desired point, and determined the effective radial at that point. A similar calculation is done at the same points for the radar data from the second site and these are then combined to derive a vector for each point. For the case above, the resultant vector map retrieved the input east-to-west current vector.
Maps of this type are then stored in JPEG format for display and the actual vector data are stored in text format for operational analysis if desired.
We have developed the capability to automatically download the JPEG and text files from the radar site to an analysis site at a home base, and plan to demonstrate this capability with real time maps on our web site.