Method of displaying digital data provided in polar coordinates by a panoramic scanning device, such as a radar, sonar apparatus or the like, on a screen frame with Cartesian coordinates

摘要

In the method, after coordinated transformation the data are written into a frame buffer, which can be addressed in cartesian coordinates, using a storage organisation corresponding to the screen raster, and read out from the frame buffer by row or column and visually displayed on the screen. For the purpose of data reduction without worsening the resolution of the panoramic picture, the increment of the angular coordinate is chosen to be larger by an order of magnitude than the azimuthal resolution of the frame buffer, and is preferably between half the value and the full value of the aperture angle of the scanning member of the panoramic scanning device. In accordance with the azimuthal resolution of the frame buffer, a non- redundant set of cartesian input addresses, whose upper and lower boundaries are determined by the angular coordinate increment, is generated for each pair of values of polar coordinates in such a way that all the memory locations of the frame buffer which are necessary for the panoramic representation can be addressed through the totality of the address records. The same data are written in each case into the memory locations which can be addressed in the address records in each case.