PPI To raster display scan converter
US4547803A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 27, 1981 |
| Grant date | Oct 15, 1985 |
| Priority date | — |
| Expiry date | Nov 27, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S7/298
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A raster display apparatus for converting radar input data which is formatted to produce a Plan Position Indicator (PPI) presentation on a cursive display to a format which achieves a PPI type image on a raster display. The apparatus generates radar images on a raster display screen which appear as targets having continuous arcs of the proper length around the placement position of a radar. Average video levels within successive discrete fixed azimuthal standard angle increments are stored in a radial buffer memory for various increments of range. These video levels are used for all points within the presently active standard angular increment. Radial distance of a given image is computed for changes in orthogonal components such as X or Y using simple prestored sine and cosine functions. Conversion calculations comprise primarily additions using adders. The video amplitude of the image displayed is equal in amplitude to the video level of the input data stored in the radial video buffer memory for the standard angle being processed. Processing of successive standard angle increments proceeds in approximate synchronism with the input data being provided in a cursive display format.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.