Serial scan converter

• US 3,904,817 A
• Filed: 02/01/1974
• Issued: 09/09/1975
• Est. Priority Date: 02/01/1974
• Status: Expired due to Term

• Current Assignee: Glenn C. Waehner, Harvey F. Hoffman
• Original Assignee: Glenn C. Waehner, Harvey F. Hoffman
• Inventors: Waehner, Glenn C., Hoffman, Harvey F.
• Primary Examiner(s): Britton, Howard W.
• Assistant Examiner(s): Masinick, Michael A.
• Application Number:
  US05/438,888
• Time in Patent Office: 585 Days
• Field of Search: 178/DIG.24,6,6.8,7.5R 343/5DP,55C
• US Class Current: 348/442
• CPC Class Codes: G01S 7/298 Scan converters

Abstract

Utilization of a versatile scan-converted display which can operate with a variety of radar sweep signals or a variety of television raster sweep signals permits use of a purely serial main memory for refreshing the display at a rate much higher than radar data acquisition rates, thereby eliminating the need for an expensive random access memory in a multi-source, refreshed, unitary display. The disclosed sources which the scan-converted display will accommodate include air-to-air radar utilizing a depressed center PPI format, a high resolution ground mapping radar utilizing a skewed B-scan with caterpillar advance, a weapon television, the timing of which is controlled by the scan converter, and a landing television which controls the scan converter with its timing.

Claims

1. A scan converter display system adapted for utilization with a plurality of video sources, comprising:

means settable for designating a selected one of a plurality of video sources;

timing generator means for providing display and source control timing signals, said timing generator means including a portion of said video source selecting means for providing different timing signals in response to the selection of different sources;

serial, digital memory means responsive to said timing generator means for storing signals;

input means including a portion of said video source selecting means and responsive to said timing generator means for providing to said serial memory signals relating to the video input of a selected one of the video sources;

a signal CRT display means having beam deflection and video intensity control means;

sweep generating means responsive to said timing generator means for providing at least a pair of sweep defining beam deflection signals to said display means, said sweep generating means including a plurality of different sweep generation circuits for each beam deflection control input signal required by said display means;

said sweep generating means including a portion of said video source selection means for providing different sweeps to said display means in dependence upon the nature of the selected one of the video sources; and

means responsive to said timing generator means for providing video signals to said display means in response to signals from said memory means.

2. The display system according to claim 1 additionally comprising:

memory input selection means interposed between said input means and the input of said memory means and including a portion of said video source selection means for alternatively causing the input of said memory means to be derived from the output thereof, thereby to recirculate the signals therein, or to be derived from said input means signals, thereto to update the video content of the signals stored in said memory means.

3. The display system according to claim 1 wherein said input means includes a data compression encode circuit and wherein said means providing video signals to said display means includes a data compression decode circuit operated in conjunction with said data compression encode circuit, thereby to provide data to said memory means in compressed fashion.

4. The display system according to claim 1 wherein said means providing signals to said display means includes a serial storage means for storing signals from said memory means and means responsive to said memory means and to said serial storage means for providing signals representing video intensity which is the average of the video intensity represented by signals from said memory means and signals from said storage means.

5. The display system according to claim 1 wherein said input means comprises input buffer storage means and a portion of said video source selection means and clock means responsive thereto for selectively operating said input buffer storage means at different video input rates commensurate with the selected one of the video sources.

6. The display system according to claim 1 adapted for use with a radar video source and a TV video source wherein said sweep generating means includes means to provide TV raster beam deflection signals or radar-format beam deflection signals in dependence upon the setting of said video source selection means.

7. The display system according to claim 6 including means providing horizontal synch and video blank signals for use by said TV source.

8. The display system according to claim 6 adapted for use with a complete TV video source that provides horizontal synch and vertical blank signals, and wherein said timing generator means includes means synchronized with said vertical blank signals for providing clocking signals to saiD memory means and sweep generation circuits are responsive to said horizontal synch and vertical blank signals for providing said TV raster beam deflection signals when said complete TV video source is selected by said video source selection means.