Coordinate store digital scan converter

Claim 2

In a radar system wherein it is desired to employ a scan converter for the purpose of improving the display of the targets detected by said radar system, and wherein said radar system provides digital data indicative of the coordinates of each target hit, the improvement in said scan converter comprising: cyclic memory means for storing the digital data coordinates for a plurality of target hits received from said radar system, said cyclic memory means including age code memory means for storing a code for each target hit digital data entered in said memory indicative that it is newly entered, and means for decrementing said age code for each target hit digital data each time it is cycled through said memory, means for comparing the coordinates of each new target hit digital data with the target hit digital data in said memory to determine if correlation exists and to provide a correlation signal indicative thereof, meaNs responsive to said correlation signal to prevent the storage of said new target hit digital coordinates in said memory, and means responsive to the absence of a correlation signal for storing said new target hit digital coordinates in said memory.

Claim 3

In a radar system as recited in claim 1 wherein there is included means for sensing the age code of the target hit data as it is transferred from output to input of memory and producing a signal when said age code attains a predetermined value, and means responsive to said age code and the absence of a correlation signal for enabling new target hit data to be stored in said memory in place of the target hit data whose age code has attained said predetermined value.

Claim 4

means for comparing the coordinates of each new target hit digital data with the target hit digital data in said memory to determine if correlation exists and to provide a correlation signal indicative thereof, and including: 2a. means for establishing a predetermined range of target hit digital coordinates for target hit digital coordinates in memory which is to be compared with said new target hit digital coordinates, said means for establishing a predetermined range of target hit digital coordinates including: 2a1. means for establishing incremental target hit digital azimuth, range and elevation coordinates, 2a2. means for combining said incremental target hit digital azimuth, range and elevation coordinates with corresponding target hit digital azimuth, range and elevation coordinates derived from said memory to produce incremented target hit digital azimuth, range and elevation coordinates, 2a3. first comparator means to which said new target hit digital azimuth, range and elevation coordinates and said incremented target hit digital azimuth, range and elevation coordinates are applied to produce a first output when said incremented target hit digital azimuth, range and elevation coordinates are all less than said corresponding new target hit digital azimuth, range and elevation coordinates, 2a4. second comparator means to which said new target hit digital azimuth, range and elevation coordinates and said target hit digital azimuth, range and elevation coordinates derived from said memory produce a second output indicative that said target hit digital azimuth, range and elevation coordinates derived from memory are all greater than said new target hit digital data, and 2a5. means responsive to said first and second outputs to produce said correlation signal, and

Claim 5

means for comparing the coordinates of each new target hit digital data with the target hit digital data in said memory to determine if correlation exists and to provide a correlation signal indicative thereof, and including: 2a. means for establishing a predetermined range of target hit digital coordinates for target hit digital coordinates in memory which is to be compared with said new target hit digital coordinates, said means for establishing a predetermined range of target hit digital coordinates including: 2a1. means for establishing incremental target hit digital azimuth, range and elevation coordinates, 2a2. means for combining said incremental target hit digital azimuth, range and elevation coordinates with corresponding target hit digital azimuth, range and elevation coordinates derived from said memory to produce incremented target hit digital azimuth, range and elevation coordinates, 2a3. first comparator means to which said new target hit digital azimuth, range and elevation coordinates and said incremented target hit digital azimuth, range and elevation coordinates are applied to produce a first output when said incremented target hit digital azimuth, range and elevation coordinates are all less than said corresponding new target hit digital azimuth, range and elevation coordinates, 2a4. second comparator means to which said new target hit digital azimuth, range and elevation coordinates and said target hit digital azimuth, range and elevation coordinates derived from said memory produce a second output indicative that said target hit digital azimuth, range and elevation coordinates derived from memory are all greater than said new target hit digital data, and 2a5. means responsive to said first and second outputs to produce said correlation signal, and

Claim 6

In a radar system wherein it is desired to employ a scan converter for the purpose of improving the display of the targets detected by said radar system, and wherein said radar system provides digital data indicative of the coordinates of each target hit, said coordinates including azimuth, range and elevation, the improvement in said scan converter comprising:

Claim 7

In a radar system wherein it is desired to employ a scan converter for the purpose of improving the display of the targets detected by said radar system, and wherein said radar system provides digital data indicative of the coordinates of each target hit, said coordinates including azimuth, range and elevation, the improvement in said scan converter comprising:

Claim 8

means for comparing said range of target hit digital coordinates with said new target hit digital coordinates and producing said correlation signal whenever said new target hit digital coordinates falls within said range,

Claim 9

means for comparing said range of target hit digital coordinates with said new target hit digital coordinates and producing said correlation signal whenever said new target hit digital coordinates falls within said range,

Claim 10

means responsive to said correlation signal to prevent the storage of said new target hit digital coordinates in said memory, and

Claim 11

means responsive to said correlation signal to prevent the storage of said new target hit digital coordinates in said memory, and

Claim 12

In an aircraft radar system wherein it is desired to employ a scan converter for the purpose of improving the display of the targets detected by said radar system and wherein said radar system provides digital position coordinates indicative of each target hit, the improvement in said scan converter comprising: cyclic memory means including means for storiNg the digital position coordinates for a plurality of target hits received from said radar system, means for generating an age code for each new target hit to be stored in said cyclic memory means, means for entering an age code into said cyclic memory means together with each new target hit being stored, means to periodically update said age code for each target hit stored in memory, means in said display responsive to said age code for establishing the brightness of the target hit displayed in accordance with its age code, a source of new target hit position coordinates, means for comparing new target hit position coordinates with all of the target hit position coordinates in said cyclic memory means for determining whether or not correlation exists and producing a correlation signal when it is established, means responsive to said correlation signal for storing an indication of correlation in said cyclic memory means for identifying the target hit for which correlation has been established, means for indicating when all of the target hit position coordinates in said cyclic memory means has been compared for correlation and producing a correlation completed signal indicative thereof, and means responsive to a correlation signal and a correlation completed signal for calling for new target hit position coordinates to be compared with the position coordinates in said memory.

Claim 13

In an aircraft radar system wherein it is desired to employ a scan converter for the purpose of improving the display of the targets detected by said radar system and wherein said radar system provides digital position coordinates indicative of each target hit, the improvement in said scan converter comprising: cyclic memory means including means for storiNg the digital position coordinates for a plurality of target hits received from said radar system, means for generating an age code for each new target hit to be stored in said cyclic memory means, means for entering an age code into said cyclic memory means together with each new target hit being stored, means to periodically update said age code for each target hit stored in memory, means in said display responsive to said age code for establishing the brightness of the target hit displayed in accordance with its age code, a source of new target hit position coordinates, means for comparing new target hit position coordinates with all of the target hit position coordinates in said cyclic memory means for determining whether or not correlation exists and producing a correlation signal when it is established, means responsive to said correlation signal for storing an indication of correlation in said cyclic memory means for identifying the target hit for which correlation has been established, means for indicating when all of the target hit position coordinates in said cyclic memory means has been compared for correlation and producing a correlation completed signal indicative thereof, and means responsive to a correlation signal and a correlation completed signal for calling for new target hit position coordinates to be compared with the position coordinates in said memory.

Claim 14

In an aircraft radar system as recited in claim 4 wherein said source of new target hit digital position coordinates is said aircraft radar system, there is included a means to detect when the age code for a stored target reaches a predetermined age to produce an age signal indicative thereof, and means responsive to the absence of a correlation signal and the presence of a correlation completed signal and an age signal to store said new target hit data in the place of the target hit data in said cyclic memory the age of which is given by said age signal.

Claim 15

means responsive to the absence of a correlation signal for storing said new target hit digital coordinates in said memory.

Claim 16

means responsive to the absence of a correlation signal for storing said new target hit digital coordinates in said memory.

Claim 17

In an aircraft radar system as recited in claim 4 wherein said source of new target hit position coordinates is an IFF system.

Claim 18

In an aircraft radar system as recited in claim 4 wherein said means for comparing includes means for establishing whether or not correlation exists over a predetermined range of target hit digital position coordinates values.