04152693 is referenced by 67 patents and cites 5 patents.

A positional display system for visually indicating given geographical locations such as the position of motor vehicles such as police cars and/or the location of the occurrence of an incident warranting police attention. The system includes a display board having a row and column matrix of individual lights and a map of the local geographic area of concern overlaying the matrix so that each light represents a unique map section. Whenever a patrol car transmits its position to a central station or a remote alarm indicates the occurrence of a robbery or the like, information indicative of the row and column address of the given location and at least one instructional command for determining the light status are entered. The entered information is converted into binary numbers indicative of the row and column addresses and the converted binary numbers are temporarily stored. The stored numbers are compared with the output of a scanning counter. The comparator outputs are gated to enable the instructional command for determining the status of the lights to be entered into a memory whenever the entered row and column address is scanned by the counter. The scanning counter is also coupled to a row decoder which sequentially generates the series of individual row scan signals and to a column decoder which sequentially generates a series of column scan signals. These signals are gated with the output of the memory and used to address corresponding rows and columns of the matrix so that when each row and column light is addressed, its illumination status will be determined by the memory output in accordance with the instructional command. If the location of the police cars are entered with an instructional command specifying a steady light condition and the location of an incident is entered with an instructional command specifying a blinking light, the person observing a display board will observe the locations of all patrol cars as steady lights and the location of the incident as a blinking light and will be able to determine which car is closest to the location of the incident for facilitating command and control dispatching decisions and the like.

Title
Vehicle locator system
Application Number
5/790265
Publication Number
4152693
Application Date
April 25, 1977
Publication Date
May 1, 1979
Inventor
Charles S Ashworth Jr
Warren
MI, US
Agent
Charles P Padgett Jr
Assignee
Audio Alert
MI, US
IPC
G08G 1/12
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