Patent US 4,536,747

Detectors (11a-d) are located at a plurality of locations and include go, no-go decision processor apparatus for subjecting outputs of the detectors (11a-d) to a go, no-go decision process. First signal generator and transmitter apparatus (12a-d) are interconnected to said go, no-go decision processor apparatus for generating and transmitting signals responsive to the output of said go, no-go decision processor apparatus, the signals being transmitted in a wave form configured to maximize differentiation from noise and interference. First data receiver apparatus (13) receives the signals from said first signal generator and transmitter apparatus (12a-d) and includes wave form recognition apparatus. A reprogrammable central processor apparatus (14) is interconnected to the data receiver apparatus (13) for providing action outputs representative of one or more actions to be taken in response to one or more signals received from the first data receiver apparatus (13). The reprogrammable central processor apparatus (14) provides for preselection of a false alarm rate based on action to be taken. The action outputs are provided to a second signal generator and transmitter apparatus (15) for transmission to a plurality of data receiver apparatus (16a-c) each interconnected to action devices (17a-c) for taking appropriate action in response to signals received from said second signal generator and transmission apparatus (15).