Aircraft security system
First Claim
1. An aircraft signalling system comprising:
- a central control unit including an onboard computer and a dc power source;
one or more cluster controllers, each remotely located from said central unit and including a microprocessor;
a plurality of sensors associated with and controlled by each cluster controller;
a two-wire bus connecting said central unit and said cluster controllers, said bus carrying dc operating power from said power source to said cluster controllers and said plurality of sensors and carrying digital data signals in both directions between said onboard computer and said cluster controllers, said data signals including positive-going transitions and negative-going transitions between binary logic levels;
said central control unit further including first interface means for interfacing said dc power and digital data signals to said two-wire bus; and
said cluster controllers each further including second interface means for interfacing said dc power and digital data signals to said two-wire bus, said first interface means and said second interface means each including means responsive to said positive-going transitions and said negative-going transitions in digital data signals received on said bus for reconstructing said digital data signals.
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Accused Products
Abstract
An aircraft security system includes a central control unit, several remotely located cluster controllers and a plurality of intrusion sensors associated with and controlled by each cluster controller. A two-wire bus carries power from the central control unit for operating each of the cluster controllers and the sensors, and carries data signals in both directions between the central control unit and the cluster controllers. The two-wire bus reduces weight and installation costs. The system includes an initial calibration mode wherein sensor type information and sensor parameters are sent from the central control unit to each cluster controller. The signal strength from each sensor is then measured and stored in the central control unit. During later operation, the sensor signal strengths are measured and compared with the initial values. If a trouble condition is detected, appropriate corrective action is taken. One corrective action includes varying the transmitted energy until the sensor signal strength is within a prescribed range.
71 Citations
25 Claims
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1. An aircraft signalling system comprising:
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a central control unit including an onboard computer and a dc power source; one or more cluster controllers, each remotely located from said central unit and including a microprocessor; a plurality of sensors associated with and controlled by each cluster controller; a two-wire bus connecting said central unit and said cluster controllers, said bus carrying dc operating power from said power source to said cluster controllers and said plurality of sensors and carrying digital data signals in both directions between said onboard computer and said cluster controllers, said data signals including positive-going transitions and negative-going transitions between binary logic levels; said central control unit further including first interface means for interfacing said dc power and digital data signals to said two-wire bus; and said cluster controllers each further including second interface means for interfacing said dc power and digital data signals to said two-wire bus, said first interface means and said second interface means each including means responsive to said positive-going transitions and said negative-going transitions in digital data signals received on said bus for reconstructing said digital data signals. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 20, 21, 22)
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10. A signalling system comprising:
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a central control unit including a computer and a dc power source; one or more cluster controllers, each remotely located from said central unit and including a microprocessor; a plurality of sensors associated with and controlled by each cluster controller; a two-wire bus connecting said central unit and said cluster controllers, said bus carrying dc operating power from said power source to said cluster controllers and said plurality of sensors and carrying digital data signals in both directions between said computer and said cluster controllers, said data signals including positive-going transitions and negative-going transitions between binary logic levels; said central control unit further including first interface means for interfacing said dc power and digital data signals to said two-wire bus; and said cluster controllers each further including second interface means for interfacing said dc power and digital data signals to said two-wire bus, said first interface means and said second interface means each including means responsive to said positive-going transitions and said negative-going transitions in digital data signals received on said bus for reconstructing said digital data signals.
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11. A measuring and signalling system comprising:
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a central control unit including a computer and a dc power source; one or more cluster controllers, each remotely located from said central unit and including a microprocessor; a plurality of sensors associated with and controlled by each cluster controller; a two-wire bus connecting said central unit and said cluster controllers, said bus carrying dc operating power from said power source to said cluster controllers and said plurality of sensors and carrying digital data signals in both directions between said computer and said cluster controllers, said data signals including positive-going transitions and negative-going transitions between binary logic levels; said central control unit further including first interface means for interfacing said dc power and digital data signals to said two-wire bus; and said cluster controllers each further including second interface means for interfacing said dc power and digital data signals to said two-wire bus, said first interface means and said second interface means each including means responsive to said positive-going transitions and said negative-going transitions in digital data signals received on said bus for reconstructing said digital data signals. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 23, 24, 25)
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Specification