Passive aircraft proximity detector for use in highway vehicles

• US 5,270,706 A
• Filed: 07/15/1991
• Issued: 12/14/1993
• Est. Priority Date: 02/10/1989
• Status: Expired due to Fees

• Current Assignee: Smith, Dale T.
• Original Assignee: Smith, Dale T.
• Inventors: Smith, Dale T.
• Primary Examiner(s): Ng, Jin F.
• Assistant Examiner(s): Hofsass, Jeffery A.
• Application Number:
  US07/730,198
• Time in Patent Office: 883 Days
• Field of Search: 340/901, 340/945, 340/902, 340/903, 455/226, 455/227, 342/20, 342/30, 342/29
• US Class Current: 340/902
• CPC Class Codes: G01S 11/06 using intensity measurements
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005

Abstract

A passive aircraft proximity detector for use in highway vehicles. This invention includes a unique internal antenna (1) feeding a superheterodyne receiver (2). A novel reference system (3) provides phase synchronous local oscillator injection. A signal analysis system (4) determines the presence of a valid signal and activates a tracking indicator (5). The analysis system also provides range data to an indicator which displays the approximate range of the aircraft (6). A mutable timed audio alarm is also incorporated (7).

Claims

1. An aircraft proximity detector for use in a history vehicle, comprising:

a circuit board assembly, said assembly comprising two printed circuit boards, the first of said printed circuit boards having a receiver secured to an inside surface thereof and the second of said printed circuit boards having signal processor means secured to an inside surface thereof, said signal processor means comprising a frequency amplitude detector for passively detecting existing frequency emissions from aircraft flying in the vicinity of said vehicle and received by said receiver;

means for electrically connecting said assembly to a power source of said vehicle;

an antenna associated with said circuit board assembly; and

means for alerting an occupant of said vehicle that an aircraft has been detected based on an amplitude of said frequency emissions.

2. The detector of claim 7 wherein said receiver is superheterodyne.

3. The detector of claim 1 wherein said power source of said vehicle comprises a cigarette lighter plug connected in circuit with a vehicle battery.

4. The detector of claim 1, further comprising:

means for adjusting said receiver to a particular range of frequency emissions from said aircraft.

5. The detector of claim 1 wherein said antenna comprises two parallel conductor plates.

6. The detector of claim 5 wherein said conductor plates comprise the outside surfaces of said printed circuit boards.

7. The detector of claim 5 wherein said antenna further comprises a plurality of shorting bars connecting said plates.

8. The detector of claim 5 wherein said antenna comprises a waveguide antenna, a modified slot antenna and a transmission line radiator antenna.

9. The detector of claim 5 wherein said antenna comprises an omnidirectional scanner having full 360°

sensitivity.

10. The detector of claim 5 wherein critical dimensions of said plates are maintained on an order of one-half wavelength of a frequency range of said aircraft frequency emissions.

11. The detector of claim 1 wherein said circuit board assembly further comprises a filter, said filter comprising a microstrip structure, said microstrip structure comprising a band-pass filter at signal frequencies and a band-stop filter at image frequencies, and means for providing to said filter gain and impedance matching of a signal appearing at said antenna.

12. The detector of claim 11 wherein said circuit board assembly further comprises means for tuning said filter.

13. The detector of claim 11 wherein said means for providing gain and impedance matching comprises the positioning of surface mounted capacitors on said surface of said second printed circuit board, said positioning of said capacitors independently determining input and output impedances.

14. The detector of claim 1 wherein said circuit board assembly further comprises a double conversion system circuit.

15. The detector of claim 1, wherein said circuit board assembly further comprises a single conversion system circuit.

16. A passive aircraft proximity detector of ruse in a highway vehicle to detect aircraft, said detector comprising:

a circuit board assembly, said assembly comprising two printed circuit boards;

a superheterodyne receiver secured to a surface of a first of said printed circuit boards;

signal processor means secured to a surface of a second of said printed circuit boards;

an antenna self-contained and integral with said circuit board assembly for receiving existing frequencies emitted from aircraft, said signal processor means detecting an amplitude of said frequencies;

means for electrically connecting said detector to a power source of said vehicle; and

means in circuit relationship with said circuit board assembly for indicating that an aircraft has been detected based on said amplitude.

17. The detector of claim 16, further comprising:

means associated with said circuit board assembly to read out the approximate range of an aircraft from said vehicle based on said amplitude.

18. The detector of claim 16 wherein said means for indicating comprises an audio alarm, said alarm activated when said amplitude exceeds a predetermined level.

19. The detector of claim 17, further comprising:

means for manually adjusting a detection range.

20. The detector of claim 16 wherein said power source is a 12 volt DC source.

21. A aircraft proximity detector for use in a highway vehicle, comprising:

a compact case assembly, said assembly comprising a frequency receiver operating within a frequency range of 900 to 1300 megahertz to passively detect existing frequency emissions from aircraft within the detection range of said receiver, antenna means associated with said receiver, signal conversion circuit means for processing the frequency signal appearing at said antenna means and detecting an amplitude of said frequency signal, means associated with said signal conversion circuit means for alerting an occupant of said vehicle that an aircraft has been detected based on said amplitude, and means for electrically connecting said assembly to a power source of said vehicle.

22. The detector of claim 21 wherein said antenna means comprises a plate adjacent said receiver.

23. The detector of claim 21 wherein said antenna means comprises two parallel conductor plates.

24. The detector of claim 21 wherein said means for alerting an occupant of said vehicle comprises means for reading out an approximate distance of said aircraft from said vehicle based on said amplitude.

25. The detector of claim 21 wherein said means for alerting an occupant of said vehicle comprises an audio alarm, said alarm activated when said amplitude exceeds a predetermined level.

26. The detector of claim 25, further comprising:

means to deactivate said audio alarm without deactivating said detector.

27. The detector of claim 21, further comprising:

means for manually adjusting a detection range.

28. The detector of claim 21 wherein said detector is powered by a 12 volt DC source.

29. The detector of claim 21 wherein said signal conversion circuit means comprises a microstrip structure.

30. The detector of claim 21, further comprising:

a harmonically related local oscillator system operatively interconnected to said receiver.