Cavity axis orientation measurement device

• US 8,939,367 B2
• Filed: 03/14/2013
• Issued: 01/27/2015
• Est. Priority Date: 05/24/2012
• Status: Active Grant

• Current Assignee: Kenneth James Hintz
• Original Assignee: Kenneth James Hintz
• Inventors: Hintz, Kenneth James
• Primary Examiner(s): Kim, Ahshik
• Application Number:
  US13/827,230
• Publication Number:
  US 20140203080A1
• Time in Patent Office: 684 Days
• Field of Search: 235/404, 342/90, 342/192
• US Class Current: 235/404
• CPC Class Codes: F41G 3/08 with means for compensating for speed, direction, temperature, pressure, or humidity of the atmosphere measuring G01
• CPC Class Codes: F41G 3/147 based on detection of a firing weapon
• CPC Class Codes: G01S 13/347 using more than one modulation frequency
• CPC Class Codes: G01S 13/88 Radar or analogous systems specially adapted for specific applications electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00

Abstract

An apparatus for measuring the orientation of the longitudinal axis of a cavity comprising a signal receiver, a signal processor and analyzer and a cavity axis orientation analyzer. The signal receiver receives a reflected signal resulting from an interaction of multi-frequency irradiating signal(s) with at least one cavity. The irradiating signal may include an electromagnetic or acoustic signal above a cavity dependent cutoff frequency with a randomized or deterministic spectral component. The signal analyzer computes a power spectral density of the reflected signal. The local maxima of the power spectral density are identified and used to determine the cavity longitudinal axis orientation. The cavity may be the bore of a weapon.

Claims

1. An apparatus comprising:

a) a frequency selective signal receiver configured to receive at least one reradiated signal resulting from an interaction of an irradiating electromagnetic signal with a cavity, the irradiating electromagnetic signal including at least 3 frequency components above a cavity bore dependent cutoff frequency;

b) a signal processor configured to compute;

i) a power spectral density of the received reradiated signal, and,

ii) identify frequencies of largest local amplitude in the power spectral density;

c) an analyzer configured to relate at least one identified frequency of largest local amplitude with an orientation of the cavity longitudinal axis.

2. An apparatus comprising:

a) a signal receiver configured to receive at least one reradiated signal resulting from an interaction of at least one irradiating signal with at least one cavity;

b) a signal analyzer configured to compute at least one power spectral density of at least one of the at least one reradiated signal;

c) an analyzer configured to relate at least one of the frequencies of the at least one power spectral density with the orientation of the cavity axis.

3. An apparatus according to claim 2, wherein the at least one irradiating signal includes at least three frequency components.

4. An apparatus according to claim 2, wherein the at least one irradiating signal includes an electromagnetic signal.

5. An apparatus according to claim 2, wherein the at least one irradiating signal includes an acoustic signal.

6. An apparatus according to claim 2, wherein the analyzer employs a look-up table.

7. An apparatus according to claim 2, wherein the analyzer employs an analytic expression.

8. An apparatus according to claim 2, wherein the at least one irradiating signal includes a randomized spectral component.

9. An apparatus according to claim 2, wherein the at least one irradiating signal includes a spread spectrum irradiating signal.

10. An apparatus according to claim 2, wherein the at least one irradiating signal is generated using at least two non co-located radiators.

11. An apparatus according to claim 2, wherein the at least one irradiating signal originates from a location spatially distinct from the signal receiver.

12. An apparatus according to claim 2, wherein at least one reradiated signal is above a cavity dependent cutoff frequency.

13. An apparatus according to claim 2, wherein the cavity is a weapon bore.

14. An apparatus according to claim 2, wherein said apparatus is configured to determine at least one of the following:

a) the azimuth orientation relative to a frame of reference,

b) the elevation orientation relative to a frame of reference, or,

c) a combination of the above.

15. An apparatus according to claim 2, wherein the signal receiver is tunable to at least three frequencies.

16. An apparatus according to claim 2, wherein the measurement of the orientation of the longitudinal axis of the cavity is used to aim a weapon in the direction of at least one of the at least one cavity.