RELATING TO SCANNERS

• US 20100039309A1
• Filed: 09/07/2007
• Published: 02/18/2010
• Est. Priority Date: 09/07/2006
• Status: Active Grant

• Current Assignee: BAE Systems Plc, MBDA UK Ltd. (MBDA SAS)
• Original Assignee: BAE Systems Plc
• Inventors: Rowatt, Charles Anthony, Carter, Christopher Ralph
• Granted Patent: US 8,674,875 B2
• Time in Patent Office: Days
• US Class Current: 342/22
• CPC Class Codes: G01S 13/003 Bistatic radar systems; Multistatic radar systems
• CPC Class Codes: G01S 13/04 Systems determining presence of a target based on relative movement of target G01S13/56
• CPC Class Codes: G01S 13/34 using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
• CPC Class Codes: G01S 13/426 Scanning radar, e.g. 3D radar G01S13/66 takes precedence
• CPC Class Codes: G01S 13/86 Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
• 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
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 7/026 involving the transmission of elliptically or circularly polarised waves
• CPC Class Codes: G07C 9/10 Movable barriers with registering means

Abstract

The invention provides a security scanner that produces a radar profile of a clothed person or another object such as a bag carried by a person at a distance and does not require close proximity of the person or object to the scanner itself. The scanner includes a millimetre wave antenna system optimised for short-range active imaging and arranged to provide rapid high-resolution images of an object or person of interest and processing means for resolving the images so as to detect the presence of predetermined objects. The processing means preferably includes means for comparing contrasts in reflectivity in the scanned images with predetermined expected values from skin and light clothing. The processing means may also include means for detecting predetermined behavioural or physical traits such as the effect on gait on carried weighty objects or stiff structures strapped to the person from the images of a scanned object or person. The scanner may be incorporated within a turnstile access arrangement.

Claims

1. A security scanner, the scanner comprising a millimetre wave radar arrangement comprising an antenna system optimised for short-range active imaging and arranged to provide rapid high-resolution images of an object or person of interest and processing means for resolving the images so as to detect the presence of predetermined objects.

2. A security scanner according to claim 1, wherein the antenna system utilises circular polarised radiation.

3. A security scanner according to claim 1, wherein the antenna system comprises a single mono-static antenna element.

4. A security scanner according to claim 1, wherein the antenna system comprises two mono-static antenna elements arranged as a single bi-static antenna.

5. A security scanner according to claim 1, wherein the antenna system comprises at least two mono-static antenna elements arranged as both a dual mono-static antenna and a bi-static antenna.

6. A security scanner according claim 1, wherein the antenna system utilises a quasi-optical lens system to collimate the transmitted radar waves and to perform polar analysis of the returned radar waves.

7. A security scanner according to claim 1, wherein the antenna system includes a frequency modulated continuous wave (FMCW) transmitter.

8. A security scanner according to claim 1, wherein the antenna system includes an interrupted frequency modulated (FMICW) transmitter that is arranged to reject unwanted signals from objects at a range greater than the object of interest.

9. A security scanner according to claim 7, comprising a low power transmitter.

10. A security scanner according to claim 1, further comprising a plurality of synchronised scanning mirrors arranged to scan in the azimuth plane

11. A security scanner according to claim 1, further including additional sensors for providing additional output data, the images from the antenna system being fused with that of additional sensors.

12. A security scanner according to claim 1, wherein the additional sensors include one or more of:

passive millimetre-wave system, passive infrared system or high definition TV.

13. A security scanner according to claim 1, wherein the processing means includes means for comparing contrasts in reflectivity in the scanned images with predetermined expected values.

14. A security scanner according to claim 1, wherein the processing means includes means for detecting predetermined behavioural or physical traits from the images of a scanned object or person.

15. A turnstile access arrangement including at least one security scanner according to claim 1.

16. A turnstile access arrangement according to claim 15, further including ticketing or personal identification tag (PIT) systems.

17. A turnstile access arrangement according to claim 15, comprising a plurality of scanning channels, each incorporating a security scanner arranged to scan a person or object passing through the channel.

18. A turnstile access arrangement according to claim 15, further including at least one of:

a local area network, intranet or the internet, arranged to provide command and control functionality to a wider network enabled security infrastructure.