Abstract:
The present invention relates systems and methods of electromagnetic protection for integrated video and electromagnetic detector security system equipment. A security system configured to be protected from electromagnetic events or attacks includes a quantity of video cameras and a quantity of electromagnetic event detectors disposed at a facility. The system also includes an electromagnetically-shielded cabinet containing computing equipment and a storage media. The electromagnetically-shielded cabinet is configured to receive data from each of the quantity of video cameras and electromagnetic detectors and store the data on the storage media, whereby, in the event of an electromagnetic event, information at the time of the event can be preserved on the storage media. Additionally, the electromagnetic detectors can trigger the video cameras to scan the surrounding area once an electromagnetic event has been detected such that images of suspicious vehicles, persons, packages or other items can be recorded for future forensic investigations.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority from U.S. Provisional Application No. 61/425,152, filed Dec. 20, 2010, the disclosure of which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to electromagnetic protection of security equipment. In particular, the present disclosure relates to electromagnetic protection for integrated video and electromagnetic detector security system equipment. 
     BACKGROUND 
     Exposure to electromagnetic fields can cause interference or damage to electrical equipment, causing that equipment to malfunction or rendering it nonoperational. For example, electrical equipment can be blown or otherwise fail in the event of a strong electromagnetic pulse or intentional electromagnetic interference event (EMP/IEMI). 
     EMP/IEMI events typically take one of two forms. First, high field events correspond to short-duration, high voltage events (e.g., up to and exceeding 100 kilovolts per meter), and typically are of the form of short pulses of narrow-band or distributed signals (e.g., in the frequency range of 14 kHz to 10 GHz). These types of events typically generate high voltage differences in equipment, leading to high induced currents and burnout of electrical components. Second, low field events (e.g., events in the range of 0.01 to 10 volts per meter) are indications of changing electromagnetic environments below the high field damaging environments, but still of interest in certain applications. 
     Existing systems are used to defeat a narrow range of threats. The protection schemes built into electronic systems are generally developed to address a certain possible issue, are not useful to address other electromagnetic interference issues. Although attempts have been made to “harden” or protect, certain military systems against these threats, many commercial electronic systems remain unprotected. However, these existing “hardening” solutions are cost-prohibitive to apply to a wide range of electronics, exposing critical assets to possible damage One such unaddressed concern is for example equipment that is designed for security systems at various facilities. 
     For these and other reasons, improvements are desirable. 
     SUMMARY 
     In accordance with the following disclosure, the above and other issues are addressed by the following: 
     In a first aspect, a security system configured to be protected from electromagnetic events includes a plurality of cameras and a plurality of electromagnetic event detectors disposed at a facility. The system also includes an electromagnetically-shielded cabinet containing computing equipment and a storage media. The electromagnetically-shielded cabinet is configured to receive data from each of the plurality of video cameras and electromagnetic detectors and store the data on the storage media, whereby, in the event of an electromagnetic event, video image information at the time of the event and for a period of time after the event can be preserved on the storage media. The capture of such video data can later be used for forensic investigations related to the IEMI or EMP attack. 
     In a second aspect, a security system for a facility configured to be protected from electromagnetic events includes a detection system configured to detect an electromagnetic event. The security system also includes a monitoring system coupled to the detection system; wherein upon detection of the electromagnetic event, the monitoring system is configured to scan an area around the facility, capture images, tag the images, and store the images in a storage media. 
     In another embodiment of the present invention, a method of securing a facility against an electromagnetic event includes: monitoring the facility with a plurality of cameras disposed at the facility, detecting an electromagnetic event with a plurality of electromagnetic detectors disposed at the facility, and storing data in the system in a storage media. If the plurality of cameras are electromagnetic shielded and electrically filtered, the method also includes: scanning a first area around the facility, capturing images of the area around the facility, tagging the images, storing the images in the storage media, and reviewing the images after the event. The method also includes reviewing the data and images after the electromagnetic event. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic block diagram of an electromagnetically-protected security system installed at a facility, according to a possible embodiment of the present disclosure; 
         FIG. 2A  is an example embodiment of an antenna useable to detect high field pulses for use in a detector in the electromagnetically-protected security system of  FIG. 1 ; 
         FIG. 2B  is another example embodiment of an antenna useable to detect high field pulses for use in a detector in the electromagnetically-protected security system of  FIG. 1 ; 
         FIG. 3  is an example schematic depiction of an example embodiment of an antenna structure useable in connection with a detector in the electromagnetically-protected security system of  FIG. 1 ; 
         FIG. 4  is a front view of a schematic block diagram of an example embodiment of an electromagnetically shielded camera for use in the electromagnetically-protected security system of  FIG. 1 ; 
         FIG. 5  is a side cross-sectional schematic block diagram view of the electromagnetically shielded camera of  FIG. 4 . 
         FIG. 6  is a flow chart illustrating a method of securing a facility against an electromagnetic event, according to one possible embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments of the present invention will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the invention, which is limited only by the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the claimed invention. 
     In general the present disclosure relates to methods and systems for protection of security systems from various electromagnetic interference events, including Electromagnetic Pulse, Intentional Electromagnetic Interference (EMP/IEMI) threats, or any other electromagnetic event having an amplitude and frequency capable of damaging building electrical systems data centers and/or electronic equipment. In one embodiment, the present invention uses an EMP/IEMI protected camera, EMP/IEMI detectors, and an EMP/IMEI shielded and filtered cabinet for protecting video and detector data storage. 
     The logical operations of certain aspects of the disclosure described herein are implemented as: (1) a sequence of computer implemented steps, operations, or procedures running on a programmable circuit within a computer, and/or (2) a sequence of computer implemented steps, operations, or procedures running on a programmable circuit within a directory system, database, or compiler. 
     Referring now to  FIG. 1 , a schematic block diagram is shown of an electromagnetically-protected security system  100  installed at a facility  110 , according to a possible embodiment of the present disclosure. The facility  110  in this embodiment includes buildings  112 ,  114 . However, the facilities could be a production yard, a military operation or other type of facility. 
     In the embodiment shown, one or more video cameras  102  and electromagnetic detectors  104  are positioned around the facility  110  on the buildings  112 ,  114 . In other embodiments, the facility  110  can include more or less than two buildings and/or structures and/or operations. 
     The one or more video cameras  102  and electromagnetic detectors  104  can be placed throughout the facility  110 , including the exterior of the buildings  112 ,  114 , as well as the interior of the buildings  112 ,  114 . In certain embodiments, the video cameras  102  can be electromagnetically protected video cameras, such as are disclosed in copending U.S. Provisional Application No. 13/289,849, and entitled “Electromagnetically Shielded Video Camera and Shielded Enclosure for Image Capture Devices,” the disclosure of which is hereby incorporated by reference in its entirety. In still further embodiments, the electromagnetic detectors  104  can be any of a number of types of detectors of electromagnetic events; example detectors useable in the system  100  are disclosed in U.S. patent application Ser. No. 12/906,902, filed Oct. 18, 2010, and entitled “Electromagnetic Field Detection Systems and Methods,” the disclosure of which is hereby incorporated by reference in its entirety. 
     In use, video data captured by the video cameras  102  is streamed, for example via a protected electrical data cable or a fiber cable, to a storage media within an EMP/IEMI protected cabinet  106  containing computing equipment. Likewise, any signals received from the electromagnetic detectors  104  are streamed into this same EMP/IEMI protected cabinet  106 . Should the facility  110  experience either an EMP or IEMI pulse, signals would be transmitted to the computing equipment and storage media, and optionally the incident would immediately give a warning signal to security officers at the facility  110 . In certain embodiments, any video data stored in the media would also be tagged as to the time of the incident, either by the video cameras  102  or a computing system within the cabinet  106 . Security personnel would then be able to review the video information to identify the source of the electromagnetic event, specifically including suspect vehicles, persons, packages, or other items that might be related to the cause of the incident. 
     In a second embodiment, one or more video cameras  102  can be a non-EMP/IEMI protected camera, which would record and transmit video up until an EMP/IEMI event. At the time of such an event, the camera would likely be damaged; however, any stored video up until the time of the event could be used as forensic evidence to determine the identity of a vehicle, person or packages that may have been involved in the EMP/IEMI attack. Other embodiments may include a combination of shielded and unshielded cameras wherein those cameras that are shielded would continue scanning upon detecting an electromagnetic event. In yet further embodiments, the cameras  102  can be still or infrared cameras. 
     The detectors  104  can take any of a number of forms. In some embodiments, the detectors  104  can be a standalone high field or low field electromagnetic event detector. In such embodiments, the detectors  104  can optionally also include other sensors, such as temperature, carbon monoxide, carbon dioxide, smoke, fire, radiation, or chemical sensors as well. Additionally, one or more different types of detectors can be used at a single facility  102 . 
     In some embodiments, the detectors  104  are communicatively connected to a detection system  108 , which in various embodiments can be a centrally-located, shielded computing system configured to receive signals from the detectors  104 . The detection system  108  can analyze the signals received from the detectors and, based on one or more different types of calculations (as described below), can detect the presence of a high field or low field electromagnetic event, such as an EMP/IEMI event. The detection system  108  can also communicate status information regarding electromagnetic events, or observed electrical field readings, to a remote system (not shown) such as a data archival system or for purposes of alarming to a remote monitoring system, or for forensic information. The detection system  108  may be positioned at any location around the facility  110  that enables communication with the detectors  104 , including within the cabinet  106 , or on the exterior or interior of buildings  112 ,  114 . 
     Referring now to  FIGS. 2A and 2B , two example antennas  200 ,  220  respectively, for use in the detectors  104  to detect high-field pulses, according to a possible embodiment of the present disclosure, are illustrated. 
     The antennas  200 ,  220  are, in the embodiments shown, a shielded loop magnetic antenna. For example, in  FIG. 2A , the antenna  200  is a generally circular loop antenna having a loop of approximately ¼ inch or less in diameter, and including shielding (e.g., a metal sheath); in  FIG. 2B , the antenna  220  is a generally rectangular loop antenna having size of approximately ¼ inch in length. Each antenna includes shielding  202 ,  222  (represented by solid lines) which extends around each loop  204 ,  224  (illustrated using dotted lines), and effectively limits induction of an electrical field on the antenna, while making the loops  204 ,  224  susceptible to magnetic fields. Each antenna also includes an exposed gap portion  206 ,  226 , respectively, at which the magnetic field is induced. In particular embodiments, the antennas  200 ,  220  can be high field self-integrating B dot antennas. Other embodiments are possible as well. 
     In the embodiments shown, the antennas  200 ,  220  are configured to output voltages that are directly proportional to the electrical field amplitude that corresponds to the component of the observed magnetic field at a given frequency at the antenna. In certain embodiments, the antennas  200 ,  220  are configured to output voltages of zero to five volts, depending upon the field strength of the electrical field observed (as inferred from the observed magnetic field strength). Preferably, the antennas  200 ,  220  have tailored inductance and resistance values to result in output of such voltages and has a sufficiently fast (nanosecond range) response times to detect EMP/IEMI pulse events. In certain embodiments, the antennas  200 ,  220  have output amplitudes that in combination with an equalizer are independent of frequency, at least over a predetermined frequency range. In certain embodiments, that frequency range can include about 200 MHz to about 10 GHz; in other embodiments, the frequency range can extend from about 10 MHz to about 10 GHz. 
     Additionally, although the antennas  200 ,  220  are described as being approximately ¼ inch in diameter, other sizes or dimensions of antennas are possible as well. By changing the size of the antennas  200 ,  220 , different ranges of frequencies can be detected. The ¼ inch or less antennas described herein are intended to be responsive across the range of frequencies in which EMP/IEMI events occur, as described in the preceding paragraph. 
     In use, the antennas  200 ,  220  can each be used on the detectors  104  to obtain measurements of far field magnetic field measurements to infer electric field intensity, and therefore to detect electromagnetic pulses or other electromagnetic events in the security system  100 , as previously described. When placed in a far field from the electromagnetic radiation source (e.g., spaced such that a radiation source is more than several wavelengths away from the antenna), the magnetic field strength detected by the antenna,            , is directly correlated to the electric field strength component Ē by the impedance of free space, approximately 377Ω. Through use of the antennas  200 ,  220 , electrical field strengths can be inferred for fields of very high intensity, including fields in the range of 100 volts per meter to 100,000 volts per meter or more without additional attenuation of the inbound signal.
     Referring now to  FIG. 3 , an example of an antenna structure  300  useable as a detector  104  in the security system  100  is illustrated. In this embodiment, three shielded loop magnetic antennas  302   a - c  are used, and each extends along an axis in a direction normal to the other two antennas, and has a loop that is oriented in a direction normal to the orientation of the other two loop antennas. The antennas  302   a - c  are mounted in this embodiment to a cubic or rectangular base  304 , which can also house either one or more standard modules or other circuits for processing signals received at the antennas, or forwarding those signals to such circuits for processing. In alternative embodiments, the antenna structure  300  may use varying numbers of shielded loop magnetic antennas, including one or more than three. The antenna structure  300 , when used in the detectors  104 , is capable of detecting an electromagnetic event. At such time, the detectors  104  transmits signals to the detection system  108  which analyzes the signals and may communicate the presence of an electromagnetic event to a remote location. 
     Referring now to  FIGS. 4-5 , an electromagnetically shielded camera  400 , one embodiment of the cameras  102 , is shown.  FIG. 4  illustrates a front view of a schematic block diagram of the electromagnetically shielded camera  400 , while  FIG. 5  illustrates a side cross-sectional schematic view of the camera  400  along an axis “A” depicted in  FIG. 4 . 
     In the embodiment shown, the electromagnetically shielded camera  400  includes a waveguide beyond cutoff  402  mounted in a wall of an enclosure  404 . Specifically, the arrangement  400  includes a waveguide  402 , usually comprised of small, thin-walled conductive hexagonal or other shape cells  403 , mounted in a wall of an enclosure  404  which encloses and shields a camera  406  and associated lens  408 . 
     The enclosure  404  is generally configured to be an electromagnetically-shielding enclosure, capable of shielding an interior volume  410  of the enclosure from undesirable electromagnetic signals (e.g., electromagnetic signals exceeding a particular amplitude and frequency). In various embodiments, the enclosure  404  can be constructed from conductive materials, such as a metal (e.g., sheet metal or aluminum) having a thickness generally sufficient to attenuate electromagnetic signals to acceptable levels. Although in the embodiment shown the enclosure  404  is generally rectangular, it is understood that the enclosure  404  could be any of a variety of shapes. In an example embodiment, the enclosure  404  provides about 70 dB or more of attenuation. However, in alternative embodiments, other levels of attenuation could be provided as well. 
     In the embodiment shown, a frame  405  can be used to mount the waveguide beyond cutoff  402  to the enclosure  404 . In various embodiments, the frame can provide a sealing connection to the enclosure  404 , for example using an electromagnetically-shielded gasket arrangement or other arrangements. 
     In some embodiments, the camera  406  may include a shielded window or lens configured to prevent electromagnetic energy from entering the camera enclosure  404 . Such a shielded window or lens may include a conductive coating suitable for rejecting electromagnetic radiation from damaging the various electrical components of the camera  406 . Details regarding such an embodiment are disclosed in U.S. patent application Ser. No. 13/289,861, the disclosure of which is hereby incorporated by reference in its entirety. Additional details of a shielded camera, such as camera  406 , are discussed in U.S. patent application Ser. No. 13/289,849, the disclosure of which was previously incorporated by reference. 
     As illustrated in further detail in  FIG. 5 , the camera  406  can be, in various embodiments, any of a variety of camera types, such as a still camera or video camera or infrared camera, and can be configured for use in the security system  100 . In the embodiment shown, the camera  406  is powered by an external power signal line  412  which enters the enclosure  404  at an electrical filter  414 . Various types of electrical filters could be used, such as a low-pass, band pass, or spark gap type filter; generally, the filter is selected to be capable of receiving a power signal (e.g., either a direct current signal having a predetermine voltage and amplitude, or an alternating current signal having an expected frequency and amplitude). The filter can be configured to prevent signals over a predetermined amplitude or frequency (e.g., within the range of typical EMP/IEMI events up to 10 GHz) from entering the enclosure via the power signal line  412 . 
     The lens  408  can be any of a variety of types of automatically focusing or manually focused lenses. Generally, the lens  408  will have a focus length at a distance greater than the distance at which the waveguide beyond cutoff  402  is placed, such that the camera  406  does not focus on the waveguide, but instead focuses “through” the waveguide beyond cutoff on objects external to the enclosure  404 . That is, the camera lens  408  can be selected, specific focal length and f-stop, such that the camera  406  focuses on objects in the far field. Hence the honeycomb waveguide material of the cells  403 , which is in the near field, will be outside the depth of focus of the camera, and obscuration will be minimized. In this way, the imaging quality of the camera image will be retained with minimal distortion. In the embodiment shown, because the camera  406 , lens  408  and waveguide  402  are mounted in alignment, viewing through the honeycomb waveguide cells  403  is nearly unobstructed. 
     In certain embodiments, an additional optical grade lens or window could optionally be located in “front” of the waveguide beyond cutoff  402  (external to the enclosure  404 ) to protect the camera and wave guide from exposure to environmental conditions. 
       FIG. 6  is a flowchart of a method  600  for capturing electromagnetic detector and camera data at a facility in the event of an electromagnetic attack. In some embodiments, the methods and systems can be performed at least in part using (1) electromagnetic detectors, (2) shielded or unshielded video cameras, (3) a shielded storage cabinet, and (4) a microprocessor or computing device communicatively connected to the detectors, cameras, and shielded cabinet. 
     In the embodiment shown, the method is initiated at a start operation  602 , which corresponds to initial setup of one or more detectors, video cameras, and shielded cabinets at a facility or other location to be monitored, as well as connection of the one or more detectors to other computing devices configured to coordinate detection and analysis of high field and/or low field electromagnetic events, such as those described above. 
     A field monitoring operation  604  corresponds to scanning of the facility with the use of the cameras and detecting a field at an antenna of the electromagnetic (EM) detectors. The monitoring operation  604  can correspond to detection of one or more directional components of a magnetic field using one or more oriented shielded loop electromagnetic antennas, as described above in  FIGS. 2A, 2B, and 3 . 
     An electromagnetic event determination operation  606  determines whether an electromagnetic event has occurred. Typically the electromagnetic event determination operation  606  includes sampling a peak value detected using a standard circuit module and associated microprocessor, and performing one or more additional operations on that sample to determine whether a high or low field event occurs. For example, in the case of a high field event, the peak value may be summed or otherwise combined with other inferred electrical field values (e.g., by using the square root of a sum of squares) to arrive at an overall electromagnetic field value, and comparing that value to a preset known threshold, over which it is assumed that a high field event has occurred. In a further example, for low field events, the detected peak value can be directly compared to a known threshold value, and based on that comparison the existence of a low field event can be determined. 
     If no high or low field event is detected, operational flow can return to the field monitoring operation  604  to continue monitoring the electromagnetic fields present at the detector and scanning the facility with the cameras. However, if a high or low field event is detected, operational flow proceeds to a data storing operation  608 , which stores any data (including field values and times at which the filed values were captured) obtained during the field monitoring operation  604 . In some embodiments, the existing data will be transmitted to a shielded storage cabinet having a storage media in which the data can be stored and secured for later viewing. In some embodiments, the data storing operation  608  will also simultaneously include communicating the event to a remote location to report the incident. In other embodiments, communication of the event may occur at a later time. 
     A shielded-camera determination operation  610  determines whether the cameras used in the security system include an electromagnetic shielding. If it is determined that they do, a scanning operation  612  begins. Typically, the scanning operation  612  includes scanning the facility through the use of the cameras for unusual activity on or around the facility. A capture image operation  614  collects image data of the facility. The type of image captured can vary based on the type of cameras used. For example, in some embodiments, the images may be still, video, or infrared images. After the images are captured, a tagging image operation  616  tags the data with relevant information, such as, for example, field values and times at which the filed values were captured. In other embodiments, various other tags may exist. A storing image operation  618  stores the newly captured images for later review. In some embodiments, the images will be stored in a storage media located within the shielded cabinet so that the images will be protected from destruction by the electromagnetic event. 
     Whether the shielded camera determination operation  610  determines that the cameras are shielded or not, the operational flow eventually can continue to a reviewing data operation  620 . The reviewing data operation  620  includes reviewing the stored data after the electromagnetic event. Specifically, the data can be reviewed to identify the source of the electromagnetic event, including suspect vehicles, persons, packages, or other items that might be related to the cause of the incident. In some embodiments, this step is implemented by security personnel. An end operation  622  corresponds to completed detection after a desired (e.g. preset or undetermined) amount of time after the electromagnetic event. 
     The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.