Patent Publication Number: US-11049379-B2

Title: Marker system with zone notification

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation in part of U.S. patent application Ser. No. 15/091,596 filed Apr. 15, 2016, which claims the benefit of U.S. provisional application No. 62/163,104 filed on May 18, 2015, the disclosure of all the above are hereby incorporated by reference. 
    
    
     FIELD 
     This invention relates to the field of marker systems, and more particularly to a personnel/combatant identification/marker light optionally having “Identification Friend or Foe” (IFF) interrogation and/or munitions-targeting acquisition and response capabilities. 
     BACKGROUND 
     Currently there are several marking/indicator devices that emit various wavelengths of light as needed. In many scenarios, specific situations require personnel/combatants to wear, carry, or mount multiple marking devices to their helmets, clothing, equipment, etc., to meet operational needs. For instance and in the past, military free fall parachuting performed at night often required the combatant carry a chemical light or single-use, single spectrum electronic equivalent for collision-avoidance while in free fall. Additionally, the combatant had to carry a white strobe light to meet FAA requirements for parachuting at night during training. Also, the combatant had to wear a multi-function visible and/or infrared helmet-mounted light to identify and mark personnel for command and control purposes once on the ground. Finally, for certain operations, the combatant had to wear or carry an IFF interrogation response device to signal back when interrogated or illuminated by friendly forces using handheld, weapon-mounted, aircraft, or vehicle-mounted infrared laser devices. 
     Multiple devices create a plethora of issues such as maintaining each device (e.g. fresh batteries for each operation, testing functionality before operations, etc.), and controlling the function of each device at various stages of the operation (e.g., changing from overt to covert operation, etc.). Further, the total weight of such devices and their respective battery packs as well real estate for each device (e.g., helmet space) is often an issue. 
     Single-purpose IFF interrogation response devices, including those integrated into patches that are attached by hook and loop material to the arm or shoulder exist, but the range of such, the directionality of such, and feedback flexibility from such are limited due to physical characteristics of such, limited acquisition and emission angles, and installation location constraints on the combatant. 
     In some scenarios, aircraft or ground-based targeting lasers are configured to illuminate a target or target area with a specific wavelength of laser radiation, often modulated with a secure code of the day, before using the reflections of such illumination to launch laser-guided munitions; in such cases it is important that forward-deployed combatants such as forward observers be alerted that they are being illuminated by such targeting lasers so as to initiate self-protection procedures including radio communication with the targeting aircraft crew or ground-based targeting laser operator. 
     In some scenarios, the combatant needs an indication regarding entering restricted or dangerous locations so as to not inadvertently enter into a target zone, a mine field, or a known enemy location. 
     What is needed is a single device that will provide a one or several marking capabilities as well as notifying when entering a restricted or dangerous location. 
     SUMMARY 
     In one embodiment, a helmet-mounted marker system is disclosed including one or more coordinates of one or more danger zones in digital format and a mechanism for periodically determining a location of the helmet-mounted marker system. From the location, another mechanism determines if the location of the helmet-mounted marker system is within any of the one or more danger zones. If the location of the helmet-mounted marker system is within any of the one or more danger zones, there is a mechanism to notify a wearer of the helmet-mounted marker system. 
     In another embodiment, a marker system is disclosed including an enclosure having a controller there within. A plurality of emitters are within the enclosure and are electrically interfaced to the controller such that, upon the controller initiating a flow of electric current though one or more of the emitters, the one or more of the emitters emit light. At least two detectors are within the enclosure and are electrically interfaced to the controller. The at least two detectors detect light of at least one specific wavelength and convert the light into an electrical signal that is received by the controller. Software stored on a non-transitory storage associated with the controller processes the electrical signal to determine if the incoming signal includes an Identification Friend or Foe (IFF) signal. Upon detecting the incoming Identification Friend or Foe (IFF) by the software, the software initiates flow of the electrical current through a first set of the emitters, emitting light of a first wavelength in a first predetermined pattern. One or more coordinates defining one or more danger zones and a global positioning receiver is interfaced to the controller. The software periodically receives a current location from the global positioning receiver and compares the current location to the one or more coordinates to determine if the marker system is within one of the one or more danger zones. If the marker system is within the one of the one or more danger zones, the software notifies of being within the one of the one or more danger zones (e.g. emits vibration). 
     In another embodiment, a marker system is disclosed including an enclosure having a controller located there within. An external processor-based device has a global position receiver (GPS). The external processor-based device has at least one set of coordinates defining at least one danger zone. The marker system has a plurality of light emitting diodes that are electrically interfaced to the controller and at least one photo detector that is/are electrically interfaced to the controller. The at least one photo detector is/are electrically interfaced to the controller positioned within the enclosure. A vibration device is electrically interfaced to the controller. Software stored on a non-transitory storage associated with the controller and running on the controller, processes an electrical signal from the at least one photo detector and detects if the incoming signals includes any of an incoming Identification Friend or Foe (IFF). Upon the software detecting the incoming Identification Friend or Foe (IFF) signal, the software provides electrical current in a first pattern to a first subset of the light emitting diodes to respond to the incoming Identification Friend or Foe (IFF). Second software is stored on a non-transitory storage associated with the external processor-based device. The second software periodically retrieves a current location from the global position receiver (GPS) and compares the current location with the at least one set of coordinates. If the current location is within the at least one set of coordinates, the second software transmits a signal from the external processor-based device to the controller. Responsive to receiving the signal from the external processor-based device, the first software running on the controller initiates operation of a vibratory device, causing the vibratory device to vibrate, thereby warning a user of the marker system that they are within one of the danger zones. 
     In another embodiment, a marker system is disclosed including at least one emitter. The emitter(s) emit light responsive to a flow of electrical current there through. The marker system includes a device for acquiring an incoming signal and a circuit for processing the incoming signal. The circuit for processing the incoming signal monitors the device for acquiring the incoming signal to determine if the incoming signal includes any of a plurality of incoming Identification Friend or Foe (IFF) and/or munitions targeting signals. The circuit emits one of a plurality of responses by sending electrical current through the emitter(s) based upon which of the plurality of incoming Identification Friend or Foe (IFF) interrogation and/or munitions targeting signals (hereinafter “IFF interrogation/targeting signals”) is detected by the means for processing. 
     In another embodiment, a marker system is disclosed including several emitters electrically interfaced to a controller such that, upon the controller initiating a flow of electric current though one or more of the emitters, the one or more of the emitters emit light. At least one detector is also electrically interfaced to the controller. The detector(s) detect light in of a specific wavelength and convert the light to an electrical signal that is received and understood by the controller. Software that is stored on a non-transitory storage associated with the controller monitors the at least one detector for any of a plurality of incoming IFF interrogation/targeting signals. Responsive to receiving and detecting any one of the plurality of incoming IFF interrogation/targeting signals from the at least one detector, the software initiates the flow of electric current through a selected set of the plurality of emitters. 
     In another embodiment, a marker system is disclosed including a vibration device, a switch, at least one light emitting diode, and at least one photo detector electrically interfaced to a controller. Software stored on a non-transitory storage associated with the controller determines a mode based upon signals from the switch. Upon the software detecting one of a plurality of incoming IFF interrogation/targeting signals from any of the at least one photo detectors, the software provides electrical current to a subset of the at least one light emitting diode to respond to the one of the incoming IFF interrogation/targeting signals, thereby the subset of the at least one light emitting diode emits light responsive to the software detecting the one of the incoming IFF interrogation/targeting signals. 
     In another embodiment, a marker system is disclosed including at least one emitter. Each of the at least one emitter emits the first light responsive to a flow of electrical current through that emitter. There is a device for acquiring an incoming signal and a circuit for processing the incoming signal. The circuit for processing the incoming signal monitors the device for acquiring the incoming signal to determine if the incoming signal includes an incoming IFF interrogation/targeting signal. The circuit emits a response when the circuit for processing detects the incoming IFF interrogation/targeting signal from the device for acquiring. 
     In another embodiment, a marker system is disclosed including a controller with a plurality of emitters electrically interfaced to the controller such that, upon the controller initiating a flow of electric current though one or more of the emitters, the one or more of the emitters emit light. There is also at least one detector electrically interfaced to the controller. The detector(s) are for detecting light in of a specific wavelength and converting the light to an electrical signal that is then received by the controller. Software is stored on a non-transitory storage associated with the controller. The software monitors the at least one detector for an incoming IFF interrogation/targeting signal and the software initiating the flow of electric current through a selected set of the plurality of emitters responsive to receiving the incoming IFF interrogation/targeting signal from the at least one detector. 
     In another embodiment, a marker system is disclosed including a controller having a first switch and a second switch electrically interfaced to the controller. The first switch for selectively chooses an operating function (e.g., specific emission wavelength, intensity, flashing rate) and the second switch for selectively chooses an operating mode (e.g., overt/visible, covert/infrared). At least one light emitting diode and at least one photo detector is/are electrically interfaced to the controller. An operating status configuration switch is also electrically interfaced to the controller. The operating status configuration switch is for determining the status of the marker system (by the user/wearer). A vibration device is electrically interfaced to the controller. Software is stored on a non-transitory storage associated with the controller. The software determines a mode based upon signals from the first switch and the second switch and, based upon the mode, the circuit selectively provides electrical current to one or more of the at least one light emitting diode such that the one or more of the at least one light emitting diode emit light. Upon the software detecting an incoming IFF interrogation/targeting signal from any of the at least one photo detectors, the controller provides electrical current to a subset of the at least one light emitting diode in response to the incoming IFF interrogation/targeting signal, thereby the subset of the at least one light emitting diode emits light responsive to the software detecting the incoming IFF interrogation/targeting signal. 
     The current invention has several separate and distinct user-specified functions which are combinations of (a) emission in one or more wavelengths, (b) intensity variation—from off to very low brightness to strobe-level brightness, and (c) operation at differing flash rates, steady, or coded. The marking system combines the function and utility of multiple single-purpose functions into a single, marker device that is, for example, programmable to provide four user-defined identification/marker functions within two operating modes with optional user-defined IFF interrogation/targeting response functions. The marker system has multi-directional signal emission and acquisition operating profile. Such visual and infrared identification/marking capabilities combined with IFF interrogation/targeting signal response functions are intended to both save lives in close combat as well as provide an important anti-fratricide feature for long-range sniper operations at night. 
     The marker system combines visible and/or covert personnel identification and marking functions and IFF interrogation/targeting signal response features into a single device for mounting to or integrating upon, for example, a military helmet. 
     In some embodiments, the marker system provides a photo sensor array comprising at least one photo sensor. The photo sensor(s) are coupled to a processing system to acquire and process incoming infrared laser signals from any line-of-sight direction. Upon detection of an interrogation or targeting signal, the marker system emits a response to the source of that incoming signal (the interrogator) that indicates to the interrogator that the person wearing the marker system is a “friendly” person/combatant. The response is a clear, unambiguous signal to the interrogator not to engage (fire on) the person/combatant. 
     Being that the types of photo sensors required are typically expensive (e.g. InGaAs photo diodes), it is desired to reduce the number of photo sensors, while providing the ability to detect incoming infrared laser signals in all directions (e.g. full 360 degree range). Therefore, in some embodiments, a single photo sensor is in optical continuity with a lens or reflector. The lens or reflector captures the incoming infrared laser signals coming from multiple directions and directs light from the incoming infrared laser signals upon the single photo sensor. 
     In some embodiments, the marker system provides an alert to the user/wearer, with tactile, visual and/or aural signals, after the marker system receives an incoming IFF interrogation/targeting signal (e.g., a preprogrammed or expected interrogation). In some embodiments, such feedback is provided by a device or emitter (e.g., vibratory motor, visible emitter, light-guide termination, sound generator) that is connected to the marker system via an electrical, fiber-optic, or other type of cable. 
     In some embodiments, the marker system provides operating status confirmation (OSC) feedback for the user/wearer to confirm, on demand, whether the device is in an INACTIVE state (wherein the device is not emitting in any spectrum and/or is not receptive or responsive to an IFF interrogation), in an ON state (wherein the device is emitting an identification/marker and/or is receptive and responsive to an IFF interrogation) and/or in a STANDBY state (wherein the device is not emitting any identification/marker spectrum, but is receptive and responsive to an IFF interrogation). 
     In some embodiments, the marker system provides the operating status confirmation (OSC) feedback by activation via a switching that is disposed upon the marker system, and that the feedback is provided through the operating status confirmation (OSC) feedback (e.g., vibratory motor, visible emitter, light-guide termination, sound generator), such feedback may be integral to the device itself and/or provided remote from the device, wired or wirelessly connected to feedback means inside the helmet or visible on the front inner edge of the helmet or in a heads-up display mounted to the helmet. 
     In some embodiments, the marker system is provided in a housing comprising controls there on and in some embodiments the housing has a minimally obstructive shape on all sides and edges for mounting on helmets, other equipment, or structures, reducing snag potential or interference with objects that may be encountered during ground combat operations or parachuting, including interference with parachute lines and risers. 
     In some embodiments, the marker system is provided with a non-planar base, the bottom surface of the base has an arcuate concavity to fit the contour of the external shell of a military helmet, for example using an interfacing material such a hook and loop material or self-adhesives. 
     In some embodiments, the marker system provides a selector to select between two distinct and independent operating modes (e.g., visible/overt and infrared/covert) with one or more discreet visible and/or infrared emission function profiles in each operating mode. In some such embodiments, these independent function sets are separated and segregated by one or more separate switches disposed upon the housing and/or the base. 
     In some embodiments, the marker system provides a plurality of emitters to allow a user-defined selection of different operating functions in the visible and/or infrared spectrum. 
     In some embodiments, the marker system provides the variety and combination of user-defined functions described on a standard, common hardware platform that is changeable through software/firmware programming. 
     In some embodiments, the marker system provides a housing through which emitted light radiates in an omni-directional fashion providing line-of-sight visual access over a full hemisphere relative to the device ground plane when mounted/installed. 
     In some embodiments, the marker system is configured to facilitate secure, conformal mounting to standard attachment devices built onto the helmet structure (e.g., Picatinny rails), or other worn equipment (e.g., tactical vests, web gear, armor plate carriers). 
     In some embodiments, the marker system includes at least one emitter that emits light responsive to a flow of electrical current through the emitter(s). There is a set of devices for acquiring incoming signals that also provide directional data (e.g., an indication of the direction of the incoming signal). There is a processing element for processing the incoming signals. The processing element monitors the devices for acquiring the incoming signals and determines if the incoming signals includes any of a plurality of incoming Identification Friend or Foe (IFF) and munitions-targeting signals. There is also a device for notifying a user of the marker system (e.g. illumination or vibration). Upon detecting an incoming Identification Friend or Foe (IFF), the processing element notifies the user by way of the device for notifying; the notification includes a direction from which the Identification Friend or Foe (IFF) came. Upon detecting an incoming munitions-targeting signal, the processing element notifies the user by way of the device for notifying; the notification includes a direction from which the munitions-targeting signals came. 
     In some embodiments, a marker system includes a controller having a plurality of emitters electrically interfaced thereto such that, upon the controller initiating a flow of electric current though one or more of the emitters, the one or more of the emitters emit light. There is a device for notifying a user of the marker system and at least two detectors electrically interfaced to the controller. The at least two detectors detect light in of a specific wavelength and convert the light into an electrical signal that is received by the controller. The at least two detectors RE oriented within the marker system to provide a directional indication of the detecting the light. Software associated with the controller monitors the detectors and upon detecting an incoming Identification Friend or Foe (IFF), the software notifies the user using the device for notifying. Upon detecting an incoming munitions-targeting signal by the software, the software notifies the user using the device for notifying. 
     In some embodiments, the marker system includes a controller, a switch electrically interfaced to the controller, a plurality of light emitting diodes, at least one photo detector that is/are electrically interfaced to the controller, and a vibration device electrically interfaced to the controller. Each of the light emitting diodes emits light when provided electrical current under control of the controller. The at least one photo detector is/are positioned within the marker system to provide directional data. Software stored associated with the controller invokes the controller to provide electrical current to one or more of the light emitting diodes such that the one or more of the light emitting diodes emit light, either steady or blinking based upon the position of the switch. Upon the software detecting an incoming Identification Friend or Foe (IFF) signal received by any of the at least one photo detector, if the switch is set to a non-stealth mode, the software provides electrical current in a first pattern to a first subset of the light emitting diodes to respond to the incoming Identification Friend or Foe (IFF). Upon the software detecting an incoming munitions-targeting signal received by any of the at least one photo detector, if the switch is in a non-stealth mode, the software provides electrical current in a second pattern to a second subset of the light emitting diodes to respond to the incoming munitions-targeting signal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
         FIG. 1  illustrates a rear oblique view of the marker system. 
         FIG. 2  illustrates a front oblique view of the marker system. 
         FIG. 3  illustrates a bottom oblique view of the marker system with the user feedback device shown disconnected. 
         FIG. 4  illustrates an exploded view of the marker system. 
         FIG. 5  illustrates a view of the marker system attached to the top of a helmet, showing one potential position of feedback device positioned inside the helmet. 
         FIG. 6  illustrates a view of the marker system mounted to a fabric cover of a helmet by an intermediate attachment system that is affixed to the fabric cover. 
         FIG. 7  illustrates a view of the marker system attached to the top of a helmet by way of a helmet-integrated attachment and interconnection system and connected to a helmet-integrated battery source and helmet-integrated feedback device. 
         FIG. 8  illustrates a schematic view of a first exemplary marker system circuit. 
         FIG. 8A  illustrates a schematic view of a second exemplary marker system circuit. 
         FIG. 9  illustrates a schematic view of an exemplary marker system controller circuit. 
         FIG. 10  illustrates a schematic view of an exemplary connection and programming capability for the marker system. 
         FIG. 11  illustrates a first flow chart of exemplary software for executing on the controller system of the marker system. 
         FIG. 12  illustrates a second flow chart of exemplary software for executing on the controller system of the marker system. 
         FIG. 13  illustrates a third flow chart of exemplary software for executing on the controller system of the marker system. 
         FIG. 14  illustrates a fourth flow chart of exemplary software for executing on the controller system of the marker system. 
         FIG. 15  illustrates a view of an exemplary cellphone communicating with the marker system. 
         FIG. 16  illustrates a schematic view of an exemplary cellphone. 
         FIG. 17  illustrates a combatant entering a warning zone. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. 
     Referring to  FIGS. 1-4 , views of the marker system  10  are shown. The marker system  10  includes a housing  12  that encloses and protects electronic components there within. Although many different housings  12  are anticipated, the housing  12  shown as an example includes a snag-resistant, generally convex upper area  14  that, at least part of the upper area  14  permits the passage of light out of and into the housing  12 . In some embodiments, the housing  12  is convex and inwardly sloping to reduce snag hazards, as one of the intended uses of the marker system  10  is for parachuting and there is a need to prevent parachute lines and risers from snagging on the marker system  10 . In this embodiment, the upper area  14  of the housing  14  connects to a base  28  (or lower portion  28 ) of the housing at a sealing surface  16 . Also, in a preferred embodiment, the lower surface  32  of the base  28  is generally concave so as to conform to the contour of military headgear such as a military or parachuting helmet, though in some embodiments, the lower surface  32  is generally planar to conform and mount on other surfaces. In some embodiments, the lower surface  32  of the housing  12  removably attaches to a surface with a material such as hook and loop material. 
     In some embodiments, the base  28  includes an opening  136  that extends through the lower portion  28  and exits the lower surface  32  at a hole  132 . This opening  132 / 136  allows for attaching a security cord to the marker system  10  to prevent loss should the material holding the marker system  10  fail (e.g., the hook and loop material is disengaged by coming in contact with another object or structure). 
     In embodiments in which the housing  12  separates from the base  28 , there is a way to reduce the potential of water and/or moisture intrusion such as a seal  38  between the housing  12  and base  28 , and there is a mechanism to attach the housing  12  and base  28  in order to maintain this sealing, such as a set of screws  26  passing through holes or bosses  22  in the base and setting in bosses in the upper part  14  of the housing  12 , or alternate attachment means such as ultrasonic welding. 
     Switches  60 / 66 / 120  are disposed upon the housing  12  and/or the base  12 . A mode switch  66  provides for the selection of one or more operating modes (e.g., visible/overt and infrared/covert). A function switch  60  provides for the selection of two or more operating functions (e.g., various emission spectra, intensity, flashing or steady operation) within each of the one or more operating modes (e.g., visible/overt, infrared/covert). When the operating status confirmation (OSC) switch  120  is activated, the operating status confirmation (OSC) switch  120  provides the user/wearer confirmation that the device is either INACTIVE, ON or in a STANDBY state. In the embodiment shown, the mode switch  66  is disposed upon the front of the housing, the function switch  60  is mounted on the back of the housing, and the operating status confirmation (OSC) switch  120  is integrated into the function switch retainer  64 . There is no limitation on arrangement, placement, mounting, or style of the switches  60 / 66 / 120 . Additionally, in some embodiments, the number and type of switches varies as for some applications, there are more or less switches with the same or different functionality. 
     Although there are many know switching arrangements, the example shown provides for a switching arrangement that reduces the possibility of water intrusion using magnets and reed switches communicating through waterproof barriers without the need for electrical wire interfaces passing through watertight enclosures. The function switch  60  includes a magnet  62  and a function switch retainer  64  held by a screw  26 . As the function switch  60  is moved between positions as defined by split capture rings  84  within the function switch retainer  64 , the magnet  62  moves into proximity with a corresponding reed switch (not shown) on a circuit board  54 . The reed switches interface to a control circuit  200  (see  FIGS. 8, 8A, and 9 ). The magnetic field passes from outside the housing, through the material of the housing and closes the reed switch on the interior of the housing that the magnet  62  is in proximity of, without compromising the waterproofness of the housing with wires passing from inside to outside the housing. Likewise, the mode switch  66  includes a magnet  68  imbedded within the mode switch  66  and held in place by, for example, a mode switch retainer  70  that is held to the housing  12  by screws  26 . The mode switch retainer  70  retains the mode switch  66  allowing it to slide or otherwise move the embedded magnet  68  from one position to another. Another reed switch (not shown) is in proximity to one of the cavities supported by a circuit board  52  and this reed switch is interfaces to the control circuit  200  (see  FIGS. 8, 8A, and 9 ), such that the circuit is able to determine the position of the mode switch  66  and magnet  68 . The intent of such a mode switch  66  is to enable easy tactile identification of the position of the mode switch  66  in low-light conditions. The mode switch  66  is configured and/or shielded in such as way prevent inadvertent snagging and or movement from covert (infrared) into the overt (visible) emission mode in dark of night conditions, and thus make the user/wearer visible to enemy combatants. In the embodiments shown, the operating status confirmation (OSC) switch  120  includes a micro switch  121  that is interfaces to the control circuit  200  (see  FIGS. 8, 8A, and 9 ). Again, there are no limitations as to the number, type, configuration, size, and/or location of the various switches  60 / 66 / 120 . 
     Various emitters  58   a / 58   b / 58   c  are positioned, preferably, within the enclosure  12 , shown for example connected to a circuit board  52 . The emitters  58   a / 58   b / 58   c  are, for example, light emitting diodes (LEDs)  58   a / 58   b / 58   c  emitting any or all of a variety of wavelengths and intensities under control of the control circuit  200  (see  FIGS. 8, 8A , and  9 ). By providing proper electrical flow through the emitters  58   a / 58   b / 58   c , the control circuit  200  causes the emitters to emit the desired light as determined by the programming of the control circuit  200  and the settings of the switches  60 / 66 / 120 . For example, a first set of emitters  58   a  are multi-chip light-emitting-diodes (LEDs) configured to emit red, green, and blue light individually or in combination based upon which internal chip(s) are provided with power, thereby providing a range of visible colors. Another emitter  58   b , for example, is a high-intensity white emitter (LED). Yet another emitter  58   c , for example, is/are infrared (IR) emitters, emitting light that is not generally visible to the naked eye of a human, in one or more wavelengths of infrared light. As will be shown, the controller  200  energizes one, multiple, or all emitters  58   a / 58   b / 58   c  as determined by setting of the switches  60 / 66 / 120  and stored programming to eliminate at a desired brightness, wavelength, and continuously or blinking/flashing. 
     In embodiments in which the marker system supports “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition and response capabilities, one or more detectors  92  are provided, electrically interfaced to the control circuit  200  (see  FIGS. 8, 8A, and 9 ), for example, by the circuit board  52 . The detectors  92 , typically photo diodes, receive light from outside the housing  12 . As will be explained, the detectors  92  receive light of a particular wavelength that is typically encoded with a secure code representing an IFF interrogation or munitions targeting signal. 
     In some embodiments, the detectors  92  respond to a certain spectrum of light such as the full infrared spectrum. In such, the marker system  10  detects any pre-determined IFF interrogation or munitions targeting signal on any light frequency of which the detectors  92  operate. In some embodiments, the detectors  92  provide both an signal level for detection of the pattern received (e.g. the IFF interrogation or munitions targeting signal encoding), as well as an indication of the spectrum of light on which the IFF interrogation or munitions targeting signal is received. For example, the detectors  92  provide an indication of either near infrared, short-wavelength infrared, mid-wavelength infrared or long-wavelength infrared, etc. By having such information, the marker system  10  is programmable to respond to one or more specific spectrums and one or more specific encodings of IFF interrogation or munitions targeting signal on each spectrum and/or provides notification of which wave-length is received. For example, the marker system  10  is programmed to only respond to an IFF interrogation on near infrared and to a munitions targeting signal on short-wavelength infrared. In such, security is improved as the enemy will not know which wavelength is carrying which type of signal, etc. In some such embodiments, the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received over multiple wavelengths. For example, parts of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition are received on two separate wavelengths, either simultaneously or alternating between the wavelengths. 
     In some embodiments, the detectors  92  are positioned directionally to determine a direction of the source of the transmission of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition. As for example, the arrangement of the detectors  92  in  FIG. 4  provides for determination of direction in four general quadrants as the detectors  92  are aimed at 45 degrees, 135 degrees, 235 degrees, and 315 degrees (assuming 0 degrees is directly in front of the marker system  10 ). In such, if one detector  92  receives a stronger signal than the other detectors  92 , it is determined that the signal emanates from the respective direction. Additionally, a detector  92  aimed upwards as shown in  FIG. 4  also provides for determining when the source of the transmission of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is above the marker system  10  (e.g. aerial or from a building, etc.). Although shown as five detectors  92  mounted at 45 degrees, 135 degrees, 225 degrees, 315 degrees, and above, any number of detectors  92  mounted in any configuration is anticipated. For example, two detectors  92  mounted at 90 degrees and 270 degrees for determining if the source of the transmission of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is to the right or to the left of the marker system  10 . 
     In the case of IFF interrogation (e.g., light of a particular wavelength that is typically encoded with a secure code), the light is transmitted from a remote device aimed by a first combatant at a second combatant wearing the marker system  10 . The first combatant is trained to expect a known response from friendly combatants such as a predetermined flashing of one or more of the emitters  58   a / 58   b / 58   c , for example, a predetermined number of flashes of an infrared emitter  58   c , on for a predetermined period and off for a predetermined period. In this way, a first combatant (e.g., a sniper) uses a device to transmit the interrogation to the maker system  10  worn by a second combatant and the marker system, recognizing the secure code, properly responds to the interrogation, communicating to the first combatant (e.g., sniper) that the second combatant is friendly. Otherwise, the first combatant (e.g., sniper), in absence of the proper response, will assume the second combatant is not friendly (e.g., a foe) and take appropriate action and/or engagement. 
     In the case of a munitions targeting signal (e.g., light of a particular wavelength that is typically encoded with a secure code) is transmitted by a first combatant operating either a handheld, aircraft-installed, or vehicle-installed munitions targeting device, and such signal impinges upon the marker system  10  worn by the second combatant. In this case, the first combatant was not likely aware that the second combatant was in the first combatant&#39;s target zone. Upon acquisition and processing of the incoming targeting signal by the marker system  10  worn by the second combatant, the marker system  10  emits, for example, a predetermined flashing of one or more of the emitters  58   a / 58   b / 58   c , for example, a predetermined number of flashes of an infrared emitter  58   c , on for a predetermined period and off for a predetermined period, thus alerting the first combatant that the second, friendly combatant in the target zone and can abort launch of the targeting signal-guided munitions. Otherwise, the first combatant operating the munitions targeting device in absence of a response, assumes the target area is free of friendly combatants and proceeds with the launch of targeting signal-guided munitions. 
     In some embodiments, there is a mechanism for notifying the user of the marker system  10  that an IFF interrogation or munitions targeting signal was received and recognized. In the embodiments of  FIGS. 1-4 , an external vibratory pad  104  is provided, connected to the marker system  10  by a cable  102  (e.g. one or more grouped wires or fiber optics). In the example of  FIGS. 1 and 2 , one end of the cable  102  is connected to a vibration device  110  within the vibratory pad  104  and the other end of the cable  102  passes into the housing  12  and is connected to the control circuit  200  (see  FIGS. 8, 8A, and 9 ). In the example of  FIGS. 3 and 4 , one end of the cable  102  is connected to a vibration device  110  within the vibratory pad  104  and the other end of the cable terminates in a connector  112  that plugs into a mating connector  33  of the housing  12 , electrically interfacing to the control circuit  200  (see  FIGS. 8, 8A, and 9 ) through, for example, contacts  113  of the connector  112  making electrical contact with mating contacts  115  of the mating connector  33 . Note that in some embodiments, the connector  112  has a seal  114  to prevent moisture from penetrating and getting into the area of the contacts  113 / 115  when connected. Although any vibration device  110  is anticipated, in some embodiments, the vibration device  110  comprises a motor having an offset mass on the shaft of the motor such that, when the motor is energized by the control circuit  200 , the offset mass creates vibration. 
     In some embodiments, an internal vibration generating device  108  is present within the enclosure defined by the housing  14  and the base  28 , under control of the controller  200 . 
     In some embodiments, the mechanism for notifying the user of the marker system  10  is a helmet-mounted heads-up display  59  that provides visual indication of reception of an IFF interrogation or munitions targeting signal was received and recognized. 
     In some embodiments, the mechanism for notifying (e.g. helmet vibratory pad  104 ) is mutable or pausable by the operator. 
     In embodiments with directionally capability (e.g. having directionally orientated detectors  92 ), the notification includes an indication of direction of the source of the transmission of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition. In some embodiments, the vibration pattern is varied based upon the direction from which the source of the transmission of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is coming from. For example, a long vibration followed by a number of short vibrations indicating direction (one short vibration for 45 degrees, two short vibrations for 135 degrees, three short vibrations for 225 degrees and four short vibrations for 315 degrees). In this example, an additional long vibration indicates the source of the transmission of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is above the marker system  10 . 
     In some embodiments, a helmet-mounted heads-up display provides visual indication of reception the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition. In such embodiments, upon reception of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition, an emitter  59  (see  FIG. 8A ) provides visual indication of reception the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition. In embodiments with directional detection, the emitter  59  has multiple LEDs for the indication of direction. For example, two LEDs having masking in the form of left and right arrows provide indication of the source being to the left or the right, respectively. As another example, the emitter is a single LED having multiple color outputs (e.g. an Red/Blue/Green LED for additive color production) and the color from the emitter is used to convey the direction of the source of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition. For example, red for 45 degrees, yellow for 135 degrees, green for 225 degrees and violet for 315 degrees and blinking for reception from above. 
     In some embodiments in which detectors  92  have features to determine and provide indication of the wavelength on which the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received; the notification indicates which wavelength was received. In some such embodiments, the vibration pattern is varied based upon the wavelength of the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is coming from. For example, a long vibration followed by a number of short vibrations indicating the wave-length (one short vibration for near infrared, two short vibrations for short-wavelength infrared, three vibrations for mid-wavelength infrared, or four vibrations for long-wavelength infrared). 
     In some embodiments, the response to “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is made with emitters emitting the same wavelength of light than the received wavelength of light. For example, if the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received in the near-infrared wavelengths, then the emitters signal the response over the near-infrared wavelength. In other embodiments, the response to “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is made with emitters emitting a different wavelength of light than the received wavelength of light. For example, if the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received in the near-infrared wavelengths, the emitters signal the response over the long-infrared wavelength. 
     Various other exemplary components are shown for completeness including a helmet interface substrate  36  (e.g. mating hook or loop material, or self-adhesive material), battery contacts  42 , battery  44 , battery enclosure and retention components  30 / 40 / 46 / 48 / 49 / 88 , and circuit components  90  (e.g., resistors, capacitors, transistors, etc.), etc. 
     Referring to  FIG. 5 , a view of the marker system  10  attached to the top of a helmet  140 , showing one potential position of vibratory pad  104  positioned inside the helmet  140  is shown. In this example, the marker system  10  is attached to the top of the helmet  140  by, for example, hook and/or loop material  130  interfacing with the helmet interface substrate  36  and the cable  102  is draped over a surface of the helmet  140  and around a rim of the helmet  140 , positioning the vibratory pad  104  inside the helmet  140 , for example, against the wearer&#39;s head such that the wearer will feel the vibration when an interrogation is received. 
     Referring to  FIG. 6 , the marker system  10  is shown mounted to a fabric cover  148  of a helmet  140  by an intermediate attachment system  150  that is affixed to the fabric cover  148 . In this example, the marker system  10  is attached to the top of the helmet  140  by, for example, an intermediate attachment system  150  and the cable  102  is routed between the cloth cover  140  that covers the helmet  140  and a surface of the helmet  140  and then routed around a rim of the helmet  140 , positioning the vibratory pad  104  inside the helmet  140 , for example, against the wearer&#39;s head such that the wearer will feel the vibration when an interrogation is received. 
     Referring to  FIG. 7 , the marker system  10  is shown attached to the top of a helmet  140  by way of a helmet-integrated attachment and interconnection system  142 / 144  and connected to a helmet-integrated battery source  138 . In this example, the vibratory pad  104  is integrated within the helmet  140  and the marker system  10  connects to the vibratory pad  104  by cable/conductors  146  that are integrated into the helmet  140 . In this example, the marker system  10  is attached to the top of the helmet  140  by, for example, a helmet-integrated attachment and interconnection system  142 / 144 . The cable  146  and vibratory pad  104  are integrated into the helmet  140 . In such, the cable  146  is routed through an orifice within the helmet  140  and the vibratory pad  104  is provided, mounted inside the helmet  140 , for example, against the wearer&#39;s head such that the wearer will feel the vibration when an interrogation is received. Power or auxiliary power for the marker system  10  is provided by a helmet mounted power source  138  (e.g. helmet mounted battery). 
     Referring to  FIGS. 8 and 8A , schematic views of an exemplary control circuit  200  of the marker system  10  are shown. In both  FIGS. 8 and 8A , the control circuit  200  is, for example, a microcontroller or any known processing element. Any number of switches  54 / 56  are connected to inputs of the controller  200 . The switches  54 / 56  are shown as reed switches in this example, but there is no limitation as to the type of switches  54 / 56 . One or more detectors  92  are connected to inputs of the controller  200 . As light of a wavelength detected by each of the detectors  92  is received, the conductivity and/or impedance of the detector(s)  92  changes and this change is detected at the inputs to the controller  200 . Any number of emitters  58   a / 58   b / 58   c  are connected to outputs of the controller  200  such that, upon program control, the controller  200  causes current to flow through one or more of the emitters  58   a / 58   b / 58   c , causing that/those emitters  58   a / 58   b / 58   c  to emit light at a corresponding wavelength and brightness. Power is provided by a power source  44  (e.g. a battery, super capacitor, etc.). In embodiments having “Identification Friend or Foe” (IFF) interrogation and/or munitions targeting signal acquisition and response capabilities with tactile notification, the vibration generating device  110  (e.g. motor) is connected to an output of the controller  200 . 
     In  FIG. 8A , additional optional features are added, including an audio transducer  98  (e.g., a speaker, earphone, or any emitter within the audible range of hearing) and an audio detector  96  (e.g., a microphone). In some embodiments, the audio detector  96  is used to receive voice commands that are recognized and acted upon by the controller  200 . Likewise, in some embodiments, audio feedback is provided by the controller  200  through the audio transducer  96 . 
     In some embodiments, a radio  194  with associated antenna  195  is coupled to and controlled by the controller  200 . In such embodiments, the radio  194  is, for example, a transceiver for field use and/or for programming. For example, in one embodiment, the radios are Wi-Fi transceivers. Just prior to a parachuting operation, all marker systems  10  are programmed to respond to a specific interrogation code by transmitting program updates from a programming system having a complimentary Wi-Fi transceiver. The program updates are then received by all marker systems  10  by way of the radios  194  (Wi-Fi) within each marker system  10  and internal programming of the controller  200  is updated with the interrogation code. Scenarios such as this provides for enhanced security as it is more difficult for enemy forces to find out what security code is being used and, therefore, more difficult to spoof the code. 
     Also shown in  FIG. 8A  is a personnel indicator  59  either positioned at a location that is visible to the wearer (e.g. on a rim of a helmet  140 ) or optionally coupled to a light pipe  60 , where one end of the light pipe receives light from the personnel indicator  59  and a distal end of the light pipe is positioned at a location that is visible to the wearer (e.g. on a rim of a helmet  140 ), or integrated electronically directly into a helmet-mounted visual heads-up display. 
     Referring to  FIG. 9 , a schematic view of an exemplary controller  200  as used to control the operation of various output devices of the marker system  10 . The exemplary controller  200  represents a typical processor-based system as used with the marker system  10 , though it is also known in the industry to utilize logic in place of processors and vice versa. This exemplary controller  200  is shown in its simplest form. Different architectures are known that accomplish similar results in a similar fashion and the marker system  10  is not limited in any way to any particular system architecture or implementation. In this exemplary controller  200 , a processor  270  executes or runs programs from a random access memory  275 . The programs are generally stored within a persistent memory  274  and loaded into the random access memory  275  when needed. The processor  270  is any processor, typically a processor designed for portable devices. The persistent memory  274 , random access memory  275  interfaces through, for example, a memory bus  272 . The random access memory  275  is any memory  275  suitable for connection and operation with the selected processor  270 , such as SRAM, DRAM, SDRAM, RDRAM, DDR, DDR-2, etc. The persistent memory  274  is any type, configuration, capacity of memory  274  suitable for persistently storing data, for example, flash memory, read only memory, battery-backed memory, magnetic memory, etc. In some exemplary controllers  200 , the persistent memory  274  is removable, in the form of a memory card of appropriate format such as SD (secure digital) cards, micro SD cards, compact flash, etc. 
     Also connected to the processor  270  is a system bus  282  for connecting to peripheral subsystems such as output drivers  284  and inputs  189 / 192  such as control switches  92 . The output drivers  284  receive commands/signals from the processor  270  and control the emitters  58   a / 58   b / 58   c , the vibration device  104  (when present), and the audio transducer  98  (when present). The input ports  189 / 192  receive signals from the sensors  92  (when present), the audio detectors  96  (when present), and the switches  54 / 56 , and convey the signals to the processor  270  for action. Although any number of sensors  92  are anticipated, including zero, in some embodiments, there are present at least two different sensors operating at two different wavelengths. For example, a first of the sensors  92  receives interrogations at near infrared and a second of the sensors  92  receives interrogations at short-wave infrared. In another example, a first of the sensors  92  receives interrogations at short-wave infrared and a second of the sensors  92  receives interrogations at mid-wave infrared. In this way, different interrogations are received (and detected) from different sources, concurrently; for example, on one wavelength from ground troops and on another wavelength from aircraft. 
     In some embodiments, a radio  194  is provided for communications with other systems. Such communication features provide data communications between the marker system  10  and, for example, a programming system (not shown) or an operations base station (not shown) to program the controller  200  and/or activate features of the marker system  10 . 
     The peripherals and sensors shown are examples and other devices are known in the industry such as Global Positioning Subsystems  196 , USB interfaces, Bluetooth transceivers, image sensors, body function sensors, temperature sensors, etc., the likes of which are not shown for brevity and clarity reasons. 
     Referring to  FIG. 10 , a schematic view of an exemplary connection and programming capability for the marker system  10  is shown. In this example, the marker system  10  receives wireless communications in the form of electromagnetic radiation such as visible light, light that is not visible to the naked human eye, radio waves, etc. from either a programming system  508  and/or a handheld or weapon-mounted transmitter  520  and/or from an aircraft- or vehicle-mounted transmitter (not shown for clarity reasons). In embodiments having a radio  194 , one form of the electromagnetic radiation is radio waves. In embodiments absent of a radio  194 , the electromagnetic radiation is light waves and the light waves are received by the detector(s)  92 . In such, the light waves are either light waves that are visible to the naked eye of a human or light waves that are not visible to the naked eye of a human such as infrared light waves. It is anticipated that, in some embodiments, the electromagnetic radiation is modulated and/or encoded with either a programming signal or an incoming IFF interrogation signal. The process for receiving and interpreting the programming signal or/or the incoming IFF interrogation signal is described with  FIGS. 11, 12, 13, and 14 . Although any number of sensors  92  are anticipated, including zero, in some embodiments, there are present at least two different sensors operating at two different wavelengths of light. For example, a first of the sensors  92  receives interrogations at near infrared wavelengths (NIR) and a second of the sensors  92  receives interrogations at short-wave infrared wavelength (SWIR). In another example, a first of the sensors  92  receives interrogations at long-wave infrared (LIR) wavelengths and a second of the sensors  92  receives interrogations at short-wave infrared (SWIR). In this way, different interrogations are received (and detected) from different sources, concurrently; for example, on one wavelength from ground troops and on another wavelength from aircraft. 
     In general, programming is initiated by a specific operation of one of the switches  54 / 56 / 120 . For example, programming is initiated by pressing and holding the operating status confirmation (OSC) switch  120  for a number of seconds, for example five seconds or by coded manipulation/operation of one or more switches  54 / 56 / 120 . In this way, physical access to the marker system  10  is required to initiate programming, though in some embodiments, it is anticipated that programming is initiated by the programming signal without need to operate any of the switches  54 / 56 / 120 , though in such it is anticipated that the programming signal is encoded to prevent unauthorized tampering with the program of the marker system  10 . The programming signal includes, for example, updated operating software and/or parameter settings. Parameter settings are, for example, the frequency of flashing, the brightness in each mode, flags to enable/disable certain features, etc. 
     The incoming IFF interrogation signal is transmitted, typically from a handheld or weapon-mounted transmission device  520  or aircraft- or vehicle-mounted transmitters such as a transmitter emitting an infrared laser designed for any number of combat applications including illumination, marking/pointing, IFF interrogation, and munitions-targeting. Note that any form of electromagnetic radiation transmission is anticipated. Infrared laser transmission is used as an example as such transmission is not generally visible to the naked human eye and is typically very directional. When transmitted from a handheld or weapon-mounted transmission device  520 , directionality is often desired so as to only signal the user/wearer of the marker system  10  that is targeted. The incoming IFF interrogation signal is received by either the radio  194  or the detectors  92  and processed by the controller  200  to determine validity. It is fully anticipated that the incoming IFF interrogation signal be one or more specific modulations of the electromagnetic radiation having there within embedded a security code such as a cryptographic key. Encoding prevents an enemy having a transmission device  520  from sending an interrogation signal to a friendly combatant for purposes of identifying his/her position for engagement. The controller  200  decodes and processes the signal from the detector(s)  92  and/or the radio  194  to verify the proper modulation and/or encoding of the incoming IFF interrogation signal. When the controller  200  determines a valid incoming IFF interrogation signal, based upon capabilities and settings, the controller responds by illuminating one or more of the emitters  58   a / 58   b / 58   c , illuminating the personnel indicator  59  (see  FIG. 8A ), emitting a sound, and/or initiating vibration of the vibratory device  104 . Note that, as described above, the programming signal has capabilities to change settings within the marker system  10  and some of those settings are, optionally, how the marker system  10  responds to the incoming IFF interrogation signal (e.g. blinking the infrared emitters  58   c  three times or blinking the white emitters  58   a  twice, etc.) and how the marker system  10  indicates reception of an incoming IFF interrogation signal (e.g. pulsing the vibratory device  104 , etc.). 
     In some embodiments, the marker system  10  is configured to receive and detect two or more different signals at different wavelengths or codes, for example, one from handheld or weapon-mounted general purpose infrared illuminators or one from handheld, aircraft- or vehicle-mounted lasers intended for munitions targeting. For example, an aircraft emits a signal at mid-wave infrared that is received by a first of the sensors  92  and is then detected as munitions-targeting signal; and a weapon-mounted transmission device  520  emits a signal at short-wave infrared that is received by a second of the sensors  92  and is then detected as an IFF interrogation signal. Note that it is also anticipated that a single sensor  92  is capable of receiving a range of wavelengths. In some such embodiments, one or multiple different interrogations are received by radiofrequency (e.g. using the radio  194 ). 
     In some embodiments, a single response is made to either of the first type of interrogation and the second type of interrogation. In some embodiments, a first type of response is made to the first type of interrogation and a second type of response is made to the second type of interrogation. As a very general example, a first response is blinking the infrared emitters  58   c  three times and a second response is blinking the white emitters  58   a  twice, though this is in no way a limitation of the types of responses that are anticipated. 
     In some embodiments, a single indication of either of the first type of interrogation or the second type of interrogation is made such as emitting a sound, and/or initiating vibration of the vibratory device  104 . In some embodiments, a first type of indication is made to the first type of interrogation and a second type of indication is made to the second type of interrogation. As a general example, a first type of indication is three short vibrations of the vibratory device  104  (indicating being tagged by a friendly) while a second type of indication is a long and constant vibration of the vibratory device  104  (indicating being in a zone targeted by an aircraft). 
     In some embodiments, one or multiple types of responses are made by emitting radio frequency energy by the radio  194 . In such, it is known that radio frequency transmitters have limited range, especially one such as a portable radio  194  that has a small, portable antenna and is battery powered. Therefore, the response made using the radio  194  will only be received by other friendly (and foe) forces within a given radius as determined by the power output of the radio  194  and environmental parameters such as foliage, humidity, altitude, etc. 
     In some embodiments, one or multiple types of responses are made by emitting radio frequency energy by the radio  194 , which communicates with another device carried by the wearer of the marker system  10 . For example, the radio  194  is a Bluetooth transceiver and, upon detection of one or more types of interrogation, the marker system  10  transmits a Bluetooth packet that is received by the device carried by the wearer of the marker system  10  and the device carried by the wearer of the marker system  10 , responsive to receiving the packet, transmits a response using, for example, a higher power radio transmission. 
     It is fully anticipated that any or all of the input spectra, output spectra, frequency, modulation, duty cycle, date-coding, intensity, mode of output, vibration amplitude, vibration frequency, vibration mode, etc., is programmable through any programming mechanism described, including, but not limited to, programming through light waves received by the sensor(s)  92 , programming through the radio  194 , programming though operation of one or more switches  54 / 56 , programing through voice recognition using, for example, a microphone  96 , etc. For example, in one embodiment, the marker system  10  is configured with two distinct modes of operation. In a first mode, the marker system responds to a first type of indication with a first type of response and responds to a second type of indication with a second type of response. In a second mode, the marker system responds to a third type of indication with a third type of response and responds to a fourth type of indication with a fourth type of response. To change between modes, one operates the switches  54 / 56  in a specific sequence, for example, holding switch  54  for five seconds to toggle between modes. In some embodiments, light is emitted by one or more of the emitters  58   a / 58   b / 58   c  indicating the resulting mode. In another example, a programming device  508  (see  FIG. 10 ) is used to change modes, etc. 
     In some embodiments, the modulation scheme and/or encoding is programmable through the programming signal. In this, one or more secure protocols are accessible to the programming system  508  and, for example when a field operation begins; a selected one of the secure protocols (e.g. modulation scheme and/or encoding) is programmed into each of the marker systems  10  and also into each of the field transmission devices  520 , thereby synchronizing the protocols and encoding between all systems to enable communications for the field operation. It is also anticipated that there is an expiration time (or timer) associated with the modulation scheme and/or encoding such that, after the expiration, the modulation scheme is disabled or erased to prevent usage by enemy personnel. As an example, the secure modulation scheme and/or encodings are stored in a storage area  506  that is either accessible to the programmer  508  and/or transmitted to the programmer  508  through a security server  504  and through a network  502 , such as a wireless or wired network. 
     In some embodiments, the marker system  10  includes a global positioning radio receiver  196  for receiving signals from a global positioning satellite  500 . When present, the global positioning radio receiver  196  provides location coordinates to the controller  200 . On anticipated use of such is to restrict the location of use of the marker system  10  to a specific geographic area and/or modify the operation of the marker system when moving from one geographic area to another geographic area. For example, in high-attitude/high-opening (HIHO) or high-altitude/low-opening (HILO) parachuting operations, the marker system  10  may be configured to emit visible green light for the parachutists for setting up a flying formation during the initial stay of flight while well away from the drop zone and visual security is not required, then when the parachutists are in proximity to the drop zone and visual security is required, the marker system  10  detects the location change from the global positioning radio receiver  196  and reconfigures change from visible green to infrared light, etc. 
     Referring to  FIGS. 11, 12, 13 and 14 , flow charts of exemplary software for executing on the controller system  200  of the marker system  10  are shown. As described previously, the controller system reads settings of one or more switches  54 / 56 / 120  and, from the settings, the software a function and a mode. The mode switch  66  provides for the selection of one or more operating modes (e.g., mode-A is visible/overt and mode-B is infrared/covert). The function switch  60  provides for the selection of operating functions within each mode of operation (e.g., function- 0  is OFF/standby, function- 1  is one operating function, and function- 2  is a second operating function). The operating status confirmation (OSC) switch  120  is a momentary contact switch that is pressed for a period of time to provide status of the marker system  10 , or to initial the field re-programming mode. In combination with the remote and on-board vibratory devices, in some embodiments, pressing the OSC switch further defines the state of the marker system  10  (e.g., pressing the OSC switch only causes the vibratory device  104  located inside the helmet to vibrate signals that the marker system  10  is in the OFF/STAND-BY mode and not emitting, whereas vibration of the on-board vibratory device  108  indicates that both the IFF interrogation/targeting signal features of the market system  10  are ON, and that the device is currently emitting its marker signal.) Again, this is one configuration of switches used as an example, as any number, type, and configuration of switches is anticipated. 
     In some embodiments, the user selectable operating modes include three selectable modes. A first of such modes is a passive identification mode. In such, the marker system  10  periodically emits a signal (e.g., infrared on one or more wavelengths). If the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received in any wavelength/spectrum of light, either in a single spectrum or alternating between spectrums, the marker system  10  responds with the predetermined response sequence (e.g. reducing the period of the signals that are emitted). A second mode of operation provides a partially secure mode or partial stealth mode in which the marker system  10  does not emit a signal until the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received in the pre-determined wavelength/spectrum of light, in either a single spectrum or alternating between spectrums. The marker system  10  responds with the predetermined response sequence (e.g. emitting a pattern of infrared light on a predetermined spectrum). A Third mode provides secure, total blackout operations or stealth mode in which no responses are emitted (no infrared emission). In the third mode, if the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received in the pre-determined wavelength/spectrum of light, in either a single spectrum or alternating between spectrums, notification to the wearer is made (e.g., through vibrating the external vibratory pad  104  or illuminating the heads-up display  39 ), but no response is emitted. In this way, the wearer of the marker system  10  will realize that they are being targeted and can take evasive actions. 
     In the first or second mode, it is anticipated that the marker system  10  is programmable to respond in the same wavelength of light as the wavelength that “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received. It is also anticipated that the marker system respond in a different wavelength of light than that the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received. Alternately, the “Identification Friend or Foe” (IFF) interrogation and/or targeting laser acquisition is received in multiple wavelengths and the response is made in one or multiple wavelengths/spectrums, either the same or different wavelengths. 
     In  FIG. 11 , the first step is to cut off power  600  to all sets of emitters  58   a / 58   b / 58   c . For simplicity, the first set of emitters  58   a  are referred to as L 1  (e.g. multi-color), the second set of emitters  58   b  are referred to as L 2  (e.g. bright-white), and the third set of emitters  58   c  are referred to as L 3  (e.g. infrared). For example, L 1  are a first set of visible color emitters  58   a , L 2  is a second set of visible color of emitters  58   b , and L 3  is a third set of non-visible emitters  58   b . Note that a set is any number of emitters  58   a / 58   b / 58   c  and visible/invisible is determined by the naked eye of a human. For example, white light is visible to the naked eye of a human while certain or all wavelengths of infrared light is not visible to the naked eye of a human. 
     Next, a test  602  is performed to determine if the marker system  10  is set to function- 0  (OFF/Standby). If the marker system  10  is set to function- 0 , step  600  is repeated until a change to the switches changes to a different function, at which time it is determined by another test  604  if the marker system  10  is set to function- 1 . If the marker system  10  is set to function- 1   604 , then a test  610  is made to determine the mode setting (Mode-A being overt and Mode-B being covert). If the mode is Mode-A  610 , then power is provided  614  to the first set of emitters L 1 , which then emit light, for example, at a certain visible wavelength (to the naked eye of a human). If the mode is Mode-B  610 , then power is provided  612  to the third set of emitters L 3 , which then emit lights, for example, in a certain non-visible wavelength (to the naked eye of a human). A test is made  616  to determine if the marker system  10  is still in function- 1  and if so, step  610  is repeated, otherwise, flow resumes at step  602  and the above repeats. Note that in some embodiments, the amount of power (e.g. current) provided to the emitters L 1  and/or L 3  is determined by a preset or programmed parameter and, in some embodiments, the frequency of the power (e.g., current) provided to the emitters L 1  and/or L 3  is also determined by a preset or programmed parameter to provide blinking or flashing at a desired rate. 
     If the marker system  10  is not set to function- 1   604 , a test  606  is made to determine if the marker system  10  is set to function- 2   606 . If the marker system  10  is set to function- 2   606  then a test  620  is made to determine the mode setting (Mode-A being overt and Mode-B being covert). If the mode is Mode-A  620 , then power is provided  624  to the second set of emitters L 2 , which then emit light, for example, at a certain visible wavelength (to the naked eye of a human). If the mode is Mode-B  620 , then power is provided  622  to the third set of emitters L 3 , which then emit lights, for example, in a certain non-visible wavelength (to the naked eye of a human). A test is made  626  to determine if the marker system  10  is still in function- 2  and if so, step  620  is repeated, otherwise, flow resumes at step  602  and the above repeats. Again, note that in some embodiments, the amount of power (e.g. current) provided to the emitters L 2  and/or L 3  is determined by another preset or programmed parameter and, in some embodiments, the frequency of the power (e.g., current) provided to the emitters L 1  and/or L 3  is also determined by a preset or programmed parameter to provide blinking or flashing at a desired rate. It is fully anticipated that, based upon such parameters, the brightness, color, and or blinking rate is the same or different in function- 2  than in function- 1 . 
     A slightly different configuration is shown in  FIG. 12 , including operation of the operating status confirmation switch  120 . In  FIG. 12 , again, the first step is to cut off power  700  to all sets of emitters  58   a / 58   b / 58   c.    
     Next, a TST routine is invoked to determine if the operating status confirmation switch  120  has been pressed, that after returning from that routine, a test  702  is performed to determine if the marker system  10  is set to function- 0  (OFF/Standby). If the marker system  10  is set to function- 0 , step  700  and the TST routine is repeated until a change to the switches changes to a different function, at which time it is determined by another test  704  if the marker system  10  is set to function- 1 . If the marker system  10  is set to function- 1   704 , then a test  710  is made to determine the mode setting (Mode-A being overt and Mode-B being covert). If the mode is Mode-A  710 , then power is provided  714  to the first set of emitters L 1 , which then emit light, for example, at a certain visible wavelength (to the naked eye of a human). If the mode is Mode-B  710 , then power is provided  712  to the third set of emitters L 3 , which then emit lights, for example, in a certain non-visible wavelength (to the naked eye of a human). Next, a test is made  716  to determine if the marker system  10  is still in function- 1  and if so, an IFF routine is executed then flow resumes at step  710 . Otherwise, flow resumes at step  702  and the above repeats. Note that in some embodiments, the amount of power (e.g. current) provided to the emitters L 1  and/or L 3  is determined by a preset or programmed parameter and, in some embodiments, the frequency of the power (e.g., current) provided to the emitters L 1  and/or L 3  is also determined by a preset or programmed parameter to provide blinking or flashing at a desired rate. 
     If the marker system  10  is not set to function- 1   704 , a test  706  is made to determine if the marker system  10  is set to function- 2   706 . If the marker system  10  is set to function- 2   706  then a test  730  is made to determine the mode setting (Mode-A being overt and Mode-B being covert). If the mode is Mode-A  730 , then power is provided  734  to the second set of emitters L 2 , which then emit light, for example, at a certain visible wavelength (to the naked eye of a human). If the mode is Mode-B  720 , then power is provided  732  to the third set of emitters L 3 , which then emit light, for example, in a certain non-visible wavelength (to the naked eye of a human). Next, a test is made  736  to determine if the marker system  10  is still in function- 2  and if so, the IFF routine is executed, then flow resumes with step  730 . Otherwise, flow resumes at step  702  and the above repeats. Again, note that in some embodiments, the amount of power (e.g. current) provided to the emitters L 2  and/or L 3  is determined by another preset or programmed parameter and, in some embodiments, the frequency of the power (e.g., current) provided to the emitters L 2  and/or L 3  is also determined by a preset or programmed parameter to provide blinking or flashing at a desired rate. It is fully anticipated that, based upon such parameters, the brightness, color, and or flashing rate is the same or different in function- 2  than in function- 1 . 
     The TST routine polls the position of the operating status confirmation switch  120  which, as discussed, is preferably a momentary contact switch. If the operating status confirmation switch  120  is not closed  750 , the TST routine is done and returns. If the operating status confirmation switch  120  is closed  750 , a timing loop  752  begins, looping until it is detected that the operating status confirmation switch  120  has opened. Note that for brevity, the typical switch de-bounce logic is not shown. The operation of the operating status confirmation switch  120  includes a short hold when the user desires status and a longer hold when the marker system  10  is to be programmed. Once it is detected that the operating status confirmation switch  120  has opened, if the time held is determined to be greater than a threshold (e.g., greater than five seconds), a programming subroutine is initiated (see  FIG. 14 ). Otherwise, indication is performed  756  optionally including vibrating the external vibratory pad  104 , vibrating the internal vibrator  108 , and/or illuminating one or more status indicator emitter(s)  59  (see  FIG. 8A ) that are, for example, made visible to the wearer through a fiber optic channel  60  that directs light from the emitters  59 , for example, to an edge of the user&#39;s helmet. In such, the status indicator emitter(s)  59  radiate visible light so as to be visible by the user. 
     In  FIG. 13 , in systems that support incoming IFF interrogation/targeting signals, testing and processing regarding any incoming signal is made. First, a test  800  is made to determine if an IFF interrogation/targeting signal is incoming. If no incoming IFF interrogation/targeting signal is detected, the IFF routine exits (e.g., no radio transmission is detected or no signal is detected at the detectors  92 ). If a signal is present, possibly being the start of an incoming IFF interrogation/targeting signal, the IFF routine receives the incoming IFF interrogation/targeting signal  804 . In general, there are many known ways to modulate and/or encode the IFF interrogation/targeting signals, all of which are included here within. The marker system  10  has the ability to detect and decode any number of different IFF interrogation/targeting signals and, for each different IFF interrogation/targeting signal, the maker system  10  is capable of responding either the same way for all IFF interrogation/targeting signals, or differently, depending upon configuration parameters. In the example shown in  FIG. 13 , three different incoming IFF interrogation/targeting signals are recognized, with up to three different actions based upon configuration parameters. 
     First, a test  806  is made to determine if the incoming IFF interrogation/targeting signal is a first type, and, if so, a specific response is made  820  and a specific notification is made  822 . An example of a response made  820  is a specific pattern of flashing of the indicators  58   c  that are not visible to the naked eye. An example of a notification  822  is a specific sequence of vibrations at, for example, the vibratory pad  104  and/or illumination of the status indicator  59 . The notifications  822  provide the wearer with an indication that the wearer is being illuminated by an IFF interrogation or munitions targeting signal. After the response  820  and notification  822 , the IFF routine exits. 
     If the incoming IFF interrogation/targeting signal is not the first type, a test  808  is made to determine if the incoming IFF interrogation/targeting signal is a second type, and, if so, a specific response is made  824  and a specific notification is made  826 . An example of a response made  824  is a specific pattern of flashing of the indicators  58   c  that are not visible to the naked eye. An example of a notification  826  is a specific sequence of vibrations at, for example, the vibratory pad  104  and/or illumination of the status indicator  59 . The notifications provide the wearer with an indication that the wearer is being illuminated by an IFF interrogation/targeting signal. After the response  824  and notification  826 , the IFF routine exits. 
     If the incoming IFF interrogation/signal is not the second type, a test  810  is made to determine if the incoming IFF interrogation/targeting signal is a third type, and, if so, a specific response is made  828  and a specific notification is made  830 . An example of a response made  828  is a specific pattern of flashing of the indicators  58   c  that are not visible to the naked eye. An example of a notification  830  is a specific sequence of vibrations at, for example, the vibratory pad  104  and/or illumination of the status indicator  59 . The notifications  830  provide the wearer with an indication that the wearer is being interrogated. After the response  828  and notification  830 , the IFF routine exits. 
     Note that it is fully anticipated that configuration parameters and specific programming of the marker system  10  provide for factory and/or field programming of the IFF interrogation/targeting signal protocols, security codes, parameters, etc., such that, in some embodiments, the IFF interrogation/targeting signals recognized by the marker system  10  are established during manufacture and/or during field operations. Further, it is fully anticipated that configuration parameters regarding specific response signaling and/or notification signals are also factory and/or field programmed as needed. It is also anticipated that, in some embodiments, there are no IFF interrogation/targeting signal capabilities and/or the IFF interrogation/targeting signal are disabled. 
       FIG. 14  shows one example of software for wired or wireless programming or re-programming the marker system  10 . The marker system  10  is programed or re-programed in the factory or in the field. This software is run when the operating status confirmation switch  120  is held for a specific period of time, for example, for five seconds. (In another embodiment, sequencing of the other switches could initiate the programming sequence). The programming starts with a loop that detects if a programming signal is being received  900  and, if not, checks to see it a certain amount of time has elapsed  902  (e.g., 20 seconds). If the time has elapsed  920 , the programming routine finishes and will need to be repeated again later if programming is desired. 
     Once the programming signal start is detected  900 , the programming is received  904  then it is determined  906  if the programming that was received is a new program or a set of new parameters. If the programming is a set of new parameters, each parameter is set  930  until a test is made determining that there are no more new parameters  932 , at which time the parameters are set into flash memory  934  and the programming ends. If the programming is a new program (e.g. an update to the operating program of the marker system  10 ), the new program is loaded  908  and copied into flash memory a block at a time  910  until a test is made determining that there are no more blocks to be copied  912 , at which time the flashing ends  914  and the programming ends. 
     In some embodiments, it is anticipated that the programming includes setting the encoding algorithms for the Identification Friend or Foe (IFF) and for the munitions-targeting signal. In such, it is also anticipated that the programming includes setting the wavelength(s) for the Identification Friend or Foe (IFF) and for the munitions-targeting signal; setting the wavelength(s) for the responses, setting the patterns for the notification signals, configuring the operation of any switches that are present, etc. 
     The above shows on exemplary set of programs operating on the controller  200  and is intended as an example, as many other programs are fully anticipated and the examples shown are in no way meant to limit the marker system  10  in any way. 
     Referring to  FIG. 15 , a view of an exemplary cellphone  1000  communicating with the marker system  10  is shown. As it is important for the combatant  1120  (see  FIG. 17 ) to know when they are entering a danger zone  1100 , the marker system  10  needs to have access to positioning data. There are several known ways to provide position data including triangulation and using the satellite global positioning system. As the marker system  10  is anticipated for use in locations lacking cellular service or having unknown cellular tower locations, triangulation is not the preferred source of positioning data. Therefore, although triangulation is anticipated, use of the satellite global positioning system is described. 
     It is anticipated that positioning data be obtained from the satellite global positioning system from either of a local GPS receiver  196  (see  FIG. 9 ) or from a GPS receiver  1091  of a nearby cell phone  1000  (see  FIG. 16 ). The positioning data is periodically read from the local GPS receiver  196  or from a GPS receiver  1091  of a nearby cell phone  1000  and used to determine the location of the combatant  1120  with respect to any known danger zones  1100 . In  FIG. 15 , the positioning data is read from a GPS receiver  1091  of a nearby cell phone  1000 . It is anticipated that the positioning data is then analyzed within the cell phone  1000  or the positioning data is transmitted to the marker system  10  where the positioning data is then analyzed within the marker system. In embodiments in which the positioning data is analyzed within the cell phone  1000 , if it is determined that the combatant  1120  is within a danger zone  1100 , an indication of such is transmitted to the marker system  10 . In embodiments in which the positioning data is analyzed within the marker system  10 , the positioning data is periodically transmitted from the cell phone  1000  to the marker system  10  for analysis. In all embodiments, it is anticipated that the transmission is performed over any wired connection (e.g. USB) or a wireless connection (e.g. Bluetooth or Wi-Fi). 
     Once it is determined that the combatant  1120  is within a danger zone  1100 , the marker system  10  provides a signal to the vibratory pad  104  to warn the combatant  1120  of the eminent danger. In some embodiments in which the positioning data is analyzed within the marker system  10 , if it is determined that the combatant  1120  is within a danger zone  1100 , the marker system  10  transmits a signal to the cell phone  1000  and the cell phone  1000  takes appropriate action such as vibrating, displaying a message, transmitting an SMS message, etc. 
     As danger zones  1100  vary with troop movements, enemy positioning, clearing of mine fields, changes to the fields of target by aircraft, etc., it is anticipated that the coordinates of the danger zone(s)  1100  be loaded into a memory. In embodiments in which the positioning data is analyzed within the cell phone  1000 , the coordinates of the danger zone  1100  are loaded onto a memory  1074  of the cell phone (or other device having global positioning system—GPS). In embodiments in which the positioning data is analyzed within the marker system  10 , the positioning data is periodically transmitted to the marker system  10  for analysis against coordinates of danger zones  1100  that are stored in a memory accessible by the controller  200 . 
     Referring to  FIG. 16 , a schematic view of an exemplary cellphone  1000  is shown. Although any device(s) is/are anticipated that communicate with the marker system  10 , for clarity purposes, a cell phone  1000  will be used in the remainder of the description. 
     Again, although a cell phone  1000  is used in the description, the present invention is in no way limited to using a cell phone  1000  as any computational device (typically processor-based, but not required to have a processor) is anticipated (e.g., a tablet computer, a smart watch, etc.). 
     The example cell phone  1000  represents a typical device that exchanges information with the marker system  10 . An exemplary cell phone  1000  is shown for clarity reasons as different architectures are known that accomplish similar results in a similar fashion and the present invention is not limited in any way to any particular cell phone  1000  system architecture or implementation. In this exemplary cell phone  1000 , a processor  1070  executes or runs programs loaded in a random-access memory  1075 . The programs are generally stored in persistent memory  1074  and loaded into the random-access memory  1075  when needed. Also, accessible by the processor  1070  is a SIM (subscriber information module) card  1088  having subscriber identification encoded there within and often a small amount of persistent storage. The processor  1070  is any processor, typically a processor designed for cell phones  1000 . The persistent memory  1074 , random-access memory  1075 , and SIM card are connected to the processor by, for example, a memory bus  1072 . The random-access memory  1075  is any memory suitable for connection and operation with the selected processor  1070 , such as SRAM, DRAM, SDRAM, RDRAM, DDR, DDR-2, etc. The persistent memory  1074  is any type, configuration, capacity of memory suitable for persistently storing data, for example, flash memory, read only memory, battery-backed memory, etc. In some exemplary cell phones  1000 , the persistent memory  1074  is removable, in the form of a memory card of appropriate format such as SD (secure digital) cards, micro SD cards, compact flash, etc. 
     Also connected to the processor  1070  is a system bus  82  for connecting to peripheral subsystems such as a cellular network interface  1080 , a graphics adapter  84  and a touch screen interface  1092 . The graphics adapter  1084  receives commands from the processor  1070  and controls what is depicted on the display  86 . The touch screen interface  1092  provides navigation and selection features. 
     In general, some portion of the persistent memory  1074  and/or the SIM card  1088  is used to store programs, executable code, and data, etc. In some embodiments, other data is stored in the persistent memory  1074  such as audio files, video files, text messages, etc. 
     The peripherals are examples and other devices are known in the industry such as Global Positioning Subsystem  1091 , speakers (not shown), USB interfaces, camera(s)  1093  (front and back facing), microphone  1095 , Bluetooth transceiver  1094 , and Wi-Fi transceiver  1096 . 
     The cellular network interface  1080  connects the cell phone  1000  to the cellular network  68  through any cellular band and cellular protocol such as GSM, TDMA, LTE, etc., through a wireless medium  1078 . There is no limitation on the type of cellular connection used. The cellular network interface  1080  provides voice call, data, messaging services as well as Internet access to the cell phone  1000  through the cellular network  1068 . 
     For local communications, many cell phones  1000  include a Bluetooth transceiver  1094 , a Wi-Fi transceiver  1096 , or both and some cell phones  1000  support other network schemes as well, such as including near-me and body area networks. Such features of cell phones  1000  provide data communications between the cell phones  1000  and data access points and/or other computers such as the marker system  10 . 
     Referring to  FIG. 17 , a combatant  1120  entering a danger zone  1100  is shown. Again, as it is important for the combatant  1120  to know when they are entering a danger zone  1100 , the marker system  10  needs to have access to positioning data. Although it is anticipated that there are many danger zones  1100 , a single danger zone  1100  is shown for brevity and clarity. 
     Although a simple danger zone  1100  is a rectangular shape or circular shape, there is no restriction as to the size or shape of a danger zone  1100 , as for example, roads where dangers of Improvised Explosive Devices (IEDs) or mine fields do not have regular shapes. 
     The danger zone  1100  shown in  FIG. 17  includes a warning boundary  1104  and a danger boundary  1106 , though it is fully anticipated that some danger zones  1100  include only a danger boundary  1106  or only a warning boundary  1104 . In the scenario shown, the combatant  1120  has crossed the warning boundary  1104 . Using the positioning data the marker system  10  with or without the help of the cell phone  1100  determines that the combatant  1120  is within the warning boundary  1104  and, depending upon configuration, notifies the combatant  1120  of such, for example, by vibrating the vibratory pad  104  in a first pattern. If the combatant  1120  continues and crossed the danger boundary  1106 , the marker system  10  with or without the help of the cell phone  1100  determines that the combatant  1120  is within the danger boundary  1106  and, depending upon configuration, the marker system  10  notifies the combatant  1120  of such, for example, by vibrating the vibratory pad  104  in a second pattern. It is also anticipated that as the combatant  1120  exits either the warning boundary  1104  or the danger boundary  1106 , the marker system  10  notifies the combatant  1120  of such, for example, by vibrating the vibratory pad  104  in a third pattern. 
     The coordinates of the warning boundary  1104  and/or the danger boundary  1106  for each danger zone  1100  are loaded into either the marker system  10  or the cell phone  1000  through wired or wireless transmission. In some embodiments, the coordinates of the warning boundary  1104  and/or the danger boundary  1106  for each danger zone  1100  are loaded into either the marker system  10  or the cell phone  1000  during an operation through wireless transmission as updated danger zones  1100  are posted during the operation. 
     As the amount of data storage and processing required to maintain many danger zones  1100  and to analyzed a current location from positioning data is high, it is anticipated that it will be preferred that the positioning data be obtained from a GPS receiver  1091  of a nearby cell phone  1000 . In this, maps of the danger zones  1100  are stored in memory of the cell phone  1000 . The positioning data is periodically read from the GPS receiver  1091  of the cell phone  1000  and software running on the cell phone uses the maps of danger zones  1100  to determine the location of the combatant  1120  with respect to any of the danger zones  1100 . If it is determined by this software that the combatant  1120  is within a danger zone  1100 , an indication of such is transmitted from the cell phone  1000  to the marker system  10  over a wired connection (e.g. USB) or a wireless connection (e.g. Bluetooth or Wi-Fi). Responsive to this indication, the marker system  10  provides a signal to the vibratory pad  104  to warn the combatant  1120  of the eminent danger. In some embodiments in which the positioning data is analyzed within the cell phone  1000 , if it is determined that the combatant  1120  is within a danger zone  1100 , the cell phone  1000  also takes appropriate action such as vibrating, displaying a message, transmitting an SMS message, etc. 
     Additionally, by including the cell phone  1000 , in some embodiments, detailed records of the combatant&#39;s  1120  path of travel are recorded for various purposes. For example, should the combatant  1120  take notes of certain devices or activities (e.g. enemy movement or locating an IED or land mine), the location of such will be within the stored record of the combatants  1120  travel. 
     Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
     It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.