Communication device in which an unauthorized removal of an electrical connector is detected

Systems (100) and methods (1400) for detecting removal and attempted removals of an electronic component from an electronic device. The methods comprising: disposing the electronic component (112) on the electronic device such that a conductive surface of the electronic component contacts a ground conductor (802) disposed on a first surface (812) of an internal circuit board (500); using an electro-mechanical member (700) to mechanically couple the electronic component to the internal circuit board and to create an electrical path from the ground conductor to a sensing conductor (800) disposed on a second surface (814) opposed from the first surface of the internal circuit board; and sensing a break in the electrical path.

BACKGROUND OF THE INVENTION

Statement of the Technical Field

The inventive arrangements relate to communication devices. More particularly, the invention concerns communication devices in which an unauthorized removal of an electrical connector is detected.

DESCRIPTION OF THE RELATED ART

There are many communication devices known in the art. At least one of these communication devices implements a means to detect when an electrical connector has been decoupled therefrom. This means includes a Commercial Off The Shelf (“COTS”) switch. When the electrical connector is coupled to the communication device, a button of the switch is depressed thereby. The button is released upon decoupling of the electrical connector from the communication device. In this way, the communication device can detect when a malicious attempt to obtain access to the internal circuitry of the communication device occurs by forcefully removing the electrical connector therefrom.

Despite the advantages the COTS switch arrangement, it suffers from certain disadvantages. For example, actuation of the COTS switch may occur in response to shock and/or vibration applied thereto and/or to the communication device. Also, the COTS switch is relatively costly and has certain Design For Manufacturing (“DFM”) issues associated therewith. The DFM issues relate to the tight tolerances needed to ensure applicable plunger actuation ranges.

SUMMARY OF THE INVENTION

The present invention concern systems and methods for detecting removal and attempted removals of an electronic component (e.g., an input/output connector for an accessory) from an electronic device (e.g., a manpack radio). The methods involve: disposing the electronic component on the electronic device such that a conductive surface of the electronic component contacts a ground conductor disposed on a first surface of an internal circuit board; using an electro-mechanical member to mechanically couple the electronic component to the internal circuit board and to create an electrical path from the ground conductor to a sensing conductor disposed on a second surface opposed from the first surface of the internal circuit board; and sensing a break in the electrical path.

The break in the electrical path is detected when a voltage supplied to a detector circuit of the electronic device is higher as compared to a voltage supplied to the detector circuit when the electrical path is not broken. The voltage change may occur when the electro-mechanical member breaks in response to an application of a force to the electronic component. Additionally or alternatively, the voltage change may occur when a first portion of the internal circuit board adjacent to the sensing conductor breaks away from a remaining second portion of the internal circuit board, in response to an application of a force to the electronic component.

In some scenarios, the electro-mechanical member comprises a screw that passes through an aperture formed through the internal circuit board and threadingly engages a mounting aperture formed in the electronic component. The screw is selected to break under a first tensile load which is lower as compared to a tensile load needed for breaking a coupler used to mechanically couple the electronic component to a housing of the electronic device.

DETAILED DESCRIPTION

OVERVIEW

The present invention concerns systems and methods for detecting a forceful removal of an electronic component from a communication device. The methods involve: disposing an electronic component on an electronic device such that a conductive surface of the electronic component contacts a ground conductor disposed on a first surface of an internal circuit board; using an electro-mechanical member to mechanically couple the electronic component to the internal circuit board and to create an electrical path from the ground conductor to a sensing conductor disposed on a second surface opposed from the first surface of the internal circuit board; and sensing a break in the electrical path.

Notably, the present invention overcomes various drawbacks of conventional systems, such as that disclosed in the background section of this document. For example, the electro-mechanical techniques used herein, to detect the forceful removal of an electronic component from the communication device, eliminate the need for COTS switches. Therefore, the present invention provides a detection means which is less costly, more reliable and easier to manufacture than that of the conventional systems.

Communication Device

Referring now toFIGS. 1-2, there is provided a schematic illustration of an exemplary communication device100that is useful for understanding the present invention. The communication device100is shown as comprising a portable manpack radio or man-portable, tactical software defined combat-net radio covering a predefined (e.g., 30-512 MHz) frequency range. The present invention is not limited in this regard. The communication device can alternatively comprise any type of communication device in which forceful attempts to remove an electronic component (e.g., an I/O connector) therefrom needs to be detected.

As shown inFIGS. 1-2, the communication device100comprises a housing106in which various electronic components are housed. The electronic components include, but are not limited to, transceivers, filters, switches, processors, data stores, and other hardware. The listed electronic components are well known in the art, and therefore will not be described herein. One or more of the listed electronic components may be disposed on a PCB housed inside the housing106. A schematic illustration of a PCB500disposed in the housing106is provided inFIG. 5.

The communication device100also comprises various Input/Output (“I/O”) components. For example, as shown inFIGS. 1-2, various I/O components116-120are also disposed on a front panel122of the communication device100. The I/O components116-120include a display screen116, a keypad118, a knob120, and a plurality of I/O connectors124,126. These I/O components116-120facilitate user-software interactions for controlling operations of the communication device100.

A number of I/O components110,112,114are also disposed on a top panel108of the housing106. The I/O components110-114include electronic connectors for accessories. As such, the I/O components110,112,114facilitate the attachment and detachment of accessories to the communication device100. The accessories may include antennas, handsets, global positioning devices, external memory, testing modules, calibration modules, and lights. In this regard, the I/O components110,112,114are coupled to the PCB500disposed in the housing106so as to connect an attached accessory to the internal circuitry of the communication device100.

Schematic illustrations of an exemplary architecture for I/O connector112are provided inFIGS. 3-4. Each I/O component110and114is the same as or substantially similar to I/O connector112. As such, the discussion of I/O connector112is sufficient for understanding I/O components110and114.

As shown inFIGS. 3-4, the I/O connector112comprises a body302with four apertures304,306,308,310formed therethrough. These apertures304-310are provided to facilitate (a) the mechanical mounting of the I/O connector112on an external surface of the communication device housing106via mounting screws and (b) the formation of an environmental seal between the I/O connector112and the housing106. The environmental seal is at least partially achieved using a piston sealing member408disposed on the body302of the I/O connector112. Piston sealing members are well known in the art, and therefore will not be described herein.

An accessory interface312is provided on the body302to which an electronic connector of an accessory can be coupled. Accessory interfaces are well known in the art, and therefore will not be described herein. Any known or to be known accessory interface that is suitable for a particular application can be used herein without limitation.

Two mounting apertures402,404are formed on a bottom panel406of the body302. These mounting apertures402,404are provided to facilitate the coupling of at least one electro-mechanical detection mechanism to the I/O connector112such that a forceful detachment thereof from the housing can be detected. Exemplary electro-mechanical detection mechanisms will be described in detail below. Still, it should be understood that such electro-mechanical detection mechanisms comprise at least one screw which passes through an aperture502formed in the PWB500disposed in the communication device.

Referring now toFIGS. 6-7, there are provided schematic illustrations that are useful for understanding how the I/O components110-114are coupled thereto such that the forceful removal thereof may be detected. In the present case, an electro-mechanical detection mechanism600is used for making such detection. The electro-mechanical detection mechanism600will be discussed herein in relation to I/O component112. The same or similar electro-mechanical detection mechanism is used with I/O components110and114.

The electro-mechanical detection mechanism600comprises an elongate electro-mechanical member700which passes through the PWB500into a mounting aperture404. In this way, the electro-mechanical member700contacts both the PWB500and a mechanical-electrical contact702of the I/O component112. The mechanical-electrical contact702comprises threads704formed on an inner surface706of the mounting aperture404. Accordingly, the electro-mechanical member700has corresponding threads708formed on an outer surface thereof for mechanically engaging the threads704of the mounting aperture404. In some scenarios, the electro-mechanical member700comprises a screw.

As should be understood, the communication device100has certain size requirements. Thus, the electro-mechanical member700is selected to have as small as size as possible so as to minimize the amount of space needed therefore inside the communication device100.

If the mechanical aspects of the electro-mechanical member700are only relied upon, then an external screw having more tension force than the electro-mechanical member700(when it comes to the shear strength thereof) could be used to break the internal electro-mechanical member700. This is evident from the following discussion.

Mathematical Equation (1) provides a way to compute the load needed to break the threaded part of a #6-32 screw. Mathematical Equation (2) provides a way to compute the load needed to break a threaded part708of a #2-56 screw.
P=σy·At=913.88 lbs  (1)
P=σy·At=295.70 lbs  (2)
P represents the direct axial tensile load to break a threaded portion of a screw. This is a maximum Von Mises stress comprised of the principle stresses and shear (torsional stresses) that are not calculated here.

If the electro-mechanical member700is selected to comprise a #2-56 screw, a user could remove the I/O component112simply by applying enough force to the outside of the I/O component112so as to cause breaking of the internal electro-mechanical member700. This force can be applied using a #6-32 screw coupled to the I/O component112via the accessory interface312. Once the I/O component112has been removed, the user could tamper with the internal circuitry of the communication device100. Thereafter, the I/O component112could then be mounted once again to the communication device100via the four external mounting screws. In this scenario, such tampering of the communication device100would not be detected.

Therefore, in addition to the mechanical aspects of the electro-mechanical member700, the present invention relies upon the conductive aspects thereof. The conductive aspects of the electro-mechanical member700facilitate the provision of a means to detect a breaking thereof. This will become more evident from the following discussion ofFIGS. 8-9.

As shown inFIG. 8, a ground connection802to the I/O component112is electrically detected through the electro-mechanical member700. In this regard, a grounded conductor808is disposed on a first surface812of the PCB500. The grounded conductor808is in electrical contact with a conductive surface810of the I/O component112. The conductive surface810is also in electrical contact with the electro-mechanical member700. The electro-mechanical member700electrically contacts a sensing conductor800disposed on a second surface814of the PCB500. The sensing conductor800and a pull-up resistor804are coupled to a detector806. The detector806comprises software and/or hardware configured to sense when current flows through or ceases flowing through the electro-mechanical member700.

When the electro-mechanical member700breaks, there will no longer be continuity between the sensing conductor800and ground, as shown inFIG. 9. In this case, the detector806senses a high pull-up voltage signal. When such detection occurs, the detector806determines that the electro-mechanical member700has been broken, and therefore the I/O component112may have been removed from the communication device100by an unauthorized and/or malicious individual. Upon such a determination, the detector806performs certain remedial measures.

The present invention is not limited to the detection technique described above for detecting when the I/O component has been removed from the communication device. Other detection techniques can be employed. For example, in addition to or alternative to the above described, detection technique, another detection technique can be employed which uses perforations1002in the PCB for causing a circuit trace thereof to break in response to the shearing of the electro-mechanical member. The particulars of this perforation based detection technique will become more evident as the discussion progresses. Still, it should be understood that the load required to break the PCB (based on the PCB thickness) is less than the load required to break the electro-mechanical member of the electro-mechanical detection mechanism. Thus, when a force is applied externally to the I/O connector the PCB will break instead of the electro-mechanical member.

Referring now toFIGS. 10-11, there is provided schematic illustrations that are useful for understanding how the I/O components110-114are coupled to a communication device such that the forceful removal thereof may be detected in accordance with a perforation based detection technique. In the present case, an electro-mechanical detection mechanism1100is used for making such detection. The electro-mechanical detection mechanism1100will be discussed herein in relation to an I/O component1150. The same or similar electro-mechanical detection mechanism may also be used with I/O components110-114. As such, I/O component1150is the same as or similar to I/O components110-114. Thus, the discussion provided above in relation to I/O components110-114is sufficient for understanding I/O component1150.

The electro-mechanical detection mechanism1100comprises an elongate electro-mechanical member1102which passes through the PWB1000into a mounting aperture1104. In this way, the electro-mechanical member1102contacts both the PWB1000and a mechanical-electrical contact1106of the I/O component1150. The mechanical-electrical contact1106comprises threads1108formed on an inner surface1110of the mounting aperture1104. Accordingly, the electro-mechanical member1100has corresponding threads1112formed on an outer surface thereof for mechanically engaging the threads1108of the mounting aperture1104. In some scenarios, the electro-mechanical member1100comprises a screw.

As shown inFIG. 12, a ground connection1202to the I/O component1150is electrically detected through the electro-mechanical member1102. In this regard, a grounded conductor1208is disposed on a first surface1212of the PCB1000. The grounded conductor1208is in electrical contact with a conductive surface1210of the I/O component1150. The conductive surface1210is also in electrical contact with the electro-mechanical member1100. The electro-mechanical member1100electrically contacts a sensing conductor1200disposed on a second surface1214of the PCB1000. The sensing conductor1200and a pull-up resistor1204are coupled to a detector1206. The detector1206senses when current flows through the electro-mechanical member1100towards the detector1206.

The PCB1000may be broken at point1250simply by applying enough force to the outside of the I/O component1150. This force can be applied using a #6-32 screw coupled to the I/O component1150via the accessory interface thereof. When the PCB1000is broken at point1250, there will no longer be continuity between the sensing conductor1200and the detector1206, as shown inFIG. 13. In this case, the detector1206senses a high pull-up voltage signal. When such detection occurs, the detector1206determines that the PCB1000has been broken, and therefore the I/O component1150may have been removed from the communication device by an unauthorized and/or malicious individual. Upon such a determination, the detector1206performs certain remedial measures.

Exemplary Method

Referring now toFIG. 14, there is a flow diagram of an exemplary method1400for detecting removal of an electronic component (e.g., I/O component112ofFIG. 1 or 1150ofFIG. 11) from an electronic device (e.g., communication device100ofFIG. 1). The method1400begins with step1402and continues with step1404. In step1404, the electronic component is disposed on the electronic device such that a conductive surface of the electronic component contacts a ground conductor (e.g., ground conductor802ofFIG. 8 or 1202ofFIG. 12) disposed on a first surface (e.g., surface810ofFIG. 8 or 1210ofFIG. 12) of an internal circuit board (e.g., PCB500ofFIG. 5 or 1000ofFIG. 10). Next in step1406, an electro-mechanical member (e.g., electron-mechanical member700ofFIG. 7 or 1102ofFIG. 11) is used to mechanically couple the electronic component to the internal circuit board. The electro-mechanical member is also used to create an electrical path from the ground conductor to a sensing conductor (e.g., conductor800ofFIG. 8 or 1200ofFIG. 12) disposed on a second surface (e.g., surface814ofFIG. 8 or 1214ofFIG. 12) opposed from the first surface of the internal circuit board. Upon completing step1406, step1408is performed where a break in the electrical path is sensed. One or more remedial measures may then be performed, as shown by optional step1410. Thereafter, step1412is performed where method1400ends.

In some scenarios, the break in the electrical path is detected when a voltage supplied to a detector circuit of the electronic device is higher as compared to a voltage supplied to the detector circuit when the electrical path is not broken. The voltage change may occur when the electro-mechanical member breaks in response to an application of a force to the electronic component. Additionally or alternatively, the voltage change may occur when a first portion of the internal circuit board adjacent to the sensing conductor breaks away from a remaining second portion of the internal circuit board, in response to an application of a force to the electronic component.

In those or other scenarios, the electro-mechanical member comprises a screw that passes through an aperture formed through the internal circuit board and threadingly engages a mounting aperture formed in the electronic component. The screw is selected to break under a first tensile load which is lower as compared to a tensile load needed for breaking a coupler used to mechanically couple the electronic component to a housing of the electronic device.

Although the invention has been illustrated and described with respect to one or more implementations, equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Thus, the breadth and scope of the present invention should not be limited by any of the above described embodiments. Rather, the scope of the invention should be defined in accordance with the following claims and their equivalents.