Radio with tamper protection

Abstract

A radio device (10) with tamper protection is described. The radio device (10) comprises a housing (14). The housing (14) comprises a first housing part (22) and a second housing part (24), which are movable relative to one another. The contact mechanism (28) comprises a first contact (30), a second contact (32), and an electrically insulating separating element (34). The separating element (34) is connected to the second housing part (24) such that the separating element (34) is removable from the contact area between the first contact (30) and the second contact (32) when the second housing part (24) is moved relative to the first housing part (22), whereby the first contact (30) and the second contact (32) come into contact with one another. A processing circuit (26) is connected to the contact mechanism (28) and configured to execute a response when the first contact (30) and the second contact (32) come into contact with one another.

Description

[0001] The invention relates to a radio device with tamper protection.

[0002] Radio devices enable wireless communication and are also used for the exchange of confidential information. If such a radio device falls into the hands of an unauthorized person, it should be prevented from being used to participate in the confidential exchange of information. It should also be prevented that confidential information stored in the radio device can be read, for example, to decrypt encrypted communication.

[0003] Tamper protection measures include detection if the device's housing is opened. Various state-of-the-art measures are known for detecting unauthorized opening. One example is a detection circuit in conjunction with a switch. To prevent current from flowing through the detection circuit when the housing is closed, thus preventing energy consumption, the use of a normally open switch is recommended. With normally closed switches, a contact connection is established when they are activated.

[0004] One challenge is that the switch must switch reliably, even when the housing is only slightly opened, but at the same time unwanted switching must be avoided, for example when the radio is exposed to vibrations or shocks.

[0005] Tamper protection generally ensures that after switching, the functionality of the radio is restricted, typically shutting down communication. However, radios are often used for purposes where important information must be transmitted quickly. Accordingly, incorrect switching and the resulting loss of communication can lead to undesirable consequences.

[0006] It is a significant effort and expense to provide a device that reliably detects when the housing has been opened, yet prevents accidental switching due to vibration or shock. Switches with increased reliability require a larger installation volume, which limits the possibilities for providing a compact radio device. Compact external dimensions are particularly important for handheld radios, ensuring the device is user-friendly and mobile.

[0007] The object of the invention is to provide a radio device having a tamper protection with which an opening of the device housing is reliably detected but false triggering is avoided, wherein the tamper protection is to be implemented in the most space-saving and cost-effective way possible.

[0008] This object is achieved according to the invention by a radio device with tamper protection. The radio device comprises a housing in which a transmitter circuit and / or a receiver circuit, a processing circuit, and a contact mechanism for detecting a tamper attempt are provided. The housing comprises a first housing part and a second housing part, which are movable relative to one another to transfer the housing from a closed state to an open state.

[0009] The contact mechanism comprises a first contact, a second contact, and an electrically insulating separating element. When the housing is closed, the separating element is arranged in a contact area between the first contact and the second contact such that (electrical) contact between the first contact and the second contact is prevented.

[0010] The separating element is connected to the second housing part such that the separating element is removable from the contact area between the first contact and the second contact when the second housing part is moved relative to the first housing part, whereby the first contact and the second contact come into (electrical) contact with each other.

[0011] The processing circuit is connected to the contact mechanism and is configured to perform a reaction when the first contact and the second contact come into contact with each other, i.e. when electrical contact is established between the first contact and the second contact.

[0012] The insulating separator between the two contacts prevents false triggering when the radio is exposed to shocks or vibrations, for example. The separator ensures isolation between the contacts in an initial position, which allows the distance traveled by the separator to trigger the contact mechanism to be kept particularly short. This reduces the requirements for the housing's mechanical tolerances without compromising the reliability of the triggering.

[0013] Compared to conventional switches, the contact mechanism according to the invention has a smaller installation volume and weight. Furthermore, the contact mechanism is particularly simple to construct, as it consists of a smaller number of components and components of less complexity than a conventional switch.

[0014] The reaction executed by the processing circuitry may result in a restriction of the radio's functionality. This can prevent an unauthorized person from participating in the communication and / or reading data.

[0015] In particular, the response includes deleting data from the radio's data storage. This ensures protection against unauthorized access to confidential data or content.

[0016] An energy storage device can be arranged in the housing, which is connected to at least one of the contacts. The energy storage device is, in particular, an electrochemical primary battery or an electrochemical accumulator. By arranging the energy storage device in the housing, it can be ensured that the power supply for the tamper protection is protected from interference by unauthorized persons.

[0017] The processing circuit can be a passive circuit that is supplied with power when the first and second contacts come into contact, i.e., when electrical contact is established between the first and second contacts. A current flow thus only occurs if the housing is opened without authorization, allowing the tamper protection to operate particularly energy-efficiently.

[0018] In some embodiments, the radio device may include a cryptographic circuit for encrypting and / or decrypting information, which is arranged in the housing. Thus, incoming data can be decrypted, or outgoing data can be encrypted. This enables encrypted voice transmission and / or data transmission. The processing unit may be configured to delete a corresponding cryptographic key from the data memory of the radio device when the first contact and the second contact come into contact with each other. Participation in the confidential communication by an unauthorized person can thus be prevented.

[0019] The radio is primarily a handheld radio. The space-saving contact mechanism is particularly advantageous for a handheld radio, as it allows the device to be constructed with compact external dimensions. This makes the radio particularly user-friendly and suitable for mobile use.

[0020] The second housing part is, in particular, a cover of the radio device. The radio device can be designed such that removing the cover is the only way to non-destructively open the housing and access the components contained therein. This makes circumventing the tamper protection by opening the housing in any other way more difficult. The first housing part is, in particular, formed in one piece. The housing preferably consists of only two housing parts, namely the first housing part and the second housing part.

[0021] In addition, the housing can be designed such that the distance that must be covered through the second housing part to reach the interior of the housing is greater than the distance that the separating element travels when it is removed from the contact area when the housing is opened. This prevents circumvention of the tamper protection by only slightly opening the housing.

[0022] The second housing part can include a fastening mechanism for the separator, via which the separator is attached to the second housing part. This provides a mechanism for securing the end of the separator to the second housing part after the other end of the separator has been positioned between the two contacts. This enables easy installation and commissioning of the tamper protection.

[0023] The fastening mechanism can comprise a recess in the second housing part, wherein one end of the separating element is inserted into the recess, in particular glued in. Thus, the end can be inserted into the recess and in particular glued in after the other end of the separating element has been positioned in the contact area.

[0024] Alternatively or additionally, the fastening mechanism may comprise a clamping bracket comprising a spring for clamping the separating element. This allows the end of the separating element to be clamped to the second housing part after the other end of the separating element has been positioned in the contact area.

[0025] In embodiments, an end portion of the first contact and / or an end portion of the second contact may have a curvature configured such that a respective end of the first contact and / or the second contact points away from the other contact. Thus, a contact mechanism can be provided in which the removal of the separating element from the contact area is reversible, since the separating element can be easily pushed back between the contacts. This makes it possible to provide a radio device that can be restored to a normal, functional state by an authorized person after the contact mechanism has been triggered, particularly quickly and without great effort.

[0026] Alternatively, an end section of the first contact or an end section of the second contact can be designed such that the end of the contact rests on the surface of the other contact. This can provide a contact mechanism in which the separating element is guided past the contact area when the housing is resealed. This can prevent an unauthorized person from reversing the triggering of the contact mechanism by resealing the housing.

[0027] According to one aspect, at least the first contact and / or the second contact can be mechanically preloaded so that the first contact and the second contact come into mechanical contact with each other when the separating element has been removed from the contact area between the first contact and the second contact. This makes it possible to provide a particularly space-saving and easy-to-implement contact mechanism that ensures that the two contacts contact each other when the separating element has been removed.

[0028] Alternatively or additionally, at least one preloaded spring can be provided in the contact mechanism, which exerts a corresponding force on the first contact or the second contact. This can be a coil spring, for example. By using a spring, a high force can be exerted on the corresponding contact, which can further improve the reliability of the triggering.

[0029] Further advantages and features of the invention will become apparent from the following description and the drawings, to which reference is made. In the drawings: - Fig. 1 a schematic representation of a radio device according to the invention, - Fig. 2 a schematic sectional view of a radio device according to the invention with a closed housing, - Fig. 3 a schematic sectional view of a radio device according to the invention with a partially opened housing, - Fig. 4 a schematic representation of the contact mechanism of a radio device according to the invention in a first embodiment and - Fig. 5 a schematic representation of the contact mechanism of a radio device according to the invention in a further embodiment.

[0030] Fig. Figure 1 shows a schematic representation of a radio device 10 according to the invention with tamper protection. This is, in particular, a handheld radio device.

[0031] In the example shown, a (removable) antenna 12 is installed on the radio device 10, which can be rotated out, for example. The radio device 10 comprises a housing 14 in which, among other things, a transmitter circuit 16 is provided.

[0032] Alternatively or in addition to the transmitter circuit 16, a receiver circuit may be provided. As a further alternative, a transceiver circuit, i.e., a circuit with combined transmitter and receiver functionality, may be provided instead of the transmitter circuit 16. In general, in the context of the present invention, a circuit is understood to mean, in particular, an electronic circuit.

[0033] In addition, the radio device 10 may include a cryptography circuit 18 for encrypting and / or decrypting data or information, which is arranged in the housing 14. In particular, the cryptography circuit 18 is connected to the transmitter circuit 16.

[0034] Furthermore, the radio device 10 may include a data memory 20 connected to the cryptography circuit 18. At least one cryptographic key may be stored in the data memory 20.

[0035] The data memory 20 may be a separate memory that exclusively contains the cryptographic key in encrypted form. Alternatively, the cryptography circuit 18 may have such a separate memory.

[0036] The housing 14 comprises a first housing part 22 and a second housing part 24, which are movable relative to one another to transfer the housing 14 from a closed state, which can also be considered the initial state, to an open state. The second housing part 24 is, in particular, a cover of the radio device 10.

[0037] Fig. Figure 2 is a schematic sectional view of a radio device 10 according to the invention with a closed housing 14. It can be, for example, the Fig. 1. A processing circuit 26 and a contact mechanism 28 for detecting a tampering attempt are provided in the housing 14.

[0038] The contact mechanism 28 comprises a first contact 30, a second contact 32 and an electrically insulating separating element 34. In the closed state of the housing 14, the separating element 34 is arranged in a contact area between the first contact 30 and the second contact 32 such that an (electrical and / or mechanical) contact between the first contact 30 and the second contact 32 is prevented.

[0039] The separating element 34 is connected to the second housing part 24 such that the separating element 34 is removable from the contact area between the first contact 30 and the second contact 32 when the second housing part 24 is moved relative to the first housing part 22, whereby the first contact 30 and the second contact 32 come into (electrical and / or mechanical) contact with each other.

[0040] In this case, the first contact 30 and / or the second contact 32 can be mechanically prestressed so that the first contact 30 and the second contact 32 come into mechanical contact with each other when the separating element 34 has been removed from the contact area between the first contact 30 and the second contact 32.

[0041] A schematic sectional view of the radio device 10 with the housing 14 partially opened is shown in Fig. 3. Here, the separating element 34 is located outside the contact area, and the first contact 30 and the second contact 32 are in mechanical and electrical contact with each other. In particular, the (mechanical and electrical) contact has already been established, even though the second housing part 24 has not yet been completely removed from the first housing part 22.

[0042] As in Fig. 3, the path that must be traveled through the second housing part 24 in order to reach the interior of the housing 14 is greater than the path that the separating element 34 travels when it is removed from the contact area when the housing 14 is opened.

[0043] In other words, the contact between the contacts 30, 32 is already established before the second housing part 24 has been moved relative to the first housing part 22 to such an extent that access to the interior of the housing 14 is possible.

[0044] In the present example, this is achieved by the second housing part 24 being recessed into the first housing part 22 at a corresponding depth when the housing 14 is closed (see Fig. 2). The first housing part 22 may have a projection 35 in its interior, for example in the form of a shoulder portion, on which the second housing part 24 rests after the housing 14 is closed.

[0045] The processing circuit 26 is connected to the contact mechanism 28 and configured to execute a response when the first contact 30 and the second contact 32 come into contact with each other, thereby establishing an electrical connection. The response of the processing circuit 26 may result in a restriction of the functionality of the radio device 10. In particular, the response includes deleting data or content from the data memory 20 of the radio device 10.

[0046] An energy storage device 36 can be arranged in the housing 14 and is connected to at least one of the contacts 30, 32. In the illustrated example, the energy storage device 36 is connected to the second contact 32, with the first contact 30 being connected to the processing circuit 26.

[0047] The processing circuit 26 can be a passive circuit that is supplied with power when the first contact 30 and the second contact 32 come into contact with each other. This prevents current flow and thus energy consumption in the normal or initial state (i.e., when the housing 14 is closed), since the separating element 34 separates the two contacts 30, 32 from each other.

[0048] The second housing part 24 may include a fastening mechanism 38 for the separating element 34, via which the separating element 34 is fastened to the second housing part 24.

[0049] The fastening mechanism 38, as for example in Fig. 3, comprise a recess 40 in the second housing part 24, wherein one end of the separating element 34 is inserted, in particular glued, into the recess 40. Alternatively or additionally, the fastening mechanism 38 can have a clamping bracket that includes a spring to clamp the separating element 34 in place. A clamping part is thus spring-loaded to clamp the separating element 34.

[0050] Fig. 4 shows a schematic representation of the contact mechanism 28 of a radio device 10 according to the invention in a first embodiment, wherein the separating element 34 is located outside the contact area between the first contact 30 and the second contact 32.

[0051] In the example shown, an end portion of the first contact 30 has a curvature such that the end of the first contact 30 points away from the second contact 32. As can be seen, the separating element 34 can thus be pushed between the first contact 30 and the second contact 32 when the housing 14 is reclosed. More generally, an end portion of the first contact 30 and / or an end portion of the second contact 32 can have a curvature that is configured such that an end of the first contact 30 points away from the second contact 32 and / or an end of the second contact 32 points away from the first contact 30.

[0052] Fig. Figure 5 is a schematic representation of the contact mechanism 28 of a radio device 10 according to the invention in another embodiment. In the example shown, the separating element 34 is located outside the contact area between the first contact 30 and the second contact 32.

[0053] The end of the first contact 30 rests on the second contact 32. The separating element 34 is thus guided past the contact area between the first contact 30 and the second contact 32 when the housing 14 is reclosed. Alternatively, an end section of the second contact 32 can be designed such that the end of the second contact 32 rests on the surface of the first contact 30.

Claims

[1] Radio device with tamper protection, wherein the radio device (10) comprises a housing (14) in which a transmitter circuit (16) and / or a receiver circuit, a processing circuit (26) and a contact mechanism (28) for detecting a tampering attempt are provided, wherein the housing (14) comprises a first housing part (22) and a second housing part (24) which are movable relative to each other in order to move the housing (14) from a closed state to an open state, - wherein the contact mechanism (28) comprises a first contact (30), a second contact (32) and an electrically insulating separating element (34), wherein the separating element (34) is arranged in a contact area between the first contact (30) and the second contact (32) in the closed state of the housing (14) such that contact between the first contact (30) and the second contact (32) is prevented, - wherein the separating element (34) is connected to the second housing part (24) such that the separating element (34) can be removed from the contact area between the first contact (30) and the second contact (32) when the second housing part (24) is moved relative to the first housing part (22), thereby bringing the first contact (30) and the second contact (32) into contact with each other, and - wherein the processing circuit (26) is connected to the contact mechanism (28) and is configured to perform a response when the first contact (30) and the second contact (32) come into contact with each other. [2] Radio device according to claim 1, wherein the response of the processing circuit (26) results in a restriction of the functionality of the radio device (10), in particular comprising the deletion of data from a data storage device (20) of the radio device (10). [3] Radio device according to claim 1 or 2, wherein an energy storage device (36) is arranged in the housing (14) which is connected to at least one of the contacts, and wherein the processing circuit (26) is a passive circuit which is supplied with energy when the first contact (30) and the second contact (32) come into contact with each other. [4] Radio device according to one of the preceding claims, wherein the radio device (10) comprises a cryptographic circuit (18) for encrypting and / or decrypting information, which is arranged in the housing (14). [5] Radio device according to any of the preceding claims, wherein the radio device (10) is a handheld radio device. [6] Radio device according to one of the preceding claims, wherein the second housing part (24) is a closure cover of the radio device (10). [7] Radio device according to one of the preceding claims, wherein the second housing part (24) comprises a fastening mechanism (38) for the separating element (34) by means of which the separating element (34) is attached to the second housing part (24). [8] Radio device according to claim 7, wherein the fastening mechanism (38) comprises a recess (40) in the second housing part (24), wherein one end of the separating element (34) is inserted in the recess (40), in particular glued in place, and / or wherein the fastening mechanism (38) has a clamping holder comprising a spring to hold the separating element (34) in a clamping position. [9] Radio device according to one of the preceding claims, wherein an end section of the first contact (30) and / or an end section of the second contact (32) has a curvature such that a respective end of the first and / or second contact points away from the other contact. [10] Radio device according to one of the preceding claims, wherein at least the first contact (30) and / or the second contact (32) are mechanically preloaded, such that the first contact (30) and the second contact (32) come into mechanical contact with each other when the separating element (34) has been removed from the contact area between the first contact (30) and the second contact (32).

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