RU2596935C2 - Device for blocking unauthorised information tapping from cellular telephone - Google Patents

Abstract

FIELD: information security.

SUBSTANCE: invention relates to means of providing, in particular, to a device for blocking unauthorised information tapping from a cellular telephone, and can be used in mobile communication devices for personal use. Device for blocking unauthorised information tapping from a cellular telephone, placed in a case, comprises an electronic unit for blocking telephone. Electronic unit for blocking telephone consists of magnetically sensitive current switch and a permanent magnet. Magnetically sensitive current switch is installed inside housing of telephone and is connected to break of one of supply or signal buses of its assemblies to allow their disconnection, and permanent magnet is placed on wall of said case.

EFFECT: higher efficiency of protection.

5 cl, 2 dwg

Description

A device for blocking unauthorized removal of information from a cell phone is a means of ensuring information security and can be used in mobile communication devices for individual use.

It is known that turning off any cell phone using the standard off / on key does not exclude unauthorized remote turning on the phone and listening to voice information. To eliminate this possibility, electronic blocking nodes are used, which are radio wave suppressors of the communication channels of the telephone and the base cellular station (www.specagent.ru/index.php / ... о ... / glushilka-eto-vasha-bezopasnost, WO 98/18232 A1, H04K 3/00, 12/23/2013). The disadvantages of such suppression equipment are the noticeable weight and size characteristics of stationary devices, the dependence of operation on additional (with respect to the protected telephone) batteries (extra weight) or mains supply, as well as a possible unwanted radio wave effect on electronic devices operating in the area of the suppressor and not related to protected phone.

The closest analogue (prototype) in the prior art can be considered the blocker of the mobile cell phone - product "ASSISTANT" (www.aurix.ru/goods/goods9-7.html, 12/23/2013). As follows from the product description, the ASSISTENT electronic device blocking unit, after switching on, works almost continuously, blocking the microphone of the telephone (several telephones with their appropriate placement) if the microphone is near the acoustic noise emitter of the product. The ASSISTENT electronic blocking unit consists of a radio receiver tuned to the frequency of operation of the guarded telephone and an acoustic noise generator. All components of the electronic blocking unit are located inside the case (case, container) for storing a cell phone. In case of unauthorized switching on of the guarded telephone, the receiver of the “ASSISTENT” product registers the radio emission of the telephone and includes a noise blocker (acoustic noise generator), completely noisy microphone of the guarded cellphone.

The disadvantages of the device include the possibility of inoperability of the blocking device itself, for example, when its battery power is low. The product has dimensions of 115-75-24 mm, and it must be worn simultaneously with a cell phone, which significantly increases the overall weight and size characteristics of the device. There is also an increase in acoustic noise in nearby third-party telephone channels. In addition, the rapid development of electronic information processing, which makes it possible to isolate a useful signal against a background of noise and interference, does not exclude the emergence of algorithms that neutralize acoustic or electromagnetic noise created by such blockers.

The technical result of the invention is to increase the effectiveness of protection, by ensuring, if necessary, a complete disruption of the cell phone without the need for physical removal of components or blocks from it, such as a battery. Obviously, the physical removal of the battery from the phone’s case dramatically solves the problem of effectively protecting this phone from unauthorized switching it on.

The specified technical result is achieved by the fact that a magnetically sensitive current key is built in to the gap of one of the telephone supply or signal buses, the gap of which allows guaranteed shutdown of the most important nodes or blocks of its circuit and thereby eliminating the possibility of unauthorized switching on the phone. A permanent magnet is fixed on the wall of the case (container, case), which allows to disconnect the indicated nodes with its magnetic field, with the appropriate location in the phone case.

The essence of the proposed technical solution lies in the fact that there are several vulnerabilities in the telephone circuitry, the galvanic rupture of electrical contacts in which to one degree or another excludes the phone’s ability to turn on or transmit acoustic signals in practice. Such vulnerabilities include, for example, microphone switch-on buses, power amplifier cables for the radio signal, communication wires for the radio signal amplifier and antennas, battery buses for the entire electronic circuit of the telephone, conductors for connecting the SIM card to the telephone electronic circuit.

In one of these places, in the gap of the conductor (bus), a magnetically sensitive current switch can be installed, the internal electrical resistance of which depends on the presence or absence of a control magnetic field of the required strength. In the presence of the indicated magnetic field, the magnetically sensitive key has a high value of electrical resistance (ideally equal to infinity). This corresponds to the breaking state of the selected conductor (bus). In the absence of a control magnetic field, the key is closed, its resistance is close to zero, the conductor selected for switching is almost galvanically closed and ensures the normal operation of a cell phone. The source of the control magnetic field (permanent magnet) is fixed inside (outside) on / on the wall of the cover (container, case) for carrying a cell phone. The size and strength of the field strength of the specified magnet, as well as the place of its fastening in the case, are selected such that, with the phone inserted in the case, the magnet's effect on the magnetically sensitive current key located in the cell phone is maximum, and at the other position, it is minimal.

Modern microelectronic technologies make it possible to produce a magnetically sensitive current switch in micro-sizes and with micro-consumption of electric energy (ideally, with zero power consumption).

In addition, the magnetically sensitive current key itself can be placed on the circuit board or on the fastener elements inside the phone case with an offset closer to one of the faces of this case.

The invention is illustrated by drawings, where in FIG. Figures 1 and 2 show one of the possible variants of a device for blocking unauthorized information retrieval installed in a cell phone for the purpose of switching the electrical connection of one of the poles of the telephone battery and its electronic circuit.

The device for blocking unauthorized removal of information from a cell phone is an electronic blocking unit, consisting of two parts. The first part of the electronic locking unit is shown in FIG. 1. It contains: a housing 1 of a cellular telephone, shown on the side of the removed cover (not shown), which consists of a circuit board with electronic circuit 2 and a battery 3. The pole 4 of the battery 3 is common, galvanically connected to the corresponding bus of the electronic circuit 2. The second pole 5 of the battery 3 is galvanically isolated from the second power bus 6 of the electronic circuit 2. A magnetically sensitive current switch 7 (hereinafter the current switch), for example a reed switch with normally closed contacts, is mounted on the fastener elements of the battery 3 near the end 8 and side wall 9 of the housing 1. An electric wire 10 galvanically connects the contact 12 of the current switch 7 (reed switch) to the second pole 5 of the battery 3. An electric wire 11 galvanically connects the contact 13 of the current switch 7 to the second power rail 6 of the electronic circuit 2.

In FIG. 2 shows the second part of the electronic blocking unit, it is a cover 14 (case, container) with a permanent magnet 15 mounted on its wall.

The operation of the device blocking unauthorized removal of information from a cell phone, such as voice, is as follows. Under normal conditions, when there is no need for a guaranteed disconnection of the cellular telephone 1 from the ether, it (in a closed state) is placed in the case 14 in such a way that the electronic circuit 2 of the telephone in which there is no magnetically sensitive current key 7 is located in the coverage area of the permanent magnet 15 Therefore, the phone operates in its normal mode, because the current switch 7 is outside the range of the permanent magnet 15 and is in a closed state, and the pole 5 of the battery 3 and the power bus 6 are galvanically shorted. Placing the telephone 1 in the case 14 in a position in which the magnetically sensitive current switch 7 falls within the control magnetic field of the permanent magnet 15 leads to the opening of the current switch 7 and rupture of the switched poles 5 of the battery 3 and the power bus 6 of the electronic circuit 2. This leads to galvanic disconnection of the electronic circuit 2 from its battery 3.

In addition to the radio channel for communication with the base station (hundredth), modern cell phones use short-range wireless radio interfaces, such as Bluetooth, WiFi, etc., which, in principle, allow unauthorized removal of information from a cell phone. Using such radio interfaces, it is also possible to unauthorizedly introduce telephone viruses or trojans into the telephone, with the subsequent destruction or dumping of the information stored in the telephone.

The proposed technical solution allows simultaneously with the blocking of the cellular radio channel to exclude the possibility of unauthorized connection to the phone through its wireless radio interfaces.

Claims (5)

1. A device for blocking the unauthorized removal of information from a cell phone placed in a case, containing an electronic telephone blocking unit, characterized in that the electronic blocking telephone unit consists of a magnetically sensitive current key and a permanent magnet, while a magnetically sensitive current key is installed inside the phone and is turned on into the gap of one of the supply or signal buses of its nodes to ensure their shutdown, and a permanent magnet is placed on the wall of the said cover. 2. The device according to p. 1, characterized in that the magnetically sensitive current key is configured to be installed at one of the ends of the cell phone housing. 3. The device according to p. 1, characterized in that the permanent magnet is placed opposite the magnetically sensitive current key with the most effective impact on the magnetically sensitive current key. 4. The device according to claim 1, characterized in that the magnetically sensitive current switch is made in the form of a reed switch. 5. The device according to claim 1, characterized in that the magnetically sensitive current switch is made using microelectronic technology.

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