FR3014618A1 - METHOD AND INTERFERENCE DEVICE WITH CONFINED LINEAR EFFECT - Google Patents

Abstract

Apparatus and method of confined interference disposed in a coverage area in which there may be prohibited radio communication devices whose operation is sought to prevent, characterized in that it comprises at least the following elements: • at least one linear element ( 1) comprising a plurality of orifices Oi allowing the radiation of jamming signals, the linear overhead being connected to one or more effectors via a connector (3), • the one or more effectors (2) generating, being adapted to inject at one end at least one of the linear overhead (1) one or more interference signals, the power flow Pj, f of the jamming signal Jj, f in the band Bj, f of a carrier f is chosen such that the PS ratio, j, f / PJ, f, between the power flow PS, j, f of the signal Sj, f potentially usable by the forbidden device on the carrier f and the power flow PJ, f, of the signal Jf present on the carrier fp To prevent the forbidden device from operating is below the Threshold operating threshold, j, f of the forbidden device.

Description

The invention relates to a method and a scrambling device using an overhead line and a scrambling device, the assembly being adapted to generate and broadcast disturbing or jamming signals in a closed space or semi-open given without impact on the operation of the elements arranged outside this space. It finds its application to disrupt or prevent the operation of radio systems, radiocommunication devices, the use of which is unlawful, or radio systems that do not have operating authorization, in enclosures, prisons, cinemas examination, etc. In certain environments such as prisons, examination centers, schools, some embassy halls, experimental centers, etc., the use of radio devices, such as mobile phones, is prohibited. One of the problems today is to eradicate all unauthorized radiocommunications in a closed enclosure by controlling the containment of the signal used to prevent such communications by avoiding any inconvenience to outside users not concerned by this prohibition of radiocommunications. The state of the art known to the applicant describes detection systems and jamming systems that will block the illicit radio communications and the systems that use them from conventional radio antennas. These devices have many disadvantages; because of geometric losses in 20.1ogio (R) of the power radiated from a conventional antenna (R being the distance to the phase center of the antenna), they are poorly suited in terms of efficiency, coverage, power output ; the containment is not satisfactory, which generates complaints from operators and external users not affected by this prohibition; they are very delicate to install and maintain, and often expensive as soon as significant coverage has to be obtained. There is at present a need for a device allowing complete jamming of radio communications deemed to be illegal, a device that applies within a given closed space in general (or known as "space" indoor "), whose effectiveness is reliable, controlled coverage, confined effect, and controlled containment. The term "unlawful or prohibited terminal" means a terminal, a radiocommunication device that is not authorized to operate in a given area and outside that perimeter. We shall use indifferently the expression "linear element" or "linear air" to designate the same element.

The object of the invention is based in particular on the use of one or more linear geometry airplanes associated with effectors consisting of suitable scrambling devices and couplings. The use of these effectors and the linear geometry of the aerial allow both: - to ensure a reliable coverage of the interference, - to control the confinement of the interference, - to simultaneously transmit many jamming signals simultaneously addressing a large number of frequency intervals and a large number of radiocommunication systems whose frequency plans are included in these intervals.

The invention relates to a confined interference device disposed in a coverage area in which there may be prohibited radio communication devices whose operation is sought to prevent, characterized in that it comprises at least the following elements: - at least one linear overhead device comprising a plurality of orifices Oi allowing the radiation of jamming signals, the linear overhead being connected to one or more effectors via a connector, - the one or more generating effect elements being adapted to inject at at least one end of the aerial one or more scrambling signals, the power flow Pi, f of the jamming signal Ji, f in the band Eii, f of a carrier f is chosen such that the ratio Psj, f / PJ, f, between the stream power Pse of the signal Si, f potentially usable by the forbidden device on the carrier f and the power flow PJ, f, of the signal Jf present on the carrier f to prevent the device prohibited from operating is less than the operating threshold Thresholds, i, f of the forbidden device (Ps, i, f / PJ, f According to one variant embodiment, the effector is adapted to generate, for a point M (r, I) where is a forbidden radiocommunication device, a value of the spectral density Ni, f (r, l) of the interference signal injected into the overhead line via the connector such as for the Bif band of each carrier f 10.1ogio (Ni, f (r, 1) .13i, f) k10.1ogio (Ps, i, f) -10.1ogio (Thresholds, i, f) + C (ro) -F P '. (1-10) + 10.1og1o (r / r0) -Fri where. r, I, are the coordinates of a point M,. lo designates a linear distance of reference, ro denotes a reference radial distance to the linear element,. P 'denotes the rate of the linear losses along the aerial radiating from the distance lo,. -C (ro) denotes the losses by coupling in the band 13, j at the reference radial distance ro, rt represents a margin of caution taking into account the additional attenuations of the jamming signal during its propagation from the air to the forbidden terminal.

The effector is, for example, adapted to generate transmission power taking into account one or more of the following elements: measurements of the levels of the beacon, control and traffic signals coming from transmitters present in the external networks liable to enter into communication with illicit devices, - the rate P 'of linear losses in linear overhead, - the losses by coupling C (ro) of linear overhead, - margins ri intended to to compensate for additional attenuation of various types which may affect the jamming signal J during its propagation from the linear overhead to the device to be scrambled. According to one variant, the characteristics of the prohibited radiocommunication devices and the characteristics of the aerial radiation regime are previously known or measured in order to parameterize and adjust the frequency bands of the interference signal, the nature of the jamming signals emitted and the levels at the output of the effector whose signal is injected into the air via the coupler.

At least one of the effectors is, for example, suitable for generating and transmitting the scrambling signals and is a generic broadband scrambler. The effector is, for example, adapted to the generation and the emission of jamming signals is composed of a set of dedicated jammers, the output signals of which are transmitted to filter and amplification and rectification modules, then injected into a coupler, the output of said coupler being injected into the linear aerial. According to one variant, the effector is, for example, adapted to the generation and transmission of the interference signals, comprises frequency-selective filtering modules adapted to excise the jamming signal in order to release one or more carriers that can be used by an over-network. controlled radiocommunications. The device may comprise means adapted to duplex the signal at the output of an effector and a device for injecting said signal into two different linear aerials.

The device may also comprise a first effector disposed at a first end of the linear overhead and a second effector disposed at a second end of the linear overhead line in order to inject a jamming signal J1, J2 at each end of the linear air.

The device may include a system of baffles adapted to locally optimize the confinement, baffles for which one can use grilles for passage of electric cables with inverted mounting, mesh meshes and various geometries. The invention also relates to a method of jamming the operation of one or more radiocommunications devices prohibited in a given area, implemented in the device having one of the preceding characteristics, the method is characterized in that it comprises at least the following steps: - use at least one linear overhead comprising several orifices Oi allowing the radiation of jamming signals, the linear overhead being connected to one or more effectors via a connector, - injecting at least one end of the one or more scrambling signals, the power flow Pi, f of the interference signal Ji, f in the band 13j, f of a carrier f is chosen such that the ratio Ps, j, f / PJ, f between the power flow Pse of the signal Si, f potentially usable by the forbidden device on the carrier f and the power flow PJ, f, of the signal Jf present on the carrier f to prevent the dispo It is forbidden to operate below the operating threshold Thresholds j j of the forbidden device (Ps, i, f / Pj, f Seils, j, f).

For the implementation of the method, a value of the spectral density Ni, f (r, l) is generated for the interference signal injected into the linear antenna such as for the Bif band of each carrier f 10.1og1o (Ni, f (r, 1) .131, f) k1 0.1og1o (Ps, i, f) -10.1ogio (Thresholds, i, f) + C (ro) + P '. (1-10) + 10.1ogio (r / 1) r0) + ri where. r, I, are the coordinates of a point M,. lo denotes a reference linear distance,. ro denotes a reference radial distance to the linear element,. P 'denotes the rate of the linear losses along the aerial radiating from the distance lo, -C (ro) denotes the losses by coupling in the band Bj at the reference radial distance ro, ri represents a margin of precaution taking into account the additional attenuation of the jamming signal during its propagation from the air to the forbidden terminal. Other characteristics and advantages of the method and of the device according to the invention will appear better on reading the following description of an exemplary embodiment given by way of illustration and in no way limiting attached to the figures which represent: FIG. example of a device according to the invention comprising a linear element at the input of which a scrambling device injects a scrambling signal dedicated to the eradication of unauthorized radiocommunications, FIG. 2 a detail of linear element, FIG. an example of an arrangement of a linear element provided at each of its ends with an effector and implemented in a space with a preferred direction; - FIG. 3b, a possible example of arrangement of several linear elements for the implementation of the method in a closed space of rectangular or square shape whose linear elements define the perimeter, in which the s The interference signal, emanating from two effectors present at the ends of a diagonal, is distributed in each half-perimeter, FIG. 4, a representation of a linear element with an effector connected to each end. In order to better understand the subject of the invention, the description is given for illustrative and not limiting purposes for an application intended to prevent the operation (transmission / reception) of a mobile phone whose use is prohibited within of a prison, that is to say that we will ensure that the signaling signals to this mobile phone can not be decoded or interpreted by the latter, which makes it impossible for any access to the network any request for a call or any answer to the calls. This example can be extended to all radio devices whose operation is not allowed in a given space. FIG. 1 schematizes a first exemplary embodiment of the device according to the invention comprising an overhead with linear geometry 1, associated with a device for generating disturbing waves or effector 2, via a connector 3. The mobile telephone 4 which is not Not allowed to receive communications or data is found on this figure in the vicinity and in the efficiency zone of the linear overhead. The effector 2 is for example composed of: - one or more devices for generating and transmitting interference signals 5, 5 ', - one or more filtering modules and amplification and rectifying stages 6, 6', signals emitted by the above-mentioned generation and transmission devices, these filtering and amplification modules making it possible to finely adjust the bands, the carriers and the output levels, of a coupler 7 making it possible to constitute the signal actually injected into the 1 Such an arrangement makes it possible to produce a broadband interference signal or a multi-band interference signal, frequency bands, carriers and adequate levels in given areas where mobile telephones are used. which one seeks to prevent the operation can be found. In practice, the scrambling signal is injected into the linear overhead via the connector 3 with a level adjusted on each band and on each carrier in these bands to scramble and prevent on these carriers all data exchange between the mobile terminal and prohibited communications networks throughout the area covered by linear overhead. That is to say that in the example of FIG. 1, the resulting jamming signal J, considered at the forbidden terminal, has, for each of the carriers potentially usable by the forbidden terminal, a power Pj defined as a function of the power Ps of the signals heard by the forbidden terminal, so that the ratio Ps / Pj is less than the operating threshold Thresholds of the prohibited mobile phone on each usable carrier (this operating threshold Thresholds being known to those skilled in the art for each radio network to be banned by consulting the standards of these networks). The aerial linear geometry 1 has for example radiation characteristics which, combined with suitable effectors as described above, can disrupt the operation of mobile phone present at the point M (r, l) by precisely controlling the flow the radiated power Pj (r, l) as a function of the linear distance I and the radial distance r which define the positions M (, I) of one or more illicit devices (ie the positions of the mobile telephones 4 in the area covered by linear overhead). The linear distance I is defined, for example, with respect to the connector 3 of the linear element. The radial distance r is determined by the measurement of the perpendicular to the linear element which meets the point M (r, l), for example. More precisely, the radiated interference power flow Pj (1, r) by the aerial in a scrambled band Bj at the point M (r, l) indicated by the linear distance I and the radial distance r, is given in decibel ( dB) by the "cylindrical" radiation regime expressed by the following formula: 10.1ogio (Pj (I, r)) = 10.1ogio (P0 (10)) - C (ro) - P '(I-10) - 10.1ogio (r / ro) (1) .1describing the linear distance,. where r denotes the radial distance to the linear element, where lo designates a linear distance of reference (generally one skilled in the art considers lo as zero or very weak and corresponds for example to the output of the coupler 7) and P0 (10) designating the corresponding power in the band Bj resulting from the injection of the interference signal into the air via the connector 3,. P 'designating the rate of linear losses along the aerial radiating from the reference linear distance Io (assumed loss, to simplify the writing but without limitation of generality, constant in the band Bj, itself assumed sufficiently narrow); this value is a manufacturer datum in general or a quantity paired by the measurement in each of the bands Bj, this value is at most a few dB per 100 m of propagation in the air,. where ro denotes a reference radial distance to the linear element (generally one skilled in the art considers ro = 2 m), 15. -C (ro) designating the coupling losses in the band Bj at the reference radial distance ro; (-C (ro), constructor data in general, or paired by measurement, has a value of the order of -55 dB at -70 dB at a radial distance of reference ro = 2 m, homogeneous over the length of the aerial) . . Pj (I, r) is the power flow in the band Bj of the signal J at the point M (r, I). In the case where there are several interference signals, the power Pj considered is global and can correspond to several sub-bands (in this case what counts for the interference efficiency is Ps / Pj <Thresholds in the band previously noted Bj of the carrier of S). In the formulation (1) above: 25. the rate of linear losses P 'by propagation in the air is low, which guarantees a uniform level of aerial radiation over the lengths targeted by the invention, the linear distance typically satisfying the [10,11; L 100 m,. the cylindrical regime (expressed in dB by -10.1ogio (r / r0) in the formulation (1)) of radiation propagation losses is linearly dependent on the inverse of the radial distance r at the linear air and not quadratically the inverse of the distance R (actual distance / phase center) absolute at the center of phase of the air as in the case of conventional systems described in the state of the art. The dimensions of the linear air element, its diameter 1), its length L and its orientation with respect to the geometry of the zone to be covered, as well as the distribution of the orifices Oi allowing the diffusion of the jamming signals J and the positioning of the Possible baffles to facilitate the confinement are chosen in particular according to the radiocommunication devices whose operation it is desired to eradicate, and the geometry of the zone in which it is desired to eradicate the operation of illicit radiocommunications. When the area to be covered has privileged directions (corridors, corridors) as in FIG. 3a, the orientation of the linear elements is carried out, for example, tangentially to these privileged directions. When the area to be covered is a closed enclosure without privileged direction, as in Figure 3b, the aerials are arranged for example tangentially to the edges of this enclosure. The emission powers of the effector 2 are adjusted, for example by taking into account one or more of the following elements: the measurements of the corresponding field levels coming from the transmitters 8, 9, 10, 11 present in the external networks and likely to communicate with the illicit terminals whose radiocommunications are to be eradicated, and - the loss regime explained by formula (1) above, and - margins designed to compensate for additional attenuations of various kinds. which can affect the jamming signal J during its propagation from linear airborne 1 to the transmitting device to be scrambled, 4 (walls, doors, human body, etc.). The objective is to obtain an interference signal J of at least one level such that, in each band Bi j = 1 ... J and for each beacon or control channel f in each band Bi corresponding to the external transmitters likely to communicating with the illicit transmitter / receiver terminals whose radiocommunications are to be eradicated, the power flow Pi, f of the interference signal Ji, f in the band Bif of the carrier f is such that the signal Si, f potentially usable by the forbidden terminal (index i) on the carrier f, of power flow Psnif, is received with a ratio Ps, i, f / Pij less than the operating threshold Thresholds, i, f of the forbidden portable terminal (this operating threshold Thresholds , i, f being known to those skilled in the art for each radio network and for each type of carrier beacons f to prohibit, by consulting the standards of these networks). Or again, the ratio Psi, f / PJ, f, between the power flow Pse of the signal Si, f potentially usable by the forbidden device on the carrier f and the power flow PJ, f, of the signal Jf present on the carrier f to prevent the forbidden device from operating is below the operating threshold Thresholds, i, f of the forbidden device (Psi, f / PJ, f Thresholds, i, f). This is written in decibels: 10.1ogio (Psj, f) - 10.1ogio (Pi, f) 10.1og1o (Thresholds, i, f) in the B band; , f of the carrier j, f, j being the index of the band of the terminal, that of the carrier, or else 10.1og1o (Pi, f) 10.1og1c (Ps, i, f) - 10.1ogio (Seuilsv) in band B; F Considering a terminal forbidden at the point M (r, l), the spectral density Ni, f (r, l) of the interference signal injected into the linear overhead via the connector 3 must therefore verify for the band Bj , f of each carrier f 10.1ogio (Nij (r, 1) .Bi, f) -C (r0) -P '. (1-10) -10.1ogio (r / r0) k10.1ogio (Psd, f) -10. 1ogio (Thresholds, i, f) -Fi is again: 1 0.1ogio (Ni, f (r, 1) .13u) kl 0.1ogies, i, f) -1 0.1ogio (Thresholds, i, f) + C ( ro) + P '. (140) + 10.1ogio (dro) -Fi (2) where r1 represents a certain margin of precaution to take into account additional attenuations of the interference signal during its propagation from the air to the forbidden terminal 4 This condition expressed in formula (2), to be satisfied for an area defined by a radius r05r5 rmax, 10 <l <Lmax a sufficient condition is to check for r = rmax, 1 = 1-max, 11 = r1max 10.1ogio (Nif.Bi, f) k10.1ogio (Ps, i, f) -10.1ogio (Thresholds, i, f) + C (ro) + P'- (1-max-10) + 10.1ogio (rmax / ro) -FrImax (3). The illustrative and nonlimiting example of FIG. 1 shows radiocommunication signals Sg, S9, S10, S11 originating from external transmitters 8, 9, 10, 11 in bands B8, B9, B10, B11, the transmitters being capable of enter into communication with the illicit terminal 4 whose radiocommunications are to be eradicated. For this configuration, if we consider a beacon carrier or control by external transmitter, at carrier frequencies respectively denoted f8, f9, f10, wire, and bands respectively denoted BJ, g, BJ, 9, BJ, 10, BJ , 11, if we note Ps, 8 PS, 9 PS, 10 PS, 11 the corresponding power flows received by the illegal terminal 4, if we note Thresholds, 8 Thresholds, 9 Thresholds: 10 Thresholds, ii points of operations (known to those skilled in the art) of the illicit terminal 4 in the bands B, j, 8, BJ, 9, BJ, 10, BJ, ii of the carriers f8, f9, f10, f11, the signal levels of minimum interference PJ, 8 PJ, 9 PJ, 10 PJ, 11 to be received by the illegal terminal 4 in bands Bj, g, Bj, 9, Bj, 10, Bj, 11 satisfy the following conditions In real quantities: Ps , 8 / Pj, g Thresholds, 8 in the band BJ, 8 of the carrier f8 Ps, 9 PJ, 9 Thresholds, 9 in the band Bj, g of the carrier f9 Pslo PJ, 10 <SeUilg, 10in the band BJ, 10 of the carrier f10 / Pj, i1 <thresholds, ii in the band BJ, 11 of the carrier f11 In decibels: 10.1ogio (PJ, 8)> _ 10.log1o (Ps, 8) -10.1og1o (Thresholds, 8) in the band B, J, 8 of the carrier f8 10.1ogiO (PJ, 9)? 1 0.10 gleg, 9) -10.1ogio (Thresholds, 9) in the band BJ, 9 of the carrier fg 10.1ogio (PJ, 10) 10.1ogio (Pslo) -10.I0g1o (Thresholds, 10) in the band BJ, 10 of the carrier f10 1 0.1ogio (PJ1) -k1 0.1ogio (Ps, ii) -1 0.1ogio (Thresholds, i 1) in the band B, j, 11 of the carrier f11 and this, on the zone covered by the linear air. It is deduced that the spectral power density levels injected N8.8 Ns, 9 NS, 10 Ns, 11 in the linear overhead via the connector 3 must verify the following conditions in decibels: 1 0.1ogio (Nm i (r, 1) .B4O1) k 1 0.1ogies, i) -10.1ogio (Thresholds1) + C (ro) + Fv. (I-Io) + 10.1ogio (r / r0) + Tiii 1 0.1ogio (N1J10 (r, 1 ) .BJ, 10) k 1 0.1ogies, 10) -1 0.1ogio (Thresholds, 10) + C (ro) + PA-10) + 10.1ogio (r / r0) + 11lo I 0.1ogio (1 \ 1J, 9 (r, 1) .BJ, 9) k 1 0.1ogies, 9) -1 0.1ogio (Thresholds, 9) + C (ro) -FP '. (1-1o) +1 0.10g (riro) + TI9 1 0.1ogio (N1J, 8 (r, 1) .BJ, 8) k 1 0.1ogio (Ps, 8) -1 0.1ogio (Thresholds, 8) + C (ro) + P (1-10) +1 0.1ogi 0 (r / 0-Fia 119 X10 Till represent certain precautionary margins to take into account additional attenuations of the jamming signal during its propagation from the aerial to the forbidden terminal 4 in the bands B8, B9, B10, B11 The effector device 2 for generating and transmitting the scrambling signals is composed of, for example, a generic broadband scrambler. u well of a set of jammers each dedicated to one of the radiocommunications networks prohibited in the covered area, amplitude-adjusted where appropriate, and whose outputs are coupled according to methods well known to those skilled in the art before injection in the overhead line so as to process multiple Bi bands and multiple carriers simultaneously. Its characteristics are for example chosen according to the illicit devices likely to be in a supervised area. This allows somehow to build an effector "à la carte" specifically adapted to the processed radio configuration and networks whose communications must be locally neutralized. For example, it is possible to use dedicated third and fourth generation radio-cellular jammers, GPS (Global Positioning System) jammers operating the industrial ISM band (Industrial, Scientific and Medical). ) (Bluetooth short radio type, or following WiFi wireless protocol), etc. (see Figure 1, 5 and 5 '). These dedicated jammers have low power / per subband (<1 W), low cost (odg 100 $ unit x qq units per device). It is also possible to use an additional device adapted to straighten power levels by amplification and dedicated filtering of each subband to compensate if necessary a frequency dispersion of the necessary emission levels (see Figure 1) and in particular: - an inhomogeneity of cable losses as a function of frequencies (dispersive linear airspeeds) - an inhomogeneity of the signal levels S8, S9, S10, S11 received by the illicit radio systems and which one wants to scramble. According to another variant embodiment, frequency excision, a method known to those skilled in the art, of one or more carriers in the scrambling signal by a filtering adapted at the level of the amplification and rectification stages (6, 6 '), so as to allow the use of these carriers for radio controlled by the system operator, emergency calls, authorized on-network radiocommunications, etc. The method according to the invention associated with the example of FIG. 1 comprises, for example, the following steps: 1) defining the arrangement of the linear aerials in a zone to be controlled in which the illicit radiocommunications must be prevented, 2) defining parameters for an interference signal: frequency band, interference power flux levels in the area to be controlled, expressed as a function, in particular, of the radial distances of the various points of the zone at the linear airspaces arranged to cover said zone, of field level measurements or of the aforementioned elements, 3) emit a power signal adapted to scramble the illicit devices present in the controlled zone from the linear aerials which are arranged therein, the signal level being such that the ratio between the operating power flow of the device unlawful and the interference signal power flow is less than the threshold value of operation of the illicit device. Figure 2 is a detail of an example of a linear cable comprising a plurality of orifices arranged to allow the passage of interference waves in the area to be monitored. The linear air comprises several orifices Oi distributed along the element according to the desired application, the orifices are separated by sections 21 which do not allow the passage of jamming signals. FIG. 3a schematizes an alternative embodiment of the invention in a corridor-type preferred direction enclosure in which a single element 301 has been installed at a ceiling and two effectors 305 306 at the opposite ends of the ceiling. element, as described above. The orifices of the linear element allow the emission of interference signals J1, J2, the mobile phone 4 located in the corridor can not decode the signals emitted by exteriors. The interference parameters, power level, will be selected in particular according to the linear arrangement of these linear elements. FIG. 3b schematizes an alternative embodiment of the invention in an enclosure having no privileged direction, in which four linear elements 311, 312, 313, 314, of length L2, L1, L2, L1 respectively, have been installed, at the unrepresented walls of a piece of square geometry to monitor and two effectors 315, 316 at opposite ends of one of the diagonals of the room, as described above. The effector 315 is connected according to an arrangement described in FIG. 1 to the two linear elements 311, 312, the effector 316 is in connection with the linear elements 313, 314. The orifices of the four linear elements allow the emission of jamming J1, J2, J3, J4, the mobile phone 4 located in the room can not decode the signals emitted by exteriors. The scrambling parameters, the power level, will be selected in particular according to the square arrangement of these linear elements.

FIG. 4 represents another embodiment, it will be possible to connect a first effector 42a at a first end 41a of the linear aerial 41 via a first connector 43a and a second effector 42b at the second end 41b of the aerial linear 41 via a second connector 43b to inject a scrambling signal J1, J2 at each end of the linear overhead 41. In this case, the first and second effector have substantially identical characteristics (same levels). transmission, same frequency bands), but their signals are decorrelated according to a technique known to those skilled in the art in order to avoid the phenomena of interference and standing waves during their propagation in the linear air of the linear air This embodiment makes it possible in particular: to better homogenize the level of the jamming signal J in linear aerials by means of a two-way propagation , and to guarantee a better coverage of the interference, - to reduce the emission levels of the jamming signal at the ends of the overhead line and thus to guarantee a better confinement of the interference Without departing from the scope of the invention of other variants of implementation of the invention are possible.

For example, it is possible to add baffles to the device to locally optimize the confinement. For the nature, the shape and the size of the baffles, it is possible to use: grids for the passage of electric cables (frequencies> 900 MHz) with inverted mounting, grids of meshes and various geometries. The example of an open rectangular grid aperture> _ (A12) 2 (At: wavelength of the interference emission) leads to a directivity of about 120 °, a forward / backward ratio of the order from 10 to 15 dB).

This facilitates the confinement of the jamming signal during installation in "semi-open environment", for example for windows prisons or window examination / conference rooms, or when there are diffraction problems (metal pipes, other).

Another variant is to add a metrology in phase installation / maintenance which facilitates the installation and adjustment of the device. For this purpose, it is possible to use a spectrum analyzer, or else mobile spectrum control stations known to those skilled in the art. According to another variant embodiment, it is possible to add a totally controlled "over-network" of wired communications, or else a "on-network" of communication using line currents, etc. According to another variant embodiment, it is possible to add a totally controlled "on-board" radio-communication "over-network", by means of the following elements: - choice of carrier frequencies according to a preliminary survey of the frequency schedules of the external networks according to methods known to those skilled in the art. - if necessary, frequency excision of the jamming signal to "release" the carriers and make them exploitable. - installation of a local area network microphone using the released carriers and relay to external network. Examples of components usable on the carriers released for such an on-network are wireless access points DECT (Digital Enhanced Cordless Telephone), pico / femto-cells of the third generation system UMTS (Universal Mobile Telecommunications System) or of the LTE (Long Term Evolution) standard, Wi-Fi or WiFi Direct points, UMTS "device-to-device" terminals or LTE manet (Release 12) terminals known to those skilled in the art, etc.

The device and the method according to the invention have the following advantages in particular: - a total eradication of radiocommunications in the range 0.3 3 GHZ, with a single device according to the invention, - a jamming confinement to a given area without impact on the external environment, because of the linear nature of the aerial and the consequent loss of cylindrical losses according to the formulation (1) - flexibility of installation, with deployment of "à la carte" devices, - ease of maintenance, - many possibilities of extension in terms of added functions and in terms of services.

Claims (12)

CLAIMS1 - Confined interference device disposed in a coverage area in which there may be prohibited radio communication devices 5 whose operation is sought to prevent operation, characterized in that it comprises at least the following elements: - at least one linear overhead (1) comprising a plurality of orifices Oi allowing the radiation of jamming signals, the linear overhead (1) being connected to one or more effectors (2) via a connector (3), - the one or more effectors (2) generating , being adapted to inject at least one of the overhead line (1) one or more interference signals, the power flow Pi, f of the interference signal Ji, f in the band Bi, f of a carrier f is chosen such that the ratio PS, j, f / PJ, f, between the power flow Pslf of the signal Si, f potentially usable by the forbidden device on the carrier f and the power flow PO, of the signal Jf present on the p To prevent the prohibited device from operating is less than the operating threshold threshold of the forbidden device (Ps, i, f / PJ, f 5 Seils, j, f). 20 2 - confined interference device according to claim 1 characterized in that the effector (2) is adapted to generate, for a point M (r, l) where is a prohibited radiocommunication device (4), a value of the spectral density Ni, f (r, l) of the interference signal injected into the linear overhead via the connector (3) such that for the band Bi, f of each carrier 10.1og10 (Ni, f (r, 1 ) .Bij) k oiogio (Ps34-10.logio (Only they, i, f) + C (ro) + P '. (I-10) + 10.1ogio (r / r0) + ri where r, I, are the coordinates of a point M, where lo denotes a reference linear distance, ro denotes a reference radial distance to the linear element, 30. P 'denotes the rate of linear losses along the aerial radiating from the distance lo ,. -C (ro) denotes the coupling losses in the band 13, j at the reference radial distance ro, TI represents a margin of caution taking into account the additional attenuations of the jamming signal during its spread from the air to the forbidden terminal. 3 - scrambling device according to one of claims 1 to 2 characterized in that said effector (2) is adapted to generate a transmission power taking into account one or more of the following: - the measurements of the levels of beacon, control and traffic signals from transmitters (8, 9, 10, 11) present in the external networks and capable of communicating with the illicit devices, - the rate P 'of linear losses in the linear, - Losses by coupling -C (ro) of the overhead line, - Margins ri intended to compensate for additional attenuations of various types which may affect the jamming signal J during its propagation from the overhead line ( 1) to the device (4) to be scrambled. 4 -A jamming device according to claim 1 wherein the characteristics of the prohibited radiocommunication devices and the characteristics of the radiation regime of the aerial are previously known or measured to set and adjust the frequency bands of the interference signal, the nature of interference signals emitted and the output levels of the effector whose signal is injected into the air via the coupler (3). 5 - jamming device according to one of the preceding claims characterized in that at least one of the effectors (2) is adapted to the generation and emission of jamming signals is a broadband generic scrambler. 6. Interference device according to one of the preceding claims, characterized in that the effector (2) adapted to the generation and transmission of jamming signals is composed of a set of dedicated jammers, whose output signals are transmitted to filtering and amplification and rectification modules (6, 6 '), then injected into a coupler (7), the output of said coupler (7) being injected into the linear aerial (1). 7- scrambling device according to one of the preceding claims characterized in that the effector (2) adapted to the generation and emission of interference signals comprises frequency selective filtering modules adapted to excise the interference signal for to release one or more carriers that can be used by a controlled radiocommunication over-network. 8- scrambling device according to one of the preceding claims characterized in that it comprises means adapted to duplex the signal output of an effector and a device for injecting said signal in two different linear air. 9- scrambling device according to one of the preceding claims characterized in that it comprises a first effector (42a) disposed at a first end (41a) of the aerial line (41) and a second effector (42b) disposed at a second end (41b) of the linear overhead to inject an interference signal-111 j2 at each end of the aerial tinéique (41). 10- scrambling device according to one of the preceding claims characterized in that it comprises a system of baffles adapted to locally optimize the confinement, such as grilles passage of electrical cables with inverted mounting, mesh meshes and geometries variety. 11 - Confined scrambling method of the operation of one or more radiocommunications devices prohibited in a given area, implemented in the device according to one of claims 1 to 10 characterized in that it comprises at least the following steps use at least one linear overhead device (1) comprising a plurality of orifices Oi allowing the radiation of jamming signals, the linear overhead being connected to one or more effectors (2) via a connector (3), - injecting at one end to less than the linear overhead (1) one or more interference signals, the power flow Pm of the jamming signal Jm in the band Bm of a carrier f is chosen such that the ratio Psjf / PJ, f, between the stream of power Pslf of the signal Sm potentially usable by the forbidden device on the carrier f and the power flow Pj, f, of the signal Jf present on the carrier f to prevent the prohibited device from operating is less than the threshold l Operation of the forbidden device (Ps, j, f / PJJ SeLlils, i, f). 12 - confined interference method according to claim 10 characterized in that it generates a value of the spectral density Nm (r, l) for the scrambling signal injected into the linear air such that for the band Bj.f of each carrier f 10.1ogio (Nm (r, I) .Bi, f) 10.1ogiese) -10.1ogio (Thresholds, i, f) + C (r0) + F. (1-10) + 10.1ogio (r / r0) - 1-n where. r, I, are the coordinates of a point M,. lo denotes a reference linear distance,. r0 denotes a reference radial distance to the linear element,. P 'denotes the rate of linear losses along the aerial radiating from the distance Io,. -C (ro) denotes the losses by coupling in the band Bj at the reference radial distance r0 ,. ri represents a margin of caution taking into account the additional attenuations of the jamming signal during its propagation from the air to the forbidden terminal.