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Known device, having a receiving and a transmitting path, series-connected reference generator and amplifier, further includes series-connected spacecraft signal delay calculating path and clock signal generating path, wherein the first group of data inputs of the spacecraft signal delay calculating path is the adjustment bus of the device, N spacecraft signal generating paths, an adder and a digital-to-analogue converter, the output of which is connected to the data input of the transmitting path, the reference input of which is combined with the reference input of the receiving path, the output of the amplifier and the reference input of the clock signal generating path, the output of which is connected to clock inputs of the N spacecraft signal generating paths, the adder, the digital-to-analogue converter and the spacecraft signal delay calculating path, the n-th group of data outputs of which, where n=1, 2, …, N, is connected to the group of data inputs of the n-th spacecraft signal generating path, the first and second groups of data outputs of which are connected to corresponding groups of data inputs of the adder, the first and second groups of data outputs of which are connected to corresponding groups of data inputs of the digital-to-analogue converter, and the second data input of the spacecraft signal delay calculating path is connected to the data output of the receiving path. |
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Invention relates to radio engineering and can be used for radio-electronic protection of an object dislocation area from radar surveillance. The retransmitted jamming method includes receiving probing signals of the side-looking radar of each jamming station arranged around the periphery of the protected area; measuring the duration and repetition period of probing signals; generating repeatedly radiated interference, correlated with probing, in form of patterns of the received signals; introducing radiation delay of the patterns of the received signals and interference carrier frequency shift, measured according to a program from period to period of the repetition of probing signals; receiving signals of the radio navigation space-based system GLONASS; radiating said interference with oblique polarisation; picking up code signals from the structure of space radio signals; generating, when picking up code signals, reference pulse sequences and use thereof in jamming and synchronising jamming stations operating collectively. |
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Method for electronic jamming of radio communication system Invention relates to radio engineering and can be used to jam shipborne and airborne radio communication equipment. The method for electronic jamming a radio communication system involves using an aircraft as a jamming system carrier which is maintained on a "receiver-transmitter" line at the shortest possible distance from the receiver. The jamming system receives a probing information signal of the jammed system, reproduces carrier frequencies of the signal based on the signal and generates a noise signal, which is amplified and radiated towards the equipment being jammed. When radiating periodically with a period of about 3 s, pauses with duration of about 3 ms are made, during which the probing information signal of the transmitter is received and frequencies of the noise signals are refined when new carrier frequencies emerge. |
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High-speed optical line protected from eavesdropping by quantum noise Received power level of an optical signal in a link is monitored and matched with the transmitting side, selecting it to be maximally low, comparable to the level of optical quantum noise at the receiving side and where it is still possible to recover lost information bits while minimising optical losses in the optical line; a key for decrypting a bit data packet contained in the packet itself can vary from packet to packet and a cryptographic algorithm is selected such that decryption is impossible if a bit is lost from a data packet. The optical link comprises: a transmitter with an actuator, a receiving optical amplifier, a photoelectronic converter with an output narrow-band filter. |
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Invention relates to radio engineering and electronics and can be used to protect information of computer equipment, automated workstations and wire lines from information leakage as a result of stray electromagnetic radiation and cross talk. The noise signal generator has two outputs which are controlled based on signal strength. The additional noise signal generator used is an impact avalanche transit time noise diode with an amplifier and a variable resistor for controlling the additional noise signal strength, and the emitting low-frequency element used is an inductance coil with distributed parameters, which enables to generate the low-frequency part of the magnetic component o the electromagnetic field of the noise signal. |
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System for counteracting hostile radar station "antiradar" Invention relates to radar and systems for jamming a hostile radar station. The system comprises a receiving antenna aimed at the radar station, a radar signal amplifier, a multichannel transmitting antenna with radiators distributed on the front, and means of controlling radiation channels and pulse delay time, wherein the controlled delay line is connected between the amplifier and a channel switch, is multitapped and is equipped with a tap switch, wherein the number of the operating radiator(s) and the delay time are set by electronic switches from a control panel by an operator or through a program using a computer. |
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Method for jamming heterodyne-type short-range radar systems Invention relates to methods of jamming heterodyne-type short-range radar systems and can be used to design systems for active protection of objects from missiles and rockets equipped with short-range radar systems. The method of jamming heterodyne-type short-range radar systems involves determining the transmitter frequency of the short-range radar system and location thereof; analysing the obtained data with a computer and sending instructions to counteract the jamming the station, wherein the jamming station used is a monochromatic radiator, the signal frequency of which is set in the synchronisation band of the transmitter outside the frequency band of the receiver, and the power is selected higher than the power of the useful signal of the short-range radar system, thus tuning the transmitter of the short-range radar system to the frequency of the monochromatic radiation signal. Power consumed to jam the short-range radar system is about 15…20 times less than would have been consumed with direct jamming. |
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Repeater jamming method involves coherent reception of radio signals at a given frequency using antennae which form an antenna array, and a multichannel receiver, detecting a signal, generating and radiating interference from the far wave zone of the antenna array upon detecting a signal, wherein received radio signals at the moment of radiating interference are phased with compensation of phase incursion from the point of radiation to antennae; the phased radio signals are averaged on the set of antennae; the averaged radio signal is phased to restore the compensated phase incursions of the antennae; and formed difference radio signals are subtracted from the corresponding received radio signal at the moment of radiating interference, and at moments without interference radiation, the received radio signals are detected and averaged on the set of antennae, and signal detection is carried out by comparison with the detection threshold of averaged detection results. |
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Disclosed is a method of protecting the reading device for data medium in form of a card from unauthorised evaluation or copying of magnetically encoded data which are recorded on the reading device for the data medium in form of a card. A magnetic interference field is generated using an interference field coil. The arrangement of at least one interference field coil is such that an authorised magnetic reading head when reading magnetically encoded data on the data medium in form of a card is also under the effect of the interference field of the interference field coil. An output or resultant signal of the authorised magnetic reading head formed by the useful signal of the data medium in form of a card and the effect of the interference field is detected. The effect of the interference field of the interference field coil on the output or resultant signal of the authorised magnetic reading head is compensated for or filtered, or the useful signal is selectively filtered off from the output or resultant signal of the authorised magnetic reading head. |
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Method of detecting signals without carriers Method of detecting signals without a carrier involves dividing a digitised analogue signal into fragments which correspond to the number of elements of a predetermined digital sequence vector (DSV), inverting fragment readings, the number of which is determined based on a predetermined DSV consisting of N zero and unit values, wherein DSV values equal to zero correspond to fragments, the values of readings of which when inverted fully match values of readings of fragments corresponding to DSV values equal to one, after which a resultant sample is formed by arranging first readings of all fragments first, then second values and the last values at the end; the noise level threshold value selected is a value equal to double the mean-square deviation of readings of the resultant sample for positive and negative values of readings. Signal parameters are evaluated by comparing the sample with the noise level threshold value, wherein the signal parameters are maximum negative and positive values of the resultant sample, and a signal is detected if at least one of the parameters exceeds the threshold noise level on magnitude. |
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Method of protecting distributed random antenna Method of protecting a distributed random antenna involves connecting to a distributed random antenna through N interfacing devices N interference generators which protect the distributed random antenna, wherein M+K of the N interfacing devices include M amplitude modulators which, under the action of M of the N interference generators, perform stochastic amplitude modulation, as well as K angle modulators which, under the action of K of the N interference generators, perform stochastic angle modulation of information signals and interference generated by the distributed random antenna. |
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Information security apparatus for distributed random antenna Information security apparatus for a distributed random antenna, which is protected via a linear noise masking technique, has a multiplicative jamming device, a modulating signal former and a controlled parametric device, having a variable active resistance. The output of the multiplicative jamming device is connected to the input of the modulating signal former, the output of which is connected to the control input of the parametric device, which is connected to the distributed random antenna which is protected via a linear noise masking technique to facilitate amplitude modulation of the mixture of the confidential information signal and additive noise in the distributed random antenna which is protected via a linear noise masking technique. |
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Method of detecting radio-electronic equipment Method involves further multiplication and low-pass filtering of the output voltage of each antenna element with reference signal voltages corresponding to all antenna elements and presenting the multiplication and filtration results in form of a cross-correlation matrix of signals; performing corresponding multiplication, summation and subtraction operations with signals of corresponding elements of the cross-correlation matrix of signals to obtain the determinant of the cross-correlation matrix of signals; finding the maximum value of the determinant of the cross-correlation matrix of signals and, for the maximum value of the determinant of the cross-correlation matrix of signals, based on reference signal parameters, determining the frequency value and direction of arrival of the signal of continuously emitting radio-electronic equipment. |
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Method for functional jamming of digital electronic device Method for functional jamming of a digital electronic device involves generating a sequence of nano- or sub-nanosecond electromagnetic pulses and emission thereof towards the digital electronic device to be jammed, wherein the sequence of pulses is generated with stepwise increasing or decreasing duration of intervals between neighbouring pulses, wherein the minimum pitch of change in duration of said intervals is selected shorter than the period of the reference clock signal of the jammed digital electronic device, and the maximum pitch of change is not greater than the duration of the front of said reference clock signal. |
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Use of a limited number of types of an M-sequence in a data transmission system (for an M-sequence having pulse repetition period M of 32, there can be six such types) enables, in conditions without information on the type of the M-sequence used in a jamming station using multiple programmable matched filters in each receiving channel, to detect a signal of a data transmission system in each channel, and searchless techniques - instantaneous determination of the signal carrier frequency, enable to generate interference which is focused on frequency and bounded on code. |
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Device for detecting use of a laser acoustic location system for unauthorised pickup of speech information has a lens 1, the optical input of which is the input of the device, a tunable optical filter 2, series-connected photodetector 3, amplifier 4, control unit 5, the first output of which is the output of the device, and a device 6 for controlling the tunable optical filter, the output of which is connected to the control input of the tunable optical filter, as well as a power supply unit 7, the output of which is connected to power inputs of the photodetector 3, amplifier 4, control unit 5 and device 6 for controlling the tunable optical filter. |
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Resultant interfering signal is generated in a given region and eigen coordinates are measured. Composition of the orbital group of the global navigation satellite system used in the region and the number of properly functioning satellites are determined, while simultaneously receiving signals with navigation messages transmitted by the properly functioning satellites for all users of the global navigation satellite system in the region. The received messages are stored; navigation messages therein are distorted, after which a resultant interfering signal is generated in form of a plurality of signals with distorted navigation messages; the resultant interfering signal is synchronised with signals of navigation messages of satellites of the global navigation satellite system; the resultant interfering signal is emitted with power higher than that of legitimate signals of the satellites of the global navigation satellite system, wherein during prolonged operation, stored navigation messages are periodically updated. |
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Method involves generating a masking broadband noise signal using two noise signals with frequency spectrum division and subsequent summation of signals on the electromagnetic field by mixing the broadband noise signal with the clock signal of an information processing system. The apparatus includes a source of a low-frequency noise signal, a source of a high-frequency noise signal, a clock frequency unit of the information processing system, a mixer for mixing the noise signal and the clock frequency signal and an amplifier. |
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Method for information protection in distributed random antenna Distributed random antenna protection device has N interference generators (3) connected to the distributed random antenna through corresponding interface devices (2), and M nonlinear elements (4), where M is less than or equal to N, which are included in the distributed random antenna, wherein each of the M interface devices is connected to the corresponding nonlinear element, through which under the effect of M<N interferences, random integrated-differential frequency conversion of information signals and interference emitted by the distributed random antenna is carried out. |
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Method of receiving/transmitting cryptographic information Method of receiving/transmitting cryptographic information through global quantum key distribution employs an apparatus for synthesising a single-photon or a high-dimensional secret photon quantum key (SPQK) on Earth through an operation for input thereof into a fibre-optic line for transmitting the SPQK to a centre for directed secure transmission thereof to a low-orbiting spacecraft over a directed atmosphere channel with a coherent beam in the terahertz range, with another operation for transmitting the SPQK over a highly directional channel also with a coherent beam in the terahertz range or an optical laser beam to other spacecraft. Further, the final target secret operation is used to transmit the SPQK over the atmosphere channel in the terahertz range to ground-based parts for receiving information. During all operations for transmitting cryptographic information, SPQK are created using a random number generator. |
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Method to detect signals without carrier Received and digitised signal is divided into fragments of equal length. Then the second fragment is element-by-element added to the first fragment, and in the sum produced a time count of highest module is identified and saved. Afterwards in the second fragment the counts are shifted by one position so that the first one occupies the position of the second one, and the last one - of the first one, and after summation again the time count of highest modulation is identified and saved. The specified actions are repeated until the first count occupies the position of the last one, and the last one - of the last but one. Then the sum is chosen, to which the maximum of the saves values corresponds. Then the remaining fragments are similarly added to the selected sum. In the resulting summary fragment the negative and positive values of maximum module are defined as parameters of a digitised signal, which are compared with the threshold value of the noise level equal to the tripled value of the mean square value of time counts of the summary fragment. The decision on signal detection is made, if at least one of the identified parameters exceeds the value of the specified threshold. |
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Apparatus for generating radio interference Apparatus for generating interference generates an interfering confusion signal whose structure is similar to that of the transmitted signal, which will be perceived as a useful signal by a receiving device. A signal with convolution coding and a rate of 4/5 is an information packet consisting of three parts: an address, an information binary sequence and an attribute of the end of the information packet. The interfering signal is only distinguished by the information part which is replaced with a random sequence of pulses. |
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Analyser of parameters of a received signal, which is part of an existing radio monitoring station, comprises a limiting amplifier, a count pulse generator, a phase inverter, a differentiating circuit, a unidirectional gate, two pulse counters, two coincidence elements, a code comparator unit, two adders, a subtractor, a pulse counter and a divider unit, connected in a certain manner to each other and a to corresponding equipment of the existing radio monitoring station. |
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Method for information protection of random antenna Method for information protection of a random antenna using a system of jamming emitters involves placing M transponders of the information signal emitted by the random antenna between the random antenna and fixed intercepting equipment. The transponders are connected to amplitude and angular modulators which are connected to M jamming generators which perform stochastic amplitude and angular modulation of the information signals emitted by the random antenna. The fixed intercepting equipment includes N information signal receivers and a computer circuit for processing received signals. |
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System for secure telephone communication System for secure telephone communication has telephone receivers, subscriber lines (SL), a line input unit, a first switching unit, a signal analysis unit, an automatic telephone exchange (ATE), as well as a program control unit, an automatic vocoder unit (AVU), an interfacing unit, a second switching unit, an interaction and control signal unit (ICS), first and second cryptographic units, a channel input unit connected to long distance channels (LDC), a subscriber telephone terminal (STT) and a digital subscriber line. The system also includes a line input unit, a program control unit, an AVU, an interfacing unit, an ICS unit, a second cryptographic unit, a channel input unit connected to LDC, STT and a digital SL; the ATE consists of a subscriber line unit, a jack field unit, a server unit, a workstation unit, a channel set unit and a station control unit, which includes a first, a second and a third peripheral control unit, a random access memory unit, a central control unit, a program storage unit and a program replacement unit; connections between existing units have also been changed and they have additional functions. |
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Method for information protection of distributed random antenna Invention relates to protection of confidential information and can be used to protect radio systems associated with the term "distributed random antennae". The method for information protection of a distributed random antenna involves connecting interference generators to the distributed random antenna through N interface devices, said interference generators providing information protection for the distributed random antenna. M of the N interface devices include M≤N amplitude modulators which, under the action of M interference generators, perform joint random amplitude modulation of information signals and interference emitted by the distributed random antenna. |
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Radio monitoring station has an antenna device, a receiver, a direction finder, a received signal parameter analyser, a device for storing and processing the obtained information and a telemetering device, three receiving antennae, an adjustment unit, two heterodynes, four mixers, three first intermediate frequency amplifiers, a detector, three delay lines, a switch, a second intermediate frequency amplifier, five multipliers, three narrow-band filters, a phase detector, two phase meters, two 90° phase changers, two low-pass filters, two squaring devices, an adder and a threshold unit, connected to each other in a certain manner. |
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Radio engineering monitoring station Device comprises an antenna device 1, a receiver 2, a finding device 3, an analyser 4 of received signal parameters, a device 5 to memorise and process received information and a telemetric device 6, the receiver 2 comprises a tuning unit 10, heterodynes 11, 23, mixers 12, 24 and 46, amplifiers 17 and 47 of the first intermediate frequency, a detector 20, a delay line 21, keys 22 and 53, an amplifier 25 of the second intermediate frequency, narrow band filters 36 and 51, phase inverters 38, 41, 44, and 49, phase changers 45 and 48 at 90°, multipliers 50, 59 and 60, amplitude detectors 52 and 54, a device 55 to generate a frequency reamer, oscillographic indicators 56 and 63, a delay line 57, filters 61 and 62 of lower frequencies, the finding device 3 comprises mixers 13 and 14, a motor 15, a reference generator 16, amplifiers 18 and 19 of the first intermediate frequency, multipliers 26, 27, 30, narrowband filters 28, 29, 32, a delay line 31, a phase detector 33, phase meters 34 and 35. |
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Method and device for message transfer using fibonacci p-codes Device for message transfer using Fibonacci p-codes contains a processor (via a bi-directional control bus connected to the general-purpose register to the serial input whereof a receiver is connected) as well as a transmitter and a clock frequency generator and (serially connected) a pseudorandom sequence builder and the transmitter Module 2 addition circuit, the pseudorandom sequence register. The method describes this device work. |
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Device for generating interference Device for generating interference has a receiving antenna, a receiving-exciting unit, a radio transmitting unit with a transmitting antenna, a unit for generating interference and a control unit, a unit for generating interference, a timing unit, a pseudorandom sequence generator, a unit for radio suppression of discrete communication channels. |
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Method of radio suppression of communication channels Signals of radiation sources are received, their parameters are identified, signals are generated to control the transfer mode, and using the structure of modulating voltages, noise signals are modulated, amplified, radiated, at the same time the received signal time is measured, during which it exists at i frequency, the minimum value is extracted from the number of measured time intervals and accepted as an interval of noise emission time, and the noise is emitted every time whenever the source signal is detected at one of its working frequencies within the time cycle of suppression. |
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Original message M is generated in form of a non-commutative finite group G based on Cayley algebra while performing modulo operations over a prime number p; a secret encryption key is generated in form of pairs of elements X and X-1 of group G and a multidigit number e; the initial cryptogram Y is generated by generating an element R of group G by raising the original message M to the power of e; an element V of group G is generated by performing a group operation over elements X and R of group G and subsequent group operation over elements V and X-1 of group G; a cryptogram C is generated in form of an element G by y-fold performance of an operation similar to the operation of generating the initial cryptogram Y, except that on each i-th step, elements Xi and X-i are used as elements X and X-1 of group G, respectively, and the result of the previous operation (Y, Y1, Y2, …, Yi) is used instead of element M. |
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Radiocommunication method is based on emission, along with useful signal, an interfering signal of comb-shaped structure with spectral and energy characteristics similar to spectral and energy characteristics of useful signal, and on receiving side, useful signal filtration against interfering emission. |
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Apparatus for protecting computer hardware of information technology facilities from stray electromagnetic radiation has a radio camouflage device, a spectrum analyser, a switching unit, electrically alterable read-only memory and a probabilistic forecasting device. |
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Method for coherent interference formation FIELD: radio electronics. SUBSTANCE: device for coherent interference formation contains two antennas, two decoupling units, two digital data storages, two bandpass digital radio-frequency transformers, two phase inverters, two operation mode switch gears, two bandpass radio-frequency digital transformers, two attenuators, two amplifiers, two calibration signal generators, coherent interference modulator, two measuring sets of complex amplification coefficient, two Doppler modulators, electronic reconnaissance system, control CPU, bank of compensating adjustments. EFFECT: increased effectiveness of coherent interference formation in the wide range of electronic warfare system frequencies. 1 dwg, 3 dwg |
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Method of transmitting and receiving signals Method involves simultaneous emission of several amplitude- and phase-shift keyed useful signals and a masking signal, summation thereof and suppression of the masking signal during reception, wherein the masking signal emission used is not only similar to the useful signal on polarisation, spatial, time and frequency parameters, but also overlaps the frequency variation range of each useful signal emission; two reference signals with equal initial phases are generated, wherein all parameters of one of them coincide with parameters of the emitted useful signal, and the second reference signal is distinguished only by carrier frequency; a mutual correlation function is generated between the receiving additive family of the masking signal and the corresponding reference signal, and the second mutual correlation function is subtracted from the first. |
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Method of radio suppression of communication channels After replacement of a transfer frequency from a source of messages for a specified mobile subscriber, additionally a channel type is determined, as well as a frequency channel number and a number of a time window in a frame. And when a telegraph mode is used, in which signals are used with time interleaving, a noise signal is radiated within the suppression cycle at the frequency of mobile subscriber transfer only at the moments of time, which are strictly determined by the number of the time window in the frame. |
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Detection of preambles and synchronisation in ofdma-systems of wireless communication Symbol correlation of symbols sequence is calculated in a correlation window with the help of one of time area correlations and frequency area correlation. Sequence of symbols is received according to the method of wireless communication with multiple access with orthogonal frequency division of channels (OFDMA). The symbol is verified from a symbol correlation. The symbol is one of a preamble symbol and a data signal. |
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Method is carried out by reduction of probability of recognising transmitted data in a communication line. The method to protect information in a communication line against leakage due to external electromagnetic radiation and noise consists in the fact that digital signals transfer along a communication line is terminated. Then this line is complemented with an additional line, and masking signals are sent synchronously together with the transfer along the secured line along this additional line. Besides, amplitude and frequency-time parameters of masking signals are selected so that the picture of external electromagnetic radiations and noise from both lines as a whole that occurs in environment in process of data transfer, is identical for each pulse of transmission. |
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Temporary radio base station (RBS, 140) is positioned in or adjacent to the targeted RBS (120), and transmits at a frequency in the candidate list of the targeted RBS (120). The transmissions are at such a power level that the traffic of the targeted RBS (120) is transferred to the temporary RBS (140). The temporary RBS transmits the identification signal the RBS whose frequency the temporary RBS transmits at, and transmits a list of candidate frequencies such that user terminals whose traffic has been transferred to the temporary RBS cannot find signals with sufficient strength on any of the candidate frequencies. |
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Fibre-optic data transmission system with unauthorised access protection Fibre-optic data transmission system with protection from unauthorised access has a transmitting and a receiving part connected by a fibre-optic channel, the transmitting part comprising a parallel data input bus, a pulse former, M matching amplifiers, M transmitting optoelectronic modules, M fibre-optic delay lines, an optical spectrally-selective coupler and an optical amplifier, a parallel N bit register, a memory device, and the receiving part comprising an optical spectrally-selective splitter, a fibre-optic delay line, a receiving optoelectronic module, a parallel data output bus consisting of N data lines and clock lines, (M-1) fibre-optic delay lines, (M-1) receiving optoelectronic modules, an OR logic element and a second memory device. |
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Method consists in generation of a noise signal and its mixing with an additional signal with subsequent use of a signal produced as a result of mixing as a masking signal, an additional signal is a clock signal of the information processing system (IPS). The device comprises a noise signal generator, an amplifier, a signal frequency converter, such as a unit of the information processing system clock frequency, and a signal frequency converter is a mixer of a noise signal and a signal of the information processing system clock frequency. |
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Generation method of chaotic high-frequency and super high-frequency broadband oscillations Generation method of chaotic high-frequency and super high-frequency broad-band oscillations is characterised by the fact that it involves formation of laminar electron flow, its conversion to turbulent flow by modulation owing to impact of non-homogeneous electric and magnetic fields, amplification of chaotic broad-band high-frequency and super high-frequency oscillations of turbulent electron flow and their pickup through output of HF and SHF energy. |
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Mobile station of confidential telephone communication Mobile station of confidential telephone communication additionally includes subscriber lines (SL) and four-wire connecting lines (CL), the first and the second unit of the cable input (CI), a unit of subscriber cross, a unit of cross-switching of information flows (IFCC), the second cryptographic unit, a telephonic gateway with a connected liquid crystal display and a keyboard, a four channel basic station of DECT system and one and more special microcellular telephones with cryptosecurity and an inbuilt antenna. |
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Helicopter radio-electronic complex Helicopter radio-electronic complex includes check point and aircraft equipment of helicopter that consists in series connected antenna device (1,) receiver (2), analyser (4) of received signal parametres, storage and received information processing device (5), the second input of which is connected to receiver output (2) through direction-finding device (3), and telemetering device (6). Receiver (2) includes first receiving antenna (7), first mixer (12), heterodyne oscillators (11 and 23), amplifier (17) of first intermediate frequency, reformation unit (10), delay line (21), detector (20), key (22), second mixer (24) and amplifier (25) of the second intermediate frequency. Direction-finding device (3) includes mixers (13 and 14), engine (15), frequency generator (16), amplifier (18 and 19) of first intermediate frequency, multipliers (26, 27 and 30), narrow-band filters (28, 29 and 32), delay line (31), phase detector (33), phase metre (34 and 35). Antenna device (1) includes receiving antennae (7, 8, 9), transmitting-receiving antenna (44) of telemetering device. Note that receiving antenna (7) of receiver (2) and transmitting-receiving antenna (44) of telemetering device (6) are located above helicopter rotor head, receiving antennae (8 and 9) of direction-finding device (3) are located at the ends of helicopter rotor blades. Telemetering device (6) includes first driving generator (36), analogue message former (37), first analogue scrambling device (38), first amplitude modulator (39), discrete messages forming device (40), first digital scrambling device (41), first phase manipulator (42), power amplifiers (43 and 62), forth (58) and fifth (63) heterodyne oscillators, sixth (59) and seventh (64) mixers, amplifier (60) of third intermediate frequency, first duplexor (61), second amplifier (65) of forth intermediate frequency, second amplitude limiter (66), second synchronous detector (67), second analogue scrambling device (68), second band-pass filter (70), third phase detector (71) and digital scrambling device (72). Check point includes second transmitting-receiving antenna (45), high frequency amplifiers (46 and 83), third heterodyne oscillator (47), fifth mixer (48), first amplifier (49) of forth intermediate frequency, first amplitude limiter (50), first synchronous detector (51), first analogue descrambling device (52), registration and analysis unit (53), forth multiplier (54), first band-pass filter (55), second phase detector (56), first digital descrambling device (57), analogue messages source (73), second analogue scrambling device (74), second driving generator (75), second amplitude modulator (76), discrete message source (77), second digital scrambling device (78), second phase manipulator (79), sixth heterodyne oscillator (80), eighth mixer (81), amplifier (82) of intermediate frequency, second duplexor (84). |
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External artificial optical noise at acoustic frequencies is entered into the optical cable of standard information transmission systems. The apparatus for implementing the active protection method has a light source with a fibre optic output that generates optical radiation with a noise spectrum at acoustic frequencies. |
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Method involves generation of artificial noise, noise masking, masking light flux in fibre-optic communications on acoustic frequencies, and the apparatus which implements the active protection method comprises a power supply and an audio playback device (audio player, generator) which can be electrically connected to an optical radiation modulator which uses vibrational, acousto-electric, electro-optical and magneto-optical methods of modulation. |
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Method of coding includes the following sequence of actions: final group G is generated, message is formed in the form of element M of final group G, secret coding key is generated, cryptogram is generated in the form of element C of final group G by conversion of message M depending on secret key of coding, besides, as final group G a non-commutable final group is generated, secret coding key is generated in the form of two elements X and W of group G and multi-digit binary number e, cryptogram C is generated by formation of element R of final group G, equal to e extent of message M, i.e. R=Me, formation of element V of final group G depending on elements X and R of final group G and subsequent performance of group operation between elements V and W of final group G. |
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Radio communication scrambling method Invention relates to radio communication. Clock pulses are introduced into a frequency modulated (FM) radio signal of the transmitter of a first radio station several times a second, for which the carrier frequency is frequency modulated at a frequency which is several times higher than the maximum frequency of the signal. This clock pulse is picked up in the receiver of a third radio station and the distorted signal is restored relative said clock pulse in the receiver of the said third radio station to the initial signal, on one algorithm for introducing distortions and rearranging time parts of the signal for all radio stations, where during time intervals between the clock pulses of the signal transmitted by the transmitter of the first radio station on a signal arbitrarily broken down in time, distortions are either introduced or parts of the signal are rearranged in a certain order for all radio stations. The receiver of the first radio station constantly monitors availability of clock pulses of a second radio station switched on for transmission earlier, and if the first radio station goes on air during operation of the second radio station, the synchrosignal of the said second radio station is used, for which during that time the first radio station is momentarily switches to the synchrosignal receiving mode during the synchrosignal on its inner synchronisation on a previously received sychrosignal of the second radio station, independent of its own signal transmission, and if the synchrosignal of the second radio station disappears, the first radio station begins to transmit its own synchrosignal. Temporary interruption of transmission of the synchrosignal of the first radio station and use of internal synchronisation by the first and third radio stations is allowed. |
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Noise source for vibro-acoustic masking facilities Noise source has an electroacoustic transducer and an electric noise signal generator. The source also has an electro-vibration transducer. The housing of the noise source and the electroacoustic transducer form a resonant chamber and the electro-vibration transducer is rigidly mounted on the inner wall of the base of the housing of the noise source. The noise generator is double-channel programmable, with possibility of simultaneous operation of both channels or one of them. The output of the first channel of the generator is connected to the electroacoustic transducer, and the output of the second channel is connected to the electro-vibration transducer. The eletroacoustic transducer and electro-vibration transducer are piezoceramic transducers. |
Another patent 2513412.