99 results about "Military communications" patented technology

An intelligent communications capability that enhances legacy military tactical datalink systems by creating an interface between disparate civil and military communications systems onboard military aircraft, ground vehicles, and ground-based communications infrastructures. This capability performs various information management tasks to interface with avionics systems, ground vehicle computer systems, and ground-based infrastructure computer systems. The invention enhances message processing through automation in areas such as data collection, incoming message handling, outgoing message construction, communications network management, and message priority management and routing. The invention also incorporates learning techniques to improve the overall efficiency of integrated military missions, operations, and maintenance in areas such as intelligent consolidation of datalink information, intelligent message distribution, and adaptive message re-routing in response to communications network failures. These enhancements will benefit the military by improving mission effectiveness with real-time information integration and management while reducing their support costs.

In one aspect, a hybrid airship including an outer shell, a plurality of helium filled gas envelopes, and an all-electric propulsion system may have the shape of a delta-wing. In some embodiments, the hybrid airship may be launched using buoyancy lift alone and aerodynamic lift may be provided by the all-electric propulsion system. In one aspect, a photovoltaic array and a high energy density power storage system may be combined to power the propulsion system making the propulsion system regenerative. The delta-wing shape can provide a surface area large enough to accommodate very large circular or elliptical transmission devices. By continuously recharging the power storage system, the hybrid airship in accordance with some embodiments can stay aloft at an operational altitude of at least about 85,000 ft for months or even years. The hybrid airship may function as an airborne military communications relay platform.

A modulation recognition method and device for digitally modulated signals with multi-level magnitudes are provided. The modulation recognition method includes selecting plural of quantization sizes used to construct plural of statistic histograms related to the magnitude of a sequence of data, setting up an off-line processing to extract plural of useful feature patterns for each modulation type of interest, receiving a sequence of samples of the modulated object signal and constructing plural of statistic histograms related to the magnitude of these samples, and adopting a hierarchical classification method for modulation recognition. It can be applied to the adaptive-modulation communication system, software defined radio, digital broadcasting systems and military communication systems. It can also be integrated with modulation recognition techniques for other types of modulated signals to function in a universal demodulator. It recognizes digitally modulated signals of multi-level magnitudes with low computational complexity in advancing the efficiency of communication systems.

A method for communicating in a wireless communications system includes receiving an indicator indicating a utilization of network resources for carrying an acknowledgement information, and determining whether the station is permitted to transmit a packet. The method includes when the station is permitted to transmit the packet, determining a first location of a first network resource in accordance with the indicator, and transmitting the packet at the first location of the first network resource.

The invention discloses a distributed semi-physical network simulation system and a controlling method of semi-physical port thereof, comprising a network physical system and a network simulation system, wherein the network physical system comprises a plurality of network nodes and communication connecting equipment thereof based on military communication network; the network simulation system comprises a plurality of simulative PC machines operated with network simulative software, each simulative PC machine in the network simulative system has a semi-physical port; under the condition that the semi-physical port finishes the functions of information analysis, transmission and time management between the network simulation systems and between the network simulation system and the networkphysical system without changing any arrangement of simulative and physical system, the different simulative applications such as simulation and physical are connected with each other, each simulativePC machine has the semi-physical port, and the expandability of the system is strong.

The invention discloses a protection device of an Ethernet passive optical network (EPON) system and a data redundancy backup method and a monitoring method. A data redundancy backup device comprises an optical line terminal (OLT) downlink data processing module, an optical network unit (ONU) downlink data de-encapsulation module, an ONU uplink data processing module and an OLT uplink data de-encapsulation module, the protection device of the EPON system is also provided with a monitoring module, and the data redundancy backup method and the monitoring method are realized through the monitoring module. One optical-fiber full-protection device and one data redundancy backup device are added on an OLT device and an ONU device, so that the hand-in-hand optical-fiber full-protection in the EPON system can be realized, the zero-millisecond master and slave switching of the optical fiber can be realized, the zero business interruption is realized, redundant data backup is also provided, and the monitoring module can detect failure of a media access control (MAC) chip and other circuits; and the maintainability of the system is greatly improved. The high-reliability application places in the application fields such as military communication, industrial real-time control, security protection, and video monitoring can be satisfied.

The invention discloses an instantaneous frequency measurement method based on the adaptive filtration theory. The adaptive filtering algorithm is utilized to decompose a nonstationary multi-frequency component signal into a plurality of progressive single-frequency signals to be measured, thus solving the analyzing problem of the multi-frequency component signal. The Hilbert transformation is adopted to perform instantaneous frequency measurement to the progressive single-frequency signals, thus complete and accurate instantaneous physical quantity of the nonstationary multi-frequency component signal can be obtained, the time-frequency distribution of the nonstationary signal can be further obtained and the requirements of instantaneous frequency measurement in the fields of military communication and electronic countermeasure can be satisfied.

The invention relates to a data flow-based deterministic network integrity fault detection method. The method includes the steps of: according to a topological structure of a whole deterministic network, establishing a data flow-based triad model; by determining a priority relation of data integrity, source integrity, order integrity and time integrity, analyzing granularity required by a user, and aiming at hardware faults, logic faults and configuration information faults, making a fault mode analysis; on this basis, performing fault tree analysis, proposing a measurable and computational bottom event probability acquisition method, and performing qualitative and quantitative calculation; and finally completing fault detection. Aiming at the problem that a conventional fault detection method serial-parallel model cannot complete fault positioning in practical engineering, the problems of deterministic network data accuracy and integrity fault detection are solved. A method having engineering value is provided for integrity research of deterministic networks such as an aviation airborne network, an industrial control network and a military communication network.

The invention relates to a DSSS / UQPSK signal pseudo code sequence estimation method based on characteristic decomposition and the Messay algorithm, and belongs to the technical field of communication. The estimation method includes the steps that segmentation is carried out according to a long code cycle, segmentation is carried out on each segment according to the information code element width, a short code sequence and long PN code sequences of all the segments are obtained according to a characteristic decomposition method, a part of the long PN code sequences of all the segments are selected for solving a generator polynomial, and the long PN code sequences of the whole cycle are recovered according to the generator polynomial. According to the DSSS / UQPSK signal pseudo code sequence estimation method, the efficiency of PN code estimation is improved, besides, accuracy of PN code estimation is improved, and the problem of phase ambiguity when the long code sequences are recovered can be effectively solved. No prior knowledge requirement is made for the own characteristics of PN codes, and people only need to know the cycle of the long PN codes and the cycle of short PN codes. The DSSS / UQPSK signal pseudo code sequence estimation method has application prospects in multiple fields such as radio management, military communication reconnaissance and interception and coherent jamming.

The invention discloses a dual-sensor voice enhancement method based on a statistics model and a device. The method comprises steps of combining non-air-conduction sensor voice with air-conduction voice to construct a voice combined statistic model for classification and performing terminal detection, calculating the optimal air-conduction voice filter through the classification result of the combined statistic model, performing filtering enhancement on the air conduction voice, converting the non-conduction voice to the air conduction voice with the air-conduction characteristic through the mapping model, performing weight fusion in order to improve the voice quality. The method adopts the two-stage voice enhancement structure method. When the filtering effect of the air conduction voice is not good because of the strong noise, the second stage voice enhancement performs adaptive weight fusion on the mapping voice filtering voice of the filtering voice and the non-air-conduction voice, so that the better voice enhancement effect can be obtained under the strong noise environment. The method disclosed by the invention can be widely applicable to the video communication, the vehicle-mounted telephone, the multimedia classroom, the military communication, etc.

The invention discloses a digital signature proposal based on ECC. Scalar multiplication of an elliptic curve, point addition and Montgomery field modulo algorithm, etc. are usedfor realizing fast digital signature and signature verification. In the proposal, a method for replacement is adopted for treating random numbers which do not meet requirements, thus preventing the process for generating the random numbers again; the methods such as the replacement, interception and zeroizing are adopted to treat hash values, thus preventing frequent switch between large prime field and Montgomery field; the operations of signature and verification are basically in the Montgomery field, thus preventing time-consuming operation of modulo reduction. The digital signature proposal can be used in environments such as e-business, content protection interface, banking system, military communication, and intellectual property right protection, etc.

The invention discloses a multifunctional serial voltage-stabilizing power supply. A battery pack is connected with a charging and discharging control circuit, the output end of a transformation and rectification filtering circuit is connected with the input end of a primary voltage-stabilizing circuit, the output end of the primary voltage-stabilizing circuit is connected with the input end of the charging and discharging control circuit and the input end of a secondary voltage-stabilizing and intrinsically safe circuit, the output end of the secondary voltage-stabilizing and intrinsically safe circuit is connected with the input end of a triple voltage-stabilizing and intrinsically safe circuit, and an overvoltage protection circuit is arranged between the output end of the secondary voltage-stabilizing and intrinsically safe circuit and the input end of a triple voltage-stabilizing and intrinsically safe circuit. The power supply can be applied to underground occasion containing explosive mixed gas and military communication occasion and can operate for a long term, resist high and low temperature, carry out short circuit on the output end of the voltage-stabilizing and intrinsically safe circuits for a long time and has improved function, excellent watertight and anti-explosion performances and extremely high reliability after running for a long time.

The invention discloses a coupled cross resonator based reconfigurable differential band-pass filter which comprises two mutually-coupled micro-strip cross resonators. The mutually-coupled micro-strip cross resonators are bilaterally symmetrical relative to the longitudinal neutral axis of the filter, and each micro-strip cross resonator is formed by combining three micro-strip transmission lines. The coupled cross resonator based reconfigurable differential band-pass filter is of a simple and easily-achieved micro-strip transmission line structure and is light in weight, small in size, high in processing speed and low in cost, differential-mode filtering center frequency, differential-mode filtering response band width, differential-mode filtering selection characteristic, common-mode rejection range and common-mode rejection capacity of the filter can be very conveniently reconfigured by welding lumped capacitors different in capacitance value so as to meet the requirements for communication devices of different systems and different environments. The coupled cross resonator based reconfigurable differential band-pass filter has wide research and development prospect on design of frequency modulation communication devices, communication devices in complicated environments and civil or military communication devices having high common-mode noise suppression requirements.

The invention discloses a coding error correction based secret key forward direction consistency calibration method, belongs to the field of communication safety and relates to a secret key generating technology in a communication system. The coding error correction based secret key forward direction consistency calibration method is used for improving the inconsistency on secret key generation of the communication system, a safe frame structure, a secret key calibration method and a secret key update method are provided, and the safety problem in secret key generation and negotiation is solved. The coding error correction based secret key forward direction consistency calibration method is used for strengthening the safety of the communication system, can be specifically applied to the fields of safe communication, military communication and the like and can be extended to a multiple-node communication scene.

The invention belongs to the field of wireless communication and military communication, and discloses a synchronization frame structure and a synchronization method suitable for short burst communication time-frequency joint synchronization. Coarse timing synchronization is completed by utilizing same short synchronization training sequences on a plurality of antennas, and the method comprises the following steps: performing shift correlation on a local short training sequence and a received signal, and finding a position where a maximum peak value is located as a coarse timing synchronization position; utilizing correlation between the cyclic prefix of the data part and the data tail part to correlate the CP length, taking the phase value of the correlation value at the coarse timing synchronization position to obtain a relative frequency offset value, and then carrying out frequency offset correction; and finally, carrying out shift correlation in a coarse timing synchronization (-CP, + CP) (CP refers to a cyclic prefix) range by using a local long training sequence and a received signal to obtain fine timing synchronization. Compared with the existing frame structure design, the synchronization frame structure and a synchronization method has the advantage that the timing synchronization accuracy is greatly improved.

The invention relates to an underwater acoustic communication method based on very minimum chirp keying modulation. The method comprises that: a transmitter drives an underwater acoustic transducer by using a very minimum chirp keying modulated ultra-narrowband signal as a transmission signal source to generate chirped longitudinal waves for transmission in water; and a receiver converts an acoustic signal into an electric signal for demodulation by the transducer. By the method, a frequency band utilization rate is extremely high. The communication method is applied to underwater acoustic communication and aims to explore a new technical path for the underwater acoustic communication, realize high-speed underwater acoustic information transmission and increase the frequency band utilization rate in a signal transmission process. The method is expected to be applied to future submarine military communication.

The invention discloses a digital communication station device with multi-carrier frequency hopping, comprising a communication carrier random indication unit, a baseband processing unit, a transceiver frequency conversion unit, a communication carrier searching unit and a duplexer. According to the scheme of the invention, in a station communication process, the communication carrier random indication unit randomly changes indication information to ensure that the communication carrier frequency is in a hopping state, a communication channel that loads voices and data is also in a random hopping state in a communication bandwidth, and a pseudo noise channel disguises and conceals the communication channel; and the multi-carrier frequency random hopping mode improves the anti-interferenceability of communication, avoids the defects of poor anti-interference ability and easy interception of existing analog communication stations and digital communication stations in a complex electromagnetic environment, also solves the problems that need to be solved in an actual frequency hopping communication process, and is applicable to data transmission and voice communication in various confidential anti-interference scenes such as civilian private network communication and military communication.

An Ad Hoc network is a multi-hop temporary autonomous system consisting of a group of mobile terminals with wireless transceiving devices. The Ad Hoc network has excellent properties that traditional networks do not have, and the excellent properties enable the Ad Hoc network to have wide application prospect in the fields of military communication, disaster relief, temporary communication and the like. Because the Ad Hoc network has dynamic property and each terminal has low transmitting power, small communication bandwidth, limited energy and the like, a key exchange protocol in the Ad Hoc network must have the properties of dynamics, as little communication amount and calculation amount as possible and the like. The key exchange protocol of the invention not only has dynamic property and certifiable security, but also has smaller communication amount and calculation amount compared with the conventional schemes, so the key exchange protocol has higher application value in the Ad Hoc network. The scheme also can be used in the traditional networks.

The invention belongs to the technical field of microwave antennas and relates to a broadband low-RCS patch antenna based on an FSS transmission and passive reflection cancellation technology. The patch antenna comprises a parasitic patch, an excitation patch, an antenna ground plate, a first dielectric substrate, a second dielectric substrate, an SMA probe joint and a conductor of the SMA probe join which jointly form a patch antenna part; an upper FSS patch, a lower FSS patch and the second dielectric substrate form a double-layer FSS structure part; and a first AMC patch group, a first AMCpatch group and the first dielectric substrate form a mixed AMC surface part. According to the broadband low-RCS patch antenna, two resonances of the double-layer radiation patch can be excited, so that the impedance bandwidth of the patch antenna is broadened; and transmission performance and the wave absorbing performance of a metamaterial absorber can be combined to realize a low RCS characteristic in a broadband range, so that the antenna can be applied to shipborne, airborne and vehicle-mounted military communication systems, and can also be applied to an intelligent skin system to realize stealth and communication functions.

The invention discloses a transmitting antenna number blind estimation method applicable to an MIMO (Multiple Input Multiple Output) system, and mainly solves the problem of low accuracy of identifying a number of transmitting antennas of the MIMO system in a time-variant fast fading channel environment and under the condition of a low signal-to-noise ratio. The method comprises the steps of: (1) constructing a received sample matrix by utilizing a received signal of a non-cooperative receiving machine, and implementing data acquisition of the non-cooperative receiving machine; (2) constructing a covariance matrix by utilizing the received signal sample matrix; (3) carrying out feature value decomposition on the covariance matrix; (4) setting a bilateral detection threshold, and initializing a counting variable; (5) calculating a second-order moment; (6) calculating a feature value judgment threshold; and (7) according to a feature value and a threshold, carrying out judgment to obtain the number of the transmitting antennas of the MIMO system. According to the transmitting antenna number blind estimation method disclosed by the invention, a correct identification rate in a fast fading channel under the condition of small sample received data and under the condition of the low signal-to-noise ratio is ensured, and applicability in military communication resistance and in the time-variant fast fading channel is ensured.

The invention discloses a wireless channel characteristic stepwise quantification method based on unitary transformation preprocessing. The method comprises the following steps: making a party A and a party B in wireless communication perform unitary-transformation-based preprocessing on channel detection results; quantifying preprocessed signal vectors with different signal-to-noise ratios with different quantification levels; and finally, using generated quantification bit streams as inputs of subsequent wireless channel key generation steps such as an information reconciliation step. Through adoption of the method, the consistency of the channel detection results of the party A and the party B in the wireless communication can be improved effectively; the auto-correlation of the channel detection results is lowered; and the two parties of the communication can generate quantification bit streams with high rate, high consistency and low redundancy. The method is applied to the field of wireless channel key generation, can be specifically applied to the fields of secure communications, military communications and the like, and can be extended to a multi-node communication scene. Through adoption of the method, the security of a wireless communication system is enhanced.

The invention discloses a non-electric full-automatic gas-liquid rotary spraying fire extinguishing device for a military communication shelter. The non-electric full-automatic gas-liquid rotary spraying fire extinguishing device comprises a rotary spraying mechanism and a bracket mechanism, wherein a bracket mechanism is fixedly arranged at the bottom of the rotary spraying mechanism; the rotary spraying mechanism comprises an upper end cover, a lower end cover, a flow divider, a connection opening, a heat insulation sleeve and a driving component. The non-electric full-automatic gas-liquid rotary spraying fire extinguishing device for the military communication shelter is suitable for places such as the military communication shelter, does not need power driving and can be automatically switched on and switched off according to the fixed characteristics of a memory alloy; the memory alloy is separated from the outside through the heat insulation sleeve, so that the phenomenon that a memory alloy spring switches off a sprayer too early because the temperature of a fire extinguishing agent is too low is avoided; the device can be quickly started, and all-round spraying is realized; the fire extinguishing effect is outstanding.

The invention discloses a channel reciprocity enhancement method based on principal component analysis. The method comprises the following steps: firstly, wireless communication both parties Alice and Bob independently collect the measurement values of uplink and downlink channel characteristics; then, the collected measurement values of the uplink and downlink channel characteristics are independently subjected to sample grouping division to obtain channel characteristic sample groups; the wireless communication parties Alice and Bob carry out principal component analysis processing on each channel characteristic sample group; and finally, a processing result with high reciprocity is obtained. By use of the channel reciprocity enhancement method, the problems of the reciprocity reduction of the measurement values of the channel characteristics due to measurement noise and environmental noise and insufficient randomness of a secret key generated by a wireless channel due to high correlation between the measurement values are solved. The channel reciprocity enhancement method is used for enhancing the safety of a wireless communication system, can be specifically applied to fields including secure communication, military communication and the like, and can be expanded to a multi-node communication scene.

The invention discloses a miniaturized high-gain dual-band circularly-polarized antenna which is simple in structure and can realize miniaturization, dual frequency band, high gain and right-handed circular polarization, the bandwidth of the antenna is increased, and the gain of the antenna is improved. The miniaturized high-gain dual-band circularly-polarized antenna comprises an insulating medium substrate, a radiating body and a U-shaped metal back cavity; a first T-shaped slotted hole, a second T-shaped slotted hole, a third T-shaped slotted hole and a fourth T-shaped slotted hole which extend from the center of the radiating body to four sides of the radiating body and circumferentially uniformly distributed along a circle using the center of the radiating body as the center of the circle are formed in the radiating body; a first rectangular slotted hole and a second rectangular slotted hole are formed in the diagonal line of the radiating body, the first rectangular slotted hole is internally provided with a first T-shaped radiating body, and the second rectangular slotted hole is internally provided with a second T-shaped radiating body. By adopting the miniaturized high-gain dual-band circularly-polarized antenna, the requirement of military communication mobile phone antennas can be met, and the antenna is conveniently placed on the top of the communication mobile phone antenna, so that cover lifting is realized.

A military communications unit that utilizes a relatively high-bandwidth digital communication networks (e.g., cellular networks) is capable of acting as a wireless communications hub for a soldier, vehicle, weapon, or other entity. The military communications unit can obtain data from multiple devices via close-range wireless technologies and communicate with training or operational networks. The military communications unit can be flexible in its capacity to relay data by formatting data in accordance with Distributed Interactive Simulation (DIS), High-Level Architecture (HLA), and / or another distributed computer simulation standard. Moreover, the military communications unit may be further capable of “re-banding,” enabling communications using cellular protocols and / or standards in non-cellular frequency bands.

The invention provides a data transmission method and a data transmission device. The data transmission method comprises the following steps: a sender establishes N different first paths between the sender and a receiver of a default network; the sender splits a data frame of fixed length into N first fragments; the sender sends the corresponding first fragments to the receiver through the first paths; if M first paths fail in the transmission process of the data frame, the sender splits the data frame into (N-M) second fragments; the sender establishes (N-M) different second paths between the sender and the receiver; and the sender sends the corresponding second fragments to the receiver through the second paths. According to the invention, both secure communication capacity and the self-healing capacity of a military communication network are taken into consideration, and a super-strong military communication network can be constructed.

The invention relates to a short-wave ad hoc network simulation system, in particular to a simulation system for the MIL-STD-188-141B protocol, which belongs to the technical field of military communication. The system is suitable for hierarchical design and modeling simulation of the third-generation automatic link establishment algorithm in the protocol in OPNET simulation software, including four-layer structure: network layer, subnet layer, node layer and process layer. The network module is located at the network layer, including n shortwave ad hoc network platform models located at the subnet layer. The shortwave ad hoc network platform module is located at the subnet layer, including a shortwave network controller module, a shortwave encryption and decryption module, a shortwave modem module and a shortwave transceiver module at the node layer. These modules are designed for the third-generation automatic link establishment algorithm, so they are suitable for simulation before developing a communication system based on the MIL-STD-188-141B protocol. The modular design is also easy to use and upgrade.