256results about How to "Improve combat capability" patented technology

The invention relates to a dynamic game method for multi-unmanned aerial vehicle air battle under uncertain information and belongs to the technical field of aircraft testing and unmanned aerial vehicles. The method comprises the steps of building an unmanned aerial vehicle air battle dynamic game strategy set; building payoff functions of unmanned aerial vehicles of both sides; performing state transition between the functions; calculating a dynamic game Nash equilibrium under interval information; building a system interface and giving a dynamic game combat strategy for multi-unmanned aerial vehicle air battle under uncertain information. The incomplete information dynamic game model method for multi-unmanned aerial vehicle combat can contribute to the development of unmanned combat aerial vehicles of China; being applied to a multi-unmanned aerial vehicle combat platform, the game theory has high theoretical value and practical importance for improvement of ability to survival and combat effectiveness.

The invention discloses a miniature cylindrical launched unmanned plane and a launcher. An unmanned plane is provided with folding wings and in a storage state, the wings are folded below the plane body so that a space utilization rate is high and transport and storage are convenient. The miniature cylindrical launched unmanned plane can be arranged in a launch canister with the corresponding caliber, can be carried conveniently and is suitable for individual equipment. The miniature cylindrical launched unmanned plane can be deployed conveniently and can be immediately used in an individual load state. The miniature cylindrical launched unmanned plane is free of a launch place and a runway, can be used in a plain, an abrupt slope or rough topography such as a mountainous region, has small topography dependence, can be operated simply and can realize one-click launch after communication between the unmanned plane launcher and a ground station.

The invention discloses a multi-unmanned aerial vehicle task decision method based on MADDPG, which introduces an MADDPG algorithm into multi-unmanned aerial vehicle task allocation, and comprises thesteps of firstly establishing a two-dimensional combat environment model required by deep reinforcement learning according to the actual combat environment of multiple unmanned aerial vehicles, secondly establishing mathematical description of various threats such as air defense missiles in the combat environment of the multiple unmanned aerial vehicles, and finally, taking the tracks and distances of the multiple unmanned aerial vehicles and the defense threats of the battlefield as constraint conditions, and performing learning training to obtain a multi-unmanned aerial vehicle task decision model. According to the method, an experience pool and a double-network structure are adopted, so that the operation and convergence speed of the whole network is greatly improved, a result can be obtained more quickly in the high-speed flight process of the unmanned aerial vehicles, the purpose of autonomous decision making of the multiple unmanned aerial vehicles can be achieved, and the highefficiency of task decision making of the unmanned aerial vehicles can also be guaranteed in an unknown combat environment.

The invention relates to a canard forward-sweep telescoping wing aerodynamic configuration with variable span wing area. The canard forward-sweep telescoping wing aerodynamic configuration comprises a fuselage, canards, wings, and a vertical fin; the wings comprise forward-sweep inner wings and forward-sweep telescopic outer wings having internal connections with the forward-sweep inner wings by a telescoping mechanism; and the telescoping mechanism extends to allow the forward-sweep telescopic outer wings to extend to the outside of the forward-sweep inner wings when the mach number (Ma) of an unmanned aerial vehicle is 0.2, and the telescoping mechanism contracts to allow the forward-sweep telescopic outer wings to contract to the inside of the forward-sweep inner wings when the Ma of the unmanned aerial vehicle is 0.4, wherein the area ratio of the forward-sweep telescopic outer wings to the forward-sweep inner wings is 0.25-0.45. The telescoping wing configuration with variable span wing area adopted in the invention allows the unmanned aerial vehicle to have good aerodynamic performances in scopes of different spatial domains and different speeds and the mobility and the flexibility of the unmanned aerial vehicle to be improved. According to the canard forward-sweep telescoping wing aerodynamic configuration of the invention, when Ma is equal to 0.2 or 0.4, the cruise lift-to-drag ratio of the high aspect ratio aerodynamic configuration is over 20% higher than the cruise lift-to-drag ratio of the low aspect ratio aerodynamic configuration when the unmanned aerial vehicle flies at a low speed, and the cruise lift-to-drag ratio of the low aspect ratio aerodynamic configuration is about 15% higher than the cruise lift-to-drag ratio of the high aspect ratio aerodynamic configuration when the unmanned aerial vehicle flies at a high speed, so the capacities of the cruise flight with the Ma of 0.2 and 0.4 are possessed.

The invention discloses a near-distance air combat automatic decision-making method based on single-step prediction matrix gaming. The method comprises the following steps: step 1, erecting a six-degree-of-freedom nonlinear unmanned combat air vehicle control law structure; step 2, initializing a matrix gaming chessboard; step 3, according to the gaming chessboard, carrying out single-step prediction calculation; step 4, calculating a payment function matrix; step 5, carrying out strategy selection through a minimax algorithm; step 6, updating a six-degree-of-freedom plane kinetic and dynamic equation; and step 7, determining whether an air combat termination condition is reached. The method has the following advantages: compared to a three-degree-of-freedom particle model, the actual application value is higher. At the same time, a conventional matrix gaming method based on a maneuver library is changed to be based on a maneuver library of an instruction model, what is needed is only prediction of a step length of a single step, the decision-making time is effectively reduced, the requirement for real-time performance of air verification is satisfied, the method can be better adapted to complex dynamic baffle field environment change, and the combat capability of an unmanned combat air vehicle in a near-distance combat is improved.

An airplane able to change the shape of wing is composed of an airplane body and two wings consisting of fixed wing with one end fixed to airplane body, slide wing installed in the skeleton of said fixed wing and with a roller moving in a spiral slot on a cylindrical body, and the cylindrical body and shape memory alloy bar, which are fixed to each other and installed in the skeleton of said fixed wing. Said shape memory alloy bar is used as the drive source for changing wing shape.

The invention discloses a spatial small aircraft formation flying control system. The spatial small aircraft formation flying control system comprises a task planning system, a formation calculation module, a primary aircraft control module, a formation pattern control module and a secondary aircraft control module, wherein the task planning module is used for sending a mission spatial characteristic and a target characteristic to the formation calculation module; the formation calculation module determines the optimal formation pattern of the spatial small aircrafts and sends the optimal formation pattern to the formation pattern control module; the task planning module is also used for sending a commanded flying state to the primary aircraft directly; the primary aircraft control module performs flying control to obtain a practical motion state; the formation pattern control module calculates to obtain a commanded motion state of a secondary aircraft and sends the calculation result to the secondary aircraft control module; the secondary aircraft control module performs flying control to obtain the practical motion state.

The invention discloses a method and system for controlling hover, reconnaissance and strike integrated aircraft. The control system comprises aircraft, airborne weapon systems, airborne detection systems and a ground monitoring station; belly suspending plates are installed on the aircraft of all states and weapons are installed on the belly suspending plates, electro-optical pods can be installed and the lifting height of the electro-optical pods can be adjusted to prevent the firing of the weapons from being interfered, and other weapons can be suspended outside under wings or on a fuselagewhile the belly suspending plates are installed. According to the designing scheme of the method and system for controlling the hover, reconnaissance and strike integrated aircraft, the problem of limited weapon firing angle is solved, by arranging the belly suspending plates, missiles arranged on the suspending plates are capable of keeping in the same pointing direction with an observing and sighting device at any time, but synchronously alignment is not necessary, the missiles only need to be capable of keeping in the same pointing direction with the observing and sighting device at any time, or capable of pointing at the same direction along with the observing and sighting device, and therefore firing conditions can be set up at any time to overcome defects in the prior art.

The invention relates to a six-degree-of-freedom unmanned combat aerial vehicle short-range dogfight method based on a simplified model machine game. The method comprises the steps that 1, a six-degree-of-freedom non-linear unmanned combat aerial vehicle Simulink model is established; 2, a six-degree-of-freedom non-linear unmanned combat aerial vehicle control law is designed; 3, an unmanned combat aerial vehicle simplified model is established; 4, an airborne cannon model is established; 5, an unmanned combat aerial vehicle control input instruction library is designed; 6, input instruction switching is controlled; 7, an unmanned combat aerial vehicle short-range dogfight machine game model based on the simplified model is established; S8, simulation verification is conducted. The method aims at providing an unmanned combat aerial vehicle aerial warfare autonomous decision-making method which has actual application value, the decision accuracy and scientificity are guaranteed, and meanwhile the decision time is effectively shortened, so that the fight power of an unmanned combat aerial vehicle is improved.

The invention discloses an intelligent control system and an intelligent control method for a fire engine, which belong to the technical field of fire protection and automatic control. The system comprises a master controller, buses, a touch displaying screen, a water pump inlet pressure sensor, a water pump outlet pressure sensor and an air cylinder pressure sensor. The master controller receives input signals of the sensors and receives signals sent by an engine water temperature induction plug and an engine oil pressure induction plug. The master controller is in bidirectional connection with a water pump speed sensor, a water tank liquid level meter, a concentrated tank liquid level meter, a voice promoting device and an engine electronic control unit (ECU) through the buses. The master controller transmits output signals to a scramming device, a rear water inlet valve, an internal water injection valve, an electronic accelerator, a water diversion pump control device and a coupled pump control device. The control method has three modes of water tank fire extinction, water diversion fire extinction and water tank water injection. By means of the intelligent control system and the intelligent control method for the fire engine, fire extinction operation of the fire engine achieves intelligent control, human errors are avoided, single-person fighting ability is improved, fire extinction efficiency is improved, and a maintenance period and service life of the fire engine are prolonged.

The invention provides an intelligent material driven or mechanical driven aircraft with turnable wings, and the aircraft provided by the invention has the advantages of high speed, long voyage, low oil consumption, capability of VTOL (vertical take-of and landing), and capability of hovering. The aircraft comprises an aircraft body, sectional bending turnable wings, electroactive polymer skins, sheet macro-fiber piezoelectric composite material bars, deformed honeycomb fillers, a reversal platform and variable pitch propeller engines, wherein the two variable pitch propeller engines are symmetrically mounted on the rear edges of the wings, the electroactive polymer skins are taken as wing skins, the sheet macro-fiber piezoelectric composite material bars are arranged on the neutral layers of the wings, the spaces between the wing skins and the sheet macro-fiber piezoelectric composite material bars are filled with the deformed honeycomb fillers, and the reversal platform is placed ata rotary center inside the aircraft body. According to the invention, an intelligent driver is utilized as the driving source for wing turning, and the aircraft has the advantages of light weight, simple mechanism, high efficiency and convenience for maintenance, and can be switched rapidly in flying modes of level flaying and hovering through wing turning.

The invention relates to a fire-fighting early-warning monitoring and intelligent management system based on an internet. The system integrates functions of eight kinds of software, comprising telephone networking early-warning software, wire video monitoring early-warning software, wireless video monitoring early-warning software, mobile video monitoring early-warning software, satellite video monitoring early-warning software, video on demand software, video session software, live video software, and the like, and the functions can be used independently or integratedly by users. The system can perform large-area networking management on fire alarm systems in buildings, and can realize effective monitoring and quick alarm. The system guarantees the normal operation of the fire alarm systems and fire safety facilities, improves the reliability of the fire alarm systems, and reduces the rate of false alarm. Moreover, through the equipment operating data and alarm information of the fire early-warning monitoring intelligent alarm system based on the internet, the developing process of intelligence and networking of city fire management is accelerated, and thus, the integral technology level and the comprehensive capability of fire prevention and reduction are enhanced.

The invention belongs to the field of aircraft structural dynamics, and relates to a method for analyzing influences of wing deformation and vibration on aircraft transfer alignment. The method is characterized by including the following steps: (1) building a full-aircraft structure dynamical model, (2) building a full-aircraft unsteady aerodynamic model, (3) building a transfer relationship between plug-ins and inertial navigation, and (4) obtaining a primary-secondary inertial navigation error fitting empirical formula. The method has the advantages that speed errors and angular speed errors generated between the primary inertial navigation and the secondary inertial navigation of an aerial movable platform are analyzed through the built aircraft structure dynamical model, then the errors are eliminated through filtering, and in this way, the transfer alignment time of the primary inertial navigation and the secondary inertial navigation during guided missile launching can be shortened to a great degree.

The invention relates to a multi-aircraft flight path planning method based on a deep Q learning algorithm. The method comprises the following steps: S1, constructing a kinematic model of an aircraftbased on the performance of the aircraft; S2, constructing a task model of the aircraft based on a deep Q learning algorithm according to a to-be-hit target; S3, constructing a state space of the aircraft according to the kinematics model and the task model; S4, constructing an action space of the aircraft according to the kinematics model and the task model; S5, constructing a neural network anda reward function based on the deep Q learning algorithm based on the state space and the action space; S6, training the neural network based on the reward function; and S7, performing target strike verification on the trained neural network. And multi-aircraft cooperative flight path planning is completed through a deep Q learning algorithm, and target strike under the constraints of minimum energy loss, shortest strike time, air defense threat area avoidance and the like is realized.

The invention discloses an infrared ray and ultrasonic wave mixed sighting device and belongs to the technical field of tactic reconnaissance equipment. The infrared ray and ultrasonic wave mixed sighting device comprises a controller (1), an alarming module (2), a power source module (3), an ultrasonic distance-measuring module (4) and an infrared sensing module (5), wherein the controller (1) is respectively and electrically connected with the ultrasonic distance-measuring module (4), the infrared sensing module (5) and the alarming module (2), and the power source module (3) provides electric energy for the controller (1), the ultrasonic distance-measuring module (4), the infrared sensing module (5) and the alarming module (2). Compared with the prior art, the infrared ray and ultrasonic wave mixed sighting device has the advantages of being simple in structure, reliable in performance, high in stability, high in operational effectiveness and the like.

The invention provides a resource pool-based coordinated detection system resource scheduling method of a phased array radar. In a multifunctional phased array radar coordination system, system resources for target detection, coordinated networking and information transmission are uniformly dispatched and distributed, so that not only can the guarantee of the resource cost of a radar detection function be considered, and also the system resources for a coordinated detection function system are also considered. The physical resources of various nodes of the coordinated detection system are virtually described and packaged to form a coordinated detection system resource pool, the barrier of the physical node resources is broken, and the unified management and control of the resources of the coordinated detection system are achieved. Randomized search genetic algorithms of natural selection and genetic mechanisms of the biosphere are adopted, and the total detection income of the task is taken as an optimized objective function and the total amount of various resources in a resource pool is taken as a constraint condition for optimization, so that the optimal distribution of the system resources is achieved.

The invention discloses a pump water spray propulsion double-hydrofoil shallow diving carrier, which is technically characterized by absorbing the superiorities of a submarine, a carrier, a modern small water plane catamaran with superhigh speed and a hovercraft, and by using 'a multilevel double-circular-arc-gear high pressure pump with large flow rate', 'a multilevel internal series double supercharged and double-circular-arc-gear pump' as a water spraying pump and an air-cushion pump of a ship and by adopting the structure of a shallow diving carrier which uses a multi-functional double hydrofoils submerged body to provide buoyancy and dynamic forces. The ship body carries power and pump spraying water, which transports the high pressure and large flow rate water to a direction-adjustable spray head which is positioned on the tail part of the multi-functional double hydrofoils submerged body under the ship body, so as to achieve the water spray propulsion. Besides providing the buoyancy and dynamic forces, the double hydrofoils submerged body also has the functions of oil storage, inputting water in a respective cavity and controlling the shallow diving and the ship attitude, and is also provided with overall strength, thus forming a small water plane catamaran structure; the double hydrofoils submerged body is also provided with an air-cushion. When the submerged body uses the pump to exhaust water, the ship body surfaces, and likes a small water plane catamaran, the spray head can spray water and is promoted in water when avoiding the water resistance to go forward at high speed; the carrier is a propeller-typed ship and can not realize a sea skimming flight, which is the most superiority in the water spray propulsion.

The invention discloses a co-aperture infrared / radar composite seeker and belongs to the radar infrared composite detection device technical field. The common aperture infrared / radar composite seeker includes an infrared thermal imager, a radar detection module, a pitching frame, a main support, a mounting plate, a driving motor, azimuth motors, a driving gear and a driven gear; after being fixedly connected with the radar of the radar detection module through a screw in a co-aperture manner, the infrared thermal imager is fixed onto the top of the pitching frame through the mounting plate; the two azimuth motors are installed at the middle of the pitching frame; the pitching frame is installed between two supporting plates of the main support through a connection shaft and a bearing; the driving motor is fixed onto the outer side surface of the supporting plate of the main support; the driving gear is located at the inner side surface of the supporting plate of the main support, and is fixedly connected with the output shaft of the driving motor; and the driven gear is fixed to the bottom of the pitching frame and is engaged with the driving gear. The co-aperture infrared / radar composite seeker of the invention has the advantages of miniaturization and light weight, and is conductive to the improvement of combat capability.

The invention relates to a high-speed and heavy-duty rubber belt-type track section and a track made by track sections for the purpose of solving the problem that a conventional rubber belt-type track fails to achieve light weight. One track section comprises a traction framework and a support framework. The support framework is formed in such a manner that multiple unit bodies are intermittently arrayed. The traction framework is composed of track pins at two ends, two segments of steel wire tire cords entwining between two ends of the track pins and aramid cords disposed outside of the steel wire tire cords. The two segments of steel wire tires enable the track pins to be divided into three segments. A unit body of each support framework is composed of an upper part and a lower part. Upper parts and lower parts are integrally formed by high polymer material disposed outside and metal disposed inside. Unit bodies of support frameworks, the steel wire tire cords and the aramid cords and portions which the track pins entwine the steel wire tire cords are vulcanized integrally. The track made by the high-speed and heavy-duty rubber belt-type track sections is formed by connection of a middle coupling device and end coupling devices. The high-speed and heavy-duty rubber belt-type track section and the track made by track sections have following beneficial effects: weight of the track is decreased; operation efficiency and service lifetime of the track are increased and prolonged; and survival ability and action performance of an armored vehicle are enhanced.

The invention discloses an improved PMADDPG multi-unmanned aerial vehicle task decision-making method based on transfer learning. The method comprises the steps of firstly, performing reasonable mathematical modeling for threats such as air defense missiles and radars in an environment under the background of a multi-unmanned aerial vehicle actual combat environment, then creating a plurality of different two-dimensional combat environment models, designing constraint conditions, and learning and training the plurality of combat environments in sequence, thereby obtaining a final multi-unmanned aerial vehicle task allocation model. According to the method, the defect that in the prior art, task decision making can only be carried out in a known or static combat environment is overcome, decision making can also be carried out efficiently in an unknown combat environment, tasks of unmanned aerial vehicles are achieved, and the viability of an unmanned aerial vehicle group in the unknowncombat environment is greatly guaranteed.

The invention provides a high overload ablation resistant EPDM (Ethylene-Propylene-Diene Monomer) elastic heat insulation material which is prepared from 100 of EPDM, 15 to 20 of aromatic polyamide organic fiber, 5 to 12 of inorganic fiber, 12 to 25 of a silicon dioxide strengthening agent, 3 to 5 of zinc oxide, 5 to 15 of a petroleum based softener, 5 to 20 of an ammonium salt flame retardant, 10 to 30 of deca-brominated diphenyl ether, 5 to 15 of antimonous oxide and 2 to 4 of a peroxide vulcanizing agent, wherein the aromatic polyamide organic fiber is aramid fiber or heterocyclic aramid fiber; the inorganic fiber is asbestos fiber or ceramic fiber; the petroleum based softener is one of liquid paraffin and naphthenic oil. The high overload ablation resistant EPDM elastic heat insulation material is excellent in overload ablation resistance and relatively high in mechanical property and processing property, is applicable to the requirement of a high overload engine for the erosion resistance of an inner heat insulation material; therefore, effective heat insulation is guaranteed, the thickness of a heat insulation layer can be reduced, and the packing factor of the engine is increased.

The invention discloses a compressed nitrogen and foam fire-extinguishing system. The compressed nitrogen and foam fire-extinguishing system comprises a fire-extinguishing foam tanker and a nitrogen tanker, wherein the fire-extinguishing foam tanker is basically equal to a fire-extinguishing foam tanker in the prior art, the nitrogen tanker is provided with a compressed nitrogen system, the nitrogen system comprises a nitrogen generating device and a nitrogen delivery pipeline, and the nitrogen outlet end of the nitrogen generating device is connected with a water-foam mixing pipeline on the fire-extinguishing foam tanker to form a compressed nitrogen and foam liquid pipeline. The compressed nitrogen and foam fire-extinguishing system has the technical advantages that oxygen supported combustion in the air is completely eradicated, a foam insulation effect is improved, and the fire disaster suppressing capability is strengthened. The nitrogen generating device serves as an independent unit to constantly supply nitrogen, accordingly the operating capability of the whole fire-extinguishing system is improved, and the fire-extinguishing system is especially suitable for large fire disaster handling.

The invention discloses an airborne opportunistic array radar target searching algorithm based on search resource management. The airborne opportunistic array radar target searching algorithm comprises the steps of: firstly, discussing important search parameters, determining priority of each subregion according to priori knowledge, determining average power pavi, beam width theta i and beam residence time tdi of an airborne opportunistic array radar in the i-th subregion as optimization parameters, constructing a signal-to-noise ratio Snri, introducing credibility, and calculating beam position digits Ni and search frame periods Tfpi of different threat level regions; secondly, calculating detection probabilities pdi, and establishing a radio frequency stealth constraint planning model under an uncertain condition of a target threat environment by taking the minimized radiation energy and the maximum detection probability as target functions; and finally, solving the model by adoptingan improved genetic algorithm. The optimized radar target searching algorithm is designed by the invention, has good detection performance, and improves the radio frequency stealth performance of theairborne opportunistic array radar.

The invention relates to an intelligent human platform establishing method for equipment design and evaluation. The method comprise the steps of 1) building a real three-dimensional digital soldier parameterized model, and controlling the human body height, weight and percentile; 2) performing individual movement simulation; 3) performing individual equipment parametric modeling and building a model base; 4) performing geometrical efficiency evaluation, biomechanical analysis evaluation, load metabolism analysis evaluation and comprehensive operational effectiveness fuzzy evaluation on single soldiers on the basis of prior standards, calculation models and independent experiment data. The main objective of the human platform is to develop individual equipment and soldier system ergonomic characteristics fully, study relations of soldiers, equipment and battlefield environments and how to design and improve the relations so as to achieve the reasonable combination, and accordingly, the developed equipment can be suitable for solider physiological and psychological characteristics, and the individual comprehensive operational effectiveness and survivability can be improved. The method can be widely applied to individual training.

The invention provides a terminal for detecting and diagnosing atmospheric duct in real time. The independent terminal is connected onto a radar on active duty and has the capability for detecting and diagnosing the atmospheric duct on the premise that the work and the performance of a shore based radar or a ship-based connected radar are not influenced. The terminal comprises a work station (or a server) based on a compact peripheral component Interconnect (CPCI) bus, an interface module, a medium-frequency sampling digital receiver, a high-speed digital signal processor and an integrator formed by related software. The terminal acquires echoes and data by utilizing the connected radar, performs isolation and amplification through the interface module, then sends an original signal to the medium-frequency sampling digital receiver and the high-speed digital signal processor to be processed and converted so as to obtain sea clutter data, measures and calculates sea clutter power, performs atmospheric duct parameter inversion through atmospheric duct detecting and diagnosing software, and finally displays atmospheric duct parameters on a displayer of a control console. The terminal fully utilizes existing functions of the connected radar, does not influences normal usage, and is low in modification cost, convenient to install, high in reliability and suitable for radars with X wave bands, C wave bands and S wave bands.

The invention provides an invisibility high-maneuvering target drone and a control method of the invisibility high-maneuvering target drone, and relates to the technical field of unmanned aerial vehicles. The technical problem that in the prior art, the target drone invisibility characteristic is poor, and the comprehensive matching degree of target drone invisibility design and flying performanceis poor is solved. The invisibility high-maneuvering target drone comprises an aircraft body, a wing, a vertical tail, a horizontal tail and a clam type air inlet way arranged below a belly of the aircraft body, the wing is arranged in the middle of the aircraft body and is arranged in lower single-wing layout, and the vertical tail and the horizontal tail are arranged on the tail of the aircraftbody. According to the control method of the invisibility high-maneuvering target drone, the high-accuracy high-confidence-coefficient dynamical model is affirmed, through overload and posture combined control, large-overload stable control flying is ensured, and a control system uses overload, speed, the attack angle and the side sliding angle. The problem that an existing target drone is poor in invisibility characteristic is solved, and the problem that the matching degree of target drone invisibility design and flying performance is poor is solved.

A fire protection wireless multi-channel on-site commanding network communication platform comprises a data exchanging management server, a user dispatch server, a multi-channel relay base station used for a fire protection force extinguishment rescuing site and a special communication terminal. The data exchanging management server is used for data exchanging and processing. The user dispatch server is used for monitoring the states of the multi-channel relay base station and the site special communication terminal and achieves a communication managing function. The multi-channel relay base station is used for covering site communication signals and achieves data receiving, sending and dynamic route calculating functions. The site special communication terminal is used for achieving site combatant point-to-point and point-to-multi-point wireless audio and video and data transmission communication. The platform has good emergency characters, the multi-channel relay base station is provided with three data output channels, and the frequency points of the channels can be set by the channels. The multi-channel relay base station can automatically calculate wireless communication routes, dynamic bridging between a fire protection satellite communication network and other site emergency networks is achieved, and network crossing application is achieved.

The invention provides novel fragment-resistant sandwich-structure aramid composite cloth, and relates to the field of individual protection. The fragment-resistant sandwich-structure aramid composite cloth is formed by two layers of no-woven cloth or unidirectional fiber prepreg and one layer of woven cloth in a compositing mode, and the layers adhere together through an adhesive. The surface density of the single-layer no-woven cloth is 210 g / m<2>+ / -5 g / m<2>, the surface density of the unidirectional fiber prepreg is 105 g / m<2>+ / -5 g / m<2>, and the surface density of the woven cloth is 200 g / m<2>+ / -5 g / m<2>. The surface density of each layer of sandwich-structure aramid composite cloth pattern is 620 g / m<2>+ / -15 g / m<2> or 410 g / m<2>+ / -15 g / m<2>. The invention further provides a preparation method of the fragment-resistant sandwich-structure aramid composite cloth. A bulletproof and stab-resistant clothes product prepared from the sandwich-structure aramid composite cloth has both functionality and comfort, is excellent in stab residence and fragment resistance, is high in wearing comfort due to the good material flexibility and can obviously improve the combat efficiency of combat staff.

The invention discloses a second generation Beidou satellite time service watch, which belongs to the time service technology of the watch and mainly solves the error problem of the existing watch. The second generation Beidou satellite time service watch comprises a watch chip, a pointer arranged on the watch chip, a power supply source connected with the watch chip, and a second generation Beidou satellite signal reception antenna connected with the watch chip, wherein the second generation Beidou satellite chip module is further connected with the power supply source. The invention further provides an implementation method of the watch; the high-precision time service function of the Beidou satellite is applied to the watch so that an ordinary watch also has high-precision time service function; therefore, the practicability of ordinary watch is greatly improved.