146results about How to "Large communication capacity" patented technology

A MIMO communication system having deterministic channels wherein MIMO is applied to line-of-sight channels having a fixed geometrical positional relationship so as to increase the channel capacity. A line-of-sight MIMO communication system having a plurality of channels includes a channel matrix calculation processing section on a transmission or reception side or both of the transmission and reception sides. The channel matrix calculation processing section updates an orthogonal channel formation matrix in accordance with a fluctuation of a transmission antenna position or reception antenna position or a fluctuation of the channels.

Radio base station apparatus 100 of the present invention monitors total transmission power which is the sum of transmission power for all mobile station terminals 200-203 connected for communication, reduces the upper limit of transmission power for the lowest prioritized mobile station terminal by a predetermined amount when the total transmission power exceeds a first threshold which is referenced to determine whether or not the transmission power has been reduced, and terminates communication with the lowest prioritized mobile station terminal when the total transmission power exceeds a second threshold which is larger than the first threshold.

The invention discloses a WG radio transceiver, comprising a mobile communication module, a communication module of WiFi wireless LAN, a data host, an antenna, a data wire and a driver power source, which implements the technical proposal for monitoring house state in a short distance through smart phones which rely on a WiFi wireless LAN and monitoring house state in a long distance through smart phones which rely on a mobile communication network, and the invention is characterized by real-time and bidirectional information exchange, large communication capacity, good compatibility, strong capacity for resisting disturbance and convenient switch between short-distance control and long-distance control, thus being an ideal smart household controller.

The invention discloses a reflection array antenna for a co-frequency co-time full duplex system (CCFD). The system can receive and emit signals which have the same working efficiency and are polarized in the same direction. The system comprises an emitting end feed source, a receiving end feed source and a reflection array. The emitting end feed source and the receiving end feed source are arranged on the same side of the reflection array in a side feeding mode and are in mirror symmetry about the reflection array. The reflection array is formed by double-layer metal patch units, and the sizes of upper metal patches of the each double-layer metal patch unit are smaller than those of corresponding lower metal patches. The sizes of the patches of the patch units in the reflection array are adjusted to conduct phase compensation on the corresponding patch units, so that a pencil beam in the array face normal direction is formed after the reflection array is illuminated by the emitting end feed source, and the receiving end feed source receives an incoming wave signal in the array face normal direction. Meanwhile, high enough isolation is provided between the receiving feed source and the emitting feed source so as to ensure the good electromagnetic compatibility of the system.

The invention discloses a 1.2m feedback full-automatic portable emergency satellite communication antenna servo system which comprises a portable box, an antenna structure unit and an antenna control unit, wherein the antenna structure unit and the antenna control unit are arranged in the portable box; the antenna structure unit comprises an antenna mount, a six-section carbon fiber antenna main reflection surface and a feed source component support frame, wherein the six-section carbon fiber antenna main reflection surface and the feed source component support frame are connected to the antenna mount, an antenna auxiliary reflection surface is installed at the end part of the feed source component support frame, a feed source component support plate is installed in the middle of the feed source component support frame, a feed source component is installed on the feed source component support plate, a direction drive device and an elevation drive device are arranged in the antenna mount, and the feed source component comprises a feed horn, a polarizer, a duplexer and a polarization power transmission mechanism. The 1.2m feedback full-automatic portable emergency satellite communication antenna servo system is reasonable in design, convenient in implementation, increased in communication bandwidth, expanded in communication capacity, high in degree of intelligence and working reliability, convenient to carry and good in use effect, provides communication guarantee for the emergency handling and is convenient to popularize and apply.

The invention discloses a three-frequency dual polarization cone conformal micro-strip antenna array. Three-frequency operation is achieved by vertically placing a single-frequency micro-strip antenna array and a dual-frequency micro-strip antenna array on the surface of a cone, and the antenna arrays evenly surround the surface of the cone to achieve omni-directional wave beam coverage. Each array is formed by connecting four micro-strip antenna units through micro-strip lines in a parallel feeding mode. Micro-strip antenna radial edges feed a single-frequency antenna unit, and micro-strip antenna non-radial edges feed a dual-frequency antenna unit. The size of patches is reduced by slotting the non-radial edges of the single-frequency antenna unit, and a patch unit works for linear polarization. Dual frequency is achieved by slotting the radial edges of the dual-frequency antenna unit, low frequency is circular polarization, and high frequency is linear polarization. Micro-strip media used for processing antennas are flexible special media. According to the three-frequency dual polarization cone conformal micro-strip antenna array, the three-frequency dual polarization work requirement can be achieved on the surfaces of limited carriers, and omni-directional coverage of wave beams can be achieved.

The invention discloses a a space-borne switchboard with distributed mixing implementation structure and an implementation method thereof. In the implementation method, signals of hundreds of wave beams sent from a receiving digital beam forming (DBF) network are sent to a corresponding uplink processors by a receiving-circuit waveform exchange module first so as to realize the selection and processing of a channel; and after base band exchange and spread spectrum modulation are performed, the convergence of the signals of the wave beams is realized by an emitting-circuit waveform exchange module. The implement method comprises the steps that: a, the receiving-circuit waveform exchange module sends M arbitrary signals of the wave beams to N1 uplink processors under control commands according to the mapping relationship; b, after carrying out de-spreading modulation on the signals, the uplink processors complete the combination of channel associated signaling by a base band exchange module and the exchange output to N2 downlink processors; and c, the emitting-circuit waveform exchange module outputs the outputs of the downlink processors to the receiving digital beam forming (DBF) network in the form of the wave beam. The distributed mixing implementation structure for the space-borne switchboard and the implementation method thereof of the invention can meet the requirements for scheduling capability produced in space-borne processing services when different wave beams of a user service subjected to space-borne processing are distributed non-uniformly and the distribution is changed dynamically with time so as to meet the requirements for user processing with minimum space-borne processing resources.

The invention relates to a visible light communication system and method based on probabilistic shaping coding, and application equipment, and relates to the field of light communication systems. Bitsof input data are grouped at a sending end, and mapped into new bits according to the set probability; then, forward error correction coding is carried out; the coded data forms an OFDM frame; then,a data flow is formed and sent; and a receiving end receives the data flow from the sending end, recovers the OFDM frame, performs inverse mapping on the decoded data after performing OFDM frame decoding and forward error correction decoding, and recovers the original data bits by using a probability mapping rule corresponding to the sending end. Due to addition of probability mapping, the net information rate of the system can be adjusted; the communication capability of the system can be increased; adjustment is carried out flexibly; and furthermore, the complexity is relatively low.

The invention discloses a latent communication system and method based on a non-cooperative blind source. The latent communication system comprises an information coding and transmitting end, an information receiving and demodulating end and a non-cooperative blind source signal, a non-cooperative blind source is used as a communication carrier wave, double antennas or multiple antennas are used as receiving ends, received electromagnetic waves are demodulated in a receiver, and therefore hidden transmission and passive transmission communication of information are achieved. By adopting the technical scheme of the invention, a signal emission source is not needed, the carrier emission power is saved, and new spectrum resources are not occupied; the circuit structure is simplified, and thehardware cost is reduced; concealed communication is guaranteed in the physical level, and indoor directional fixed-point communication can be achieved. Information can be sent to a sensor at a specific position in the Internet of Things, energy is provided for the radio frequency identification tag, and the wireless communication quality is improved.

In a MIMO wireless communication system, the transformation process synthesizes the eigenmodes having a large singular value (i.e. a high effective SNR) and the eigenmodes having a small singular value (i.e. a low effective SNR). Thereby, the former eigenmodes are converted into modes having suppressed effective SNR which do not require a large number of levels of modulation, and the latter eigenmodes are converted into modes having increased effective SNR instead. In a MIMO wireless communication system for eigenmode transmission, a large communication capacity is realized without increasing the number of levels of modulation even in a communication environment capable of achieving a high SNR.

The invention provides a highway safety access device with real-time communication and safety protection functions. The highway safety access device comprises a highway safety access card, an on-board unit (OBU) matched with the highway safety access card and a road side unit (RSU) communicated with the OBU. The safety access card is placed in the OBU, communication is carried out by using the dedicated short-range communication (DSRC) technology, and travelling information needing to be paid attention to is told to a driver in real time. In particular, by means of data interaction and operation, accident chains are blocked, and serial harm caused by highway vehicle accidents is reduced to the minimum. According to the highway safety access device, the highway safety access card is locked in the OBU in the whole process, so that vehicles are prevented from evading highway tolls; DSCR is adopted, so communication quality can be guaranteed under bad weather conditions; meanwhile, a DSRC module has an encryption function, and communication safety can be guaranteed.

The invention discloses high-speed omni-directional wireless laser communication equipment. The equipment mainly comprises a shell, wherein, the shell is internally equipped with an MCU (micro control unit) modular circuit, a wireless encoding-decoding and modulation-demodulation modular circuit, an operational amplifier modular circuit, a filter modular circuit, an omni-directional optical antenna modular circuit, a signal processing modular circuit, a control signal interface circuit and a power supply modular circuit; and an omni-directional optical antenna, a communication interface, a control signal interface and a power interface are arranged on the shell. By utilizing the high-speed omni-directional wireless laser communication equipment, certain mobile communication equipment, terminals and electronic equipment in an aircraft and a cabin can be interlinked together so as to realize high-speed omni-directional simultaneous two-way transmission of data signals such as a speech signal, an image signal, a network signal and the like; and trivial cabling is avoided, and weight and power consumption of a system are reduced.

The invention discloses a free space laser communication system based on quantum encryption. The system comprises a receiving module and a data decryption module, wherein the receiving module capturesa laser signal and a communication request signal, amplifies, processes and quantizes the laser signal through broadband amplification and pulse code modulation, codes the laser signal and then converts the laser signal into a digital signal. A computer module processes data, and then records communication node information and freely organizes a communication network according to a communicationrequest and transmits data to a data encryption module; a quantum key terminal obtains a quantum key, the data encryption module encrypts the data, and the encrypted data is transmitted to a counter party of communication through a transmitting module. A receiving party communication node obtains the quantum key through the quantum key terminal and decrypts the received data through the data decryption module, and further transmits the decrypted data to the computer module for processing. For the system provided by the invention, fixing communication nodes or paving electric cables/optical cables is not needed, and the system can perform long-distance transmission and avoid obstacles and bad weather regions.

The invention relates to physical layer encryption in the technical field of wireless communication safety, and in particular relates to a method and device for encrypting MMSE (minimum mean square error) pre-equalization wireless channel based on multipath redundancy. In the method, under a TDD (time division duplex) working pattern, 1) firstly, a receiver sends channel detection signals by utilizing an upstream channel, wherein the channel detection signals are used for detecting a multipath channel; 2) the receiver estimates wireless channel multipath information between the receiver and atransmitter according the received channel detection signals sent by the upstream channel; 3) the wireless channel multipath information is subjected to turnover treatment; 4) a pre-equalization factor is obtained on the basis of a power constraint condition according to the wireless channel multipath information; and 5) signals to be sent are pretreated by utilizing a pre-equalization factor anda pre-treatment factor. According to the invention, based on the multipath redundant property of the wireless channel and time diversity concept, the environment adaptivity is introduced in a wireless wide band communication system by utilizing a time-reversal technology, the channel is encrypted by utilizing time reversal, and the safety issue brought by broadcast property of the wireless channel is solved.

The invention discloses an array waveguide grating module with polarization control. An input waveguide is connected with an input end of a polarization beam splitting-rotator, two output ends of the input waveguide and the polarization beam splitting-rotator are respectively connected with respective a first slab waveguide and a second slab waveguide through a first connecting waveguide and a second connecting waveguide, a group of array waveguides are connected between the first slab waveguide and the second slab waveguide, one end of each output waveguide of a first output waveguide group is an output port, the other end of each output waveguide of the first output waveguide group is connected with the first slab waveguide and is positioned on the same side of the first connecting waveguide, one end of each output waveguide of a second output waveguide group is an output port, and the other end of each output waveguide of the second output waveguide group is connected with the second slab waveguide and is positioned on the same side of the second connecting waveguide. Only the standard process of array waveguide grating manufacturing is needed, the array waveguide grating module with the polarization control can be used as a polarization insensitive receiving module in a wavelength division multiplexing system, or as a receiving and transmitting module in a wavelength division multiplexing-polarization multiplexing mixing multiplexing system.

The invention discloses an asynchronous digital communication system and method jointly modulating frequencies and amplitudes of multiple sub-bands. The method is as follows: dividing the band width of a communication channel into a sub-band or multiple sub-bands; and carrying out jointly asynchronous relative modulation of frequency and amplitude on each sub-band. The system comprises a transmitter and a receiver, multiple code element decision units of the transmitter are respectively connected with multiple input ends of a transmission and calculation control unit; multiple carrier generation units are connected between multiple output ends of the transmission and calculation control unit and the input ends of multiple wireless transmission units; frequency and amplitude storage units are respectively connected with the input ends of the multiple carrier generation units and the transmission and calculation control unit; and frequency and amplitude decision units are respectively connected with the frequency and amplitude storage units and the multiple input ends of the transmission and calculation control unit. In the invention, a direct digital frequency synthesis technology and a high-precision frequency estimation technology are combined through hardware, thereby taking full advantages of the technologies to realize high-reliable communication resisting Doppler frequency deviation and long time delay.

The invention discloses a short-range wireless information transmission method and a mobile terminal, and relates to the technical field of wireless communication. The problem that the data rate, confidentiality and the effective communication distance cannot be all considered in the prior art is solved. The method comprises the following steps: a present side mobile terminal converts to-be-sent data into a digital signal and a modulating signal through a processor and a modem in sequence, and then a laser generates a laser signal according to the modulating signal and emits the laser signal; an opposite side mobile terminal receives the laser signal through an optical receiving antenna, a photoelectric converter converts the laser signal into an electric signal, the modem demodulates the electric signal, and finally the processor restores the data sent by the present side mobile terminal according to a demodulating signal. The method disclosed by the invention is applied to the mobile terminal.

The invention provides a method for improving the performance of a wireless optical communication system. The method comprises the following steps: establishing a transmitting end and a receiving endof a communication system, transmitting a plurality of groups of vortex light beams with different initial beam waist radiuses from the transmitting end to the receiving end, establishing a vortex beam orbital angular momentum model, obtaining a receiving probability transmitted from the transmitting end to the receiving end, establishing a change curve graph of the receiving probability changingalong with initial girdle radius, and taking the initial beam waist radius corresponding to the maximum value of the receiving probability in the change curve graph as the initial beam waist radius ofa transmitting beam of the communication system. Appropriate light beam parameters can be selected according to practical application, interference of the transmission distance on wireless optical communication is effectively reduced, the light beam parameters are reasonably and correctly selected, and the performance of the wireless optical communication is improved.

The invention discloses a hybrid modulation and demodulation method for atmospheric laser communication. Multi-pulse pulse position modulation and high-order polarization shift keying modulation are mixed together, a Stokes parameter is extracted for a polarization state of the light during the demodulation, the polarization state is almost constant after atmospheric transmission, the three-dimensional demodulation of the Stokes parameter has a larger coding space and decision space compared with the one-dimensional demodulation or two-dimensional demodulation, therefore the anti-interferenceperformance is high, moreover, the coding space and the decision space are expanded by using the three-dimensional demodulation, so that the PolSK can be pushed to multi-order use on the premise of ensuring the bit error rate performance; whether a time slot receiving signal is an additive white gaussian noise signal is judged by using the extracted Stokes parameter at a receiving end, so that whether a pulse is received within the time slot can be judged, and the demodulation of the pulse position is finally achieved; and by adoption of the method, the use of the signal amplitude demodulationposition in the traditional method is avoided, the demodulation process is simplified, and the demodulation efficiency is also improved.

The invention discloses a terahertz OAM (Orbital Angular Momentum) generation system based on an optical mixing and fusion optical communication system. The terahertz OAM generation system includes two DFB (Distributed Feedback) lasers of which the frequency difference is in the terahertz band and which are used for generating optical communication wavelengths, a spatial light modulator which is used for modulating the orbital angular momentum of one channel of optical communication wavelength, a Mach-Zehnder modulator which is used for modulating the baseband electrical signal information ofthe other channel of optical communication wavelength, and a terahertz photoconductive antenna mixer which is used for beating the frequency of the combined optical signal to generate the terahertz band communication carriers of a modulated baseband signal carrying a certain order of orbital angular momentum. The frequency difference and phase difference transfer effects of the terahertz photoconductive antenna mixer are utilized to modulate the orbital angular momentum of one channel and the baseband electrical signal of the other channel without adding devices other than optical communication. The terahertz OAM generation system can be integrated with the current large-capacity optical communication system. By utilizing the frequency and phase transfer effects of photon mixing, the technical problems of OAM generation and channel multiplexing in the terahertz band can be solved.

The invention provides a base station antenna with a same-frequency mutual coupling effect reducing device, which comprises a metal base, an outer cover, a plurality of columns of antenna units and decoupling devices, and is characterized in that the decoupling devices are arranged between two adjacent columns of antenna units; the frequencies of the multiple columns of antenna units are the same, and the distance S between every two adjacent columns of antenna units is smaller than 1/4 of the center frequency wavelength of the antenna units and larger than 1/10 of the center frequency wavelength of the antenna units; the length L of the decoupling device is greater than the length of the antenna unit, the height H is equal to the height of the antenna unit, and the width D is greater than 1/16 of the central frequency wavelength of the antenna unit. The base station can be provided with more antennas by reducing the distance between the multiple columns of antenna units so as to enlarge the communication capacity of the base station, and the decoupling device is arranged between the two adjacent columns of antenna units so as to reduce the mutual coupling effect between the adjacent antenna units, so that the mutual coupling effect between the antenna units is effectively reduced under the condition that the design size of the base station antenna is met.

The invention relates to an audio-video monitor system based on optical fiber transmission. The audio-video monitor system comprises a front end camera, a pickup, an optical fiber transmission module, a digital video recorder and a displayer. The front end camera and the pickup are respectively connected with input ends of the optical fiber transmission module; output ends of the optical fiber transmission module are connected with the digital video recorder and the displayer; audio signals and video signals collected by the front end camera and the pickup are transmitted to the digital video recorder and the displayer through the optical fiber transmission module; the digital video recorder stores the received signals; and the displayer displays the received signals in real time. Compared with the prior art, the audio-video monitor system has the advantages of large message capacity, long transmission distance, strong anti-electromagnetic interference ability, good safety and so on.