187results about How to "Realize demodulation" patented technology

The invention provides a simplified multiplexing white light interference fiber sensing demodulating device, which comprises a single-fiber two-way optical transmitting/receiving module, an optical fiber resonant cavity, a single-mode transmission fiber, and an optical fiber sensing array, wherein the single-fiber two-way optical transmitting/receiving module is composed of a semiconductor light source as the transmitting terminal, a semiconductor photodetector as the receiving terminal and related devices packaged together; and an optical fiber annular cavity is composed of an optical fiber coupler, an optical fiber self-focusing lens and a movable corner reflector. The device can achieve enquiry and measurement of a plurality of optical fiber sensors by embedding the single-fiber two-way optical transmitting/receiving module and the optical fiber resonant cavity in the single-mode optical fiber, and has the advantages of simple structure, easy implementation, no length restriction of the transmission cable, no influence caused by the external environment, and good stability and reliability. The device can be used for the measurement of physical quantities such as distributed deformation, strain and temperature, and can be used for multi-task sensing, multi-element sensing, local strain sensing, large-scale deformation sensing, etc.

The invention relates to a fiber Bragg grating type wind farm wind velocity long-range detector which comprises a rotating shaft fixedly provided with a wind cup and is characterized in that a cam is arranged on the rotating shaft, a fixed seat is arranged on one side of the rotating shaft, a spring piece is arranged on the fixed seat, the top part of the spring piece is in contact with a rim of the cam, and a fiber Bragg grating is longitudinally fixedly arranged on the spring piece; the fiber Bragg grating is connected with an optical fiber coupler through an optical cable, and the optical fiber coupler is respectively connected with an optical fiber light source and a fiber Bragg grating demodulator; and the fiber Bragg grating demodulator is connected with a computer. The fiber Bragg grating type wind farm wind velocity long-range detector is mainly used for manufacturing the wind velocity detector.

The invention discloses an in-band full duplex underwater acoustic communication apparatus capable of suppressing interference from a digital domain and an analog domain. The full duplex underwater acoustic communication apparatus comprises a transmitting unit and a receiving unit, wherein the transmitting unit comprises a modulator, a digital-to-analog converter, a power amplifier and a transmitting transducer, and the receiving unit comprises a receiving hydrophone, a low-noise amplifier, an analog-to-digital converter and a demodulator. A receiving terminal is subjected to interference of near-end local transmitting signals while receiving remote signals and thus cannot acquire correct demodulated signals. According to the invention, a method for eliminating interference in the analog domain is selected to eliminate the interference, and part of self-interference can be eliminated. Furthermore, a method for eliminating interference in the digital domain is adopted, so that self-interference and inter-symbol interference are completely avoided. The underwater acoustic communication apparatus disclosed by the invention eliminates interference from the analog domain and the digital domain, thereby realizing in-band full duplex underwater acoustic communication in a real sense.

The invention provides a method and device for indicating configuration information, a base station and a terminal. The method includes the following steps: sending a generated first mapping relationship table of service parameters and configuration information to the terminal, wherein the service parameters include at least one of the following items: service types, radio bearers, logical channels, wireless network temporary identifiers, network slices and physical layer control channels, and different service parameters match the same or different configuration information; and sending firstscheduling control information to the terminal, wherein the first scheduling control information is used to instruct the terminal to select the specified configuration information from the received first mapping relationship table to perform data receiving or transmission. Thereby, the problem that the terminal cannot obtain the configuration information corresponding to different service types in time and cannot effectively receive and process the data transmitted by the base station in related technologies can be solved.

The invention relates to an allfiber type long period fiber grating solution multi-parameter sensing system. Broadband light source output light enters the input end of a 2*2 fiber coupler by a compound long period fiber grating; one path of output light of the 2*2 fiber coupler enters a first fiber Bragg grating; the other path of the output light enters a second fiber Bragg grating by a fiber isolator; the reflected light of the two fiber Bragg gratings is collected by a data capture card after entering a photoelectric conversion module and a signal amplifier; and a computer carries out data processing and real-time measurement result display. In the multi-parameter sensing system, the compound long period fiber grating serves as the sensitive elements of a plurality of parameters, matched fiber Bragg gratings serve as signal demodulation elements to realize the allfiber type multi-parameter sensing system. The allfiber type long period fiber grating solution multi-parameter sensingsystem has the advantages of electromagnetic interference, allfiber type measurement and the like and can be remotely monitored.

The invention discloses an information transmission method under an unauthorized frequency band, a network equipment and a terminal. The method comprises the following steps: according to the idle state of an unauthorized frequency band channel, determining the initial transmission position of the unauthorized frequency band channel in a current time domain transmission unit; If the start transmission position is located behind the start position of the current time domain transmission unit, a demodulated reference signal is transmitted to the terminal at a candidate transmission position of the demodulated reference signal. In order to solve the sending problem of NR-PDCCH and DMRS in the NR-LAA system due to the uncertainty of the available time of unauthorized frequency band channel, NR-PDCCH and DMRS are sent by adding candidate transmission positions of NR-PDCCH and/or DMRS to guarantee the normal demodulation of the received data information by the terminal.

The invention relates to a multi-carrier air-conditioning infrared signal self-learning controller and a method of the controller. The multi-carrier air-conditioning infrared signal self-learning controller comprises an MCU (Microprogrammed Control Unit) module, a plurality of infrared integrated receiving tubes, four input and gates, an EEPROM (Electronically Erasable Programmable Read-Only Memory) storage unit, a serial port communication unit, a key unit and an infrared transmission unit, wherein the four input and gates, the EEPROM storage unit, the serial port communication unit, the key unit and the infrared transmission unit are all connected with the MCU module; and each infrared integrated receiving tube is respectively connected with the four input and gates and the MCU module. The controller has the beneficial effects that the controller is in a sleeping state at ordinary times and is less in power consumption; infrared remote control signals can cause the external interrupt of a main control microprocessor, so that the main control microprocessor is in a self-learning state; and the infrared integrated receiving tubes are integrated, the crosstalk demodulation of a plurality of carrier encoded signals is realized, and learned carrier frequency bands are accurately distinguished, memorized and duplicated to achieve the purpose of remotely learning the multi-carrier air-conditioning infrared remote control signals.

The invention provides a method to measure the three-dimensional distortion of the object by the spatial carrier frequency electron speckle interference. It illumines the object by the three coherent lights of the horizontal, the vertical and the vertical to the surface of the object directions; it leads the carrier wave by controlling the deflection of the reflector in the horizontal and the vertical direction to adjust the interference fringe of the displacement field; it adjusts the interference fringe of the off-face displacement field by the deflection of the object. It gets the phase position of every distorted field by the Fourier transformation to reach the measurement of the three dimensions. The invention has the high delicacy and precision, soothe precision can be improved to 1/20 waves.

The invention discloses a long distance passive liquid level sensor based on distributed fibers, for solving the problem that a current fiber liquid level sensor has low accuracy and low stability. The long distance passive liquid level sensor based on distributed fibers comprises a light source, a comparison circuit, a wavelength division multiplexing device array formed by N wavelength division multiplexing devices, and a fiber array formed by N fibers, wherein pumping arms of the N wavelength division multiplexing devices are connected with the light source; signal arms of the N wavelength division multiplexing devices access the comparison circuit; beam combination arms of the N wavelength division multiplexing devices are correspondingly connected with head ends of the N fibers one to one; tail ends of the N fibers are measuring ends; the vertical distance between the end surfaces of the tail ends of the two adjacent fibers is x, and x is the measuring accuracy to be achieved. The long distance passive liquid level sensor based on distributed fibers can determine the liquid level position according to the abrupt change position of luminous intensity, being similar to digital detection, wherein the measuring accuracy is mainly decided by the distributed spacing of the fibers. Besides, the long distance passive liquid level sensor based on distributed fibers can eliminate the influence of energy shaking of light source and external disturbance on measurement, is slightly influenced by environment, and has high measuring accuracy and high stability.

The invention discloses an optical mixer and a method for demodulating a signal through the optical mixer. The optical mixer comprises two cubic unpolarized beam splitters (BS) and two cubic polarized beam splitters (PBS), wherein a cuboid block is formed by the two BSs and the two PBSs, the beam splitting interfaces of the two BSs are located in a first plane, the beam splitting interfaces of the two PBSs are located in a second plane, and the first plane is perpendicular to the second plane. According to the embodiment, the planar optical waveguide PLC technology is not used in the optical mixer, demodulation to the modulated signal is achieved through the two cubic unpolarized BSs and the two cubic PBSs, and the BSs and the PBSs are lower in cost, smaller in insertion loss, higher in temperature stability and based on space optics. Therefore, the cost of the optical mixer is reduced, the insertion losses of the optical mixer are reduced, and the temperature stability of the optical mixer is improved.

The invention discloses a multi-antenna space-based AIC receiver, and the receiver comprises an antenna array, a radio frequency front end, and a digital processing unit. The antenna array comprises a plurality of monopole antennas, and receives an AIS signal of a marine ship. The radio frequency front end comprises a plurality of radio frequency receiving channels, and completes the amplification filtering and frequency conversion of a radio frequency signal. The digital processing unit employs a blind separation and differential demodulation method to complete the separation and demodulation of multi-time-slot collision signals. The receiver is advantageous in that the number of multi-time-slot collision signals is large; the demodulation method is simple; the receiver can effectively monitor a high-ship-density sea area; the receiver exerts no special requirements for the array shape and aperture, and is especially suitable for a small-satellite platform.

The invention discloses a multi-rate demodulating device based on sampling point selection, and belongs to the technical field of satellite-borne communication. The device comprises an orthogonal down-converter, a multi-rate extraction filter, an optimal sample point selector, a carrier phase tracker, a decoder and a framing processor. According to the device, timing recovery is realized by adjusting data output of the extraction filter and selecting an optimal sampling point; and the device has the advantages of simple processing implementation, low resource occupation, multi-rate support andthe like, and is particularly suitable to be used as a medium-low-speed multi-rate signal demodulating device which is limited in inter-satellite or satellite-ground resources.

The invention belongs to the field of satellite data transmission and particularly relates to an interpolation estimation method in parallel demodulation bit synchronization. According to the scheme, data sampled by a receiver are parallelized, the processing speed in an FPGA is reduced, and the problems related to the design of an NOC and computation of an interpolation moment in parallel demodulation bit synchronization are solved. The interpolation estimation method has the uppermost advantage that deceleration can be conducted on high-speed data collected by the receiver so that the corresponding demodulation process can be achieved in the FPGA.

The invention provides an underground pipeline monitoring system and method based on distributed optical fiber sensing. An armored photoelectric composite cable arranged on the outer side of an underground pipeline , a high-resolution optical camera with a night vision function and mounted along an underground pipeline, and an automatic monitoring and early warning system and a DSS/DTS/DAS composite distributed optical fiber sensing modulation and demodulation instrument which are arranged in a monitoring station along the line are used to construct a long-term real-time monitoring system forthe temperature, vibration and strain distribution change along the underground pipeline based on distributed optical fiber sensing. Real-time effective anti-theft, anti-excavation damage, fireproof,anti-natural and geological disaster early warning monitoring is carried out on underground pipelines and oil and gas conveying pipelines; loss can be effectively avoided or reduced; long-term stable,safe and reliable work of the underground pipelines is guaranteed; and indispensable means, systems and methods are provided for scientific management of the underground pipelines and improvement ofthe use efficiency.

The invention discloses a broadband radio frequency remote optical transmission link and a transmission method thereof, relating to the microwave photon simulation optical link transmission technology field. The link comprises the following parts: an electric light polarization modulator used for carrying out anti-phase phase modulation on a broadband radiofrequency signal to two carrier wave optical signals of a main shaft and a quadrature shaft and outputting the two carrier wave optical signals to a polarization analyzer; the polarization analyzer used for outputting a modulation optical signal setting a polarization direction; a detector used for demodulating an input modulation optical signal, realizing direct noncoherent synthesis of power, and recovering broadband radio frequency information loaded on the modulation optical signal. The transmission link and the method in the invention have the characteristics of realization of broadband dispersion compensation, simple link structure, low cost and easy adjusting control.

The invention discloses a parameter optimization method for a communication integration signal of an asymmetric triangular frequency modulation radar. The shape of a frequency curve of the integration signal is an asymmetric triangle, and the integration signal consists of two LFM (linear frequency modulation) signals with opposite frequency modulation ratio symbols. The first signal is an LFM signal with the frequency modulation ratio k1, has no modulated communication information and is used for the synchronization or capturing of a communication signal, and the second signal is an LFM signal with the frequency modulation ratio k2, wherein k1*k2 is less than zero. Communication code element information is modulated on the second signal in a mode (-1, 1). The method is based on a parameterized model of the communication integration signal of the asymmetric triangular frequency modulation radar, and employs a fuzzy function for representing radar detection performances and a target function for representing communication performances to optimize and design the parameters of the integration signal. The method guarantees the probability of successful capturing of communication through employing a shortest synchronization signal, and guarantees an information transmission rate at a certain signal to noise ratio under the condition of guaranteeing the radar detection performances.

The invention discloses a channel prediction method for deep space exploration under weak solar scintillation. A second order AR model is adopted for describing a scintillation power spectrum. A solarscintillation amplitude fluctuation predicting equation is y[n+i] = b1y[n-1] + b2y[n-2]. In the formula, i is greater than or equal to 0 and indicates the jth prediction; and b1 and b2 are predictioncoefficients and are obtained by adopting linear minimum mean square error, namely LLS. By means of signaling channel prediction, the signaling channel predicting method can improve the power use efficiency of an emitter of a detector, establish a reliable transmission link between the detector and the earth and realize the self-adaptive power control, modulation and demodulation of the deep space detector, thereby being favorable for improving the resource use efficiency and detection efficiency of the deep space exploration. The signaling channel predicting method is suitable for the heterogeneous communication environment such as a wireless sensing network, a self-organized network and the like, and assumes good transformation application prospect in aerospace, aviation, military affairs, social economy and other fields.

The invention relates to a demodulation method of a multi-core fiber Bragg grating curvature sensor. According to the method, the change of the center wavelength of an optical fiber Bragg grating is converted into the change of the reflection power of the optical fiber Bragg grating by using a cosine type broadband light source; and a corresponding center wavelength is calculated through measuring the reflection power of the optical fiber Bragg grating according to a derived relational expression of the reflection power and center wavelength of the optical fiber Bragg grating, so that the demodulation of the center wavelength of the optical fiber Bragg grating is realized. The multi-core fiber Bragg grating curvature sensor includes two optical fiber Bragg gratings which are respectively located in two fiber cores which are in central symmetry with respective to the section of a multi-core fiber; the change quantity of the center wavelength of the two optical fiber Bragg gratings is obtained according to the FBG center wavelength demodulation method, so that a corresponding curvature value can be obtained. The curvature sensor demodulation technology has the advantages of high sensitivity, simple realization mode, low cost and the like.

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 relates to the technical field of wireless communication, and particularly relates to an enhanced six-dimensional 64PSK constellation-based orthogonal frequency division multiplexing method. According to the enhanced six-dimensional 64PSK constellation-based orthogonal frequency division multiplexing method, a two-dimensional constellation mapping-based orthogonal frequency division multiplexing technology is expanded to a six-dimensional signal space; and under a same average power, the enhanced six-dimensional 64PSK constellation-containing orthogonal frequency division multiplexing technology is capable of enlarging the minimum Euclidean distance between signal points in the signal space so as to obtain relatively high demodulation gain and bandwidth efficiency. Experiments prove that compared with the traditional orthogonal frequency division multiplexing technology, the method has lower bit error rate, so that an orthogonal frequency division multiplexing technology which is higher in speed and more reliable is provided to the future wireless sensor network physical layer protocol design.