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74 results about "Polarization diversity" patented technology

Polarization diversity. A method of transmission and reception used to minimize the effects of selective fading of the horizontal and vertical components of a radio signal; it is usually accomplished through the use of separate vertically and horizontally polarized receiving antennas.

Thermal wave imaging detection method based on nonlinear frequency modulation microwave excitation and induction

The invention provides a thermal wave imaging detection method based on nonlinear frequency modulation microwave excitation induction, and the method comprises the steps: constructing a composite excitation module of Gaussian beam and dynamic phase compensation, decomposing high-frequency / low-frequency sub-pulses for alternate emission, synchronously collecting infrared non-uniform sampling and microwave polarization diversity data, and carrying out the detection of the thermal wave imaging. And through feature fusion of a time domain CNN and a frequency domain graph neural network, propagation parameters are iteratively corrected in combination with a thermal diffusion equation model, and defect and deep structure detection is realized. According to the method, the composite excitation structure is combined with high-frequency / low-frequency sub-pulse alternate emission, the micro-defect detection resolution and the deep structure penetrating capacity are remarkably improved, the feature robustness is enhanced through multi-modal data acquisition and cross-modal neural network fusion, detection depth self-adaptive optimization is achieved through a depth compensation model and Kalman filtering, and the detection precision is improved. The parameter precision is improved with the assistance of a terahertz spectrum coupling matrix and Landweber iterative inversion, and finally an advanced detection system integrating efficient excitation, multi-dimensional perception and intelligent analysis is formed.
Owner:SHAANXI SCI CONTROL TECH IND RES INST CO LTD

Distributed optical fiber monitoring system and method for faults of carrier rollers of belt conveyor

The invention relates to the technical field of belt conveyor carrier roller fault monitoring, and discloses a belt conveyor carrier roller fault distributed optical fiber monitoring system which comprises a double-light-source DAS system, optical fiber information acquisition, filtering preprocessing, time domain analysis, time-frequency domain analysis, phase analysis, multi-mode feature fusion, fault classification and fault position and grade output. By building a dual-light-source polarization diversity DAS system and combining an adaptive filtering preprocessing technology, high signal-to-noise ratio acquisition and noise reduction processing of vibration signals are realized, dual-light-source orthogonal polarization state transmission effectively suppresses polarization fading, wavelet packet denoising and variable-step LMS filtering collaboratively filter environmental noise and pulse interference, and the noise reduction performance of the vibration signals is improved. Meanwhile, the application of the dynamic weighted root-mean-square value and the continuous wavelet transform ensures the accurate capture of the time domain energy characteristic and the frequency domain time-varying characteristic, and lays a reliable foundation for the multi-modal characteristic fusion.
Owner:XUZHOU ANRONG MASCH MFG CO LTD

Polarization diversity and frequency diversity combined low-altitude communication anti-interference system and channel allocation method

The invention provides a polarization diversity and frequency diversity combined low-altitude communication anti-interference system and a channel allocation method, and relates to the technical field of low-altitude communication, and the system is composed of a multi-polarization antenna array, a broadband radio frequency front end, a digital signal processing unit, a self-adaptive controller and an environment sensing module. The core of the invention is a polarization-frequency joint channel allocation method, and global optimal allocation of channel resources is realized by constructing a polarization-frequency two-dimensional channel quality matrix. The system adopts a multi-layer adaptive architecture and comprises a quick response layer and a deep optimization layer, so that the real-time performance and the optimization degree are balanced. In addition, the invention also provides an anti-intelligent interference diversity parameter dynamic adjustment mechanism and an interference identification method based on polarization characteristics, so that the communication reliability and the anti-interference capability of the system in a complex electromagnetic environment are remarkably improved. And communication with an extremely low bit error rate can still be kept in a strong interference environment.
Owner:UBISOFT TECH CO LTD

Multi-Channel Electro-Optic Receiver with Polarization Diversity and Timing-Skew Management

An electro-optic receiver includes a polarization splitter and rotator (PSR) that directs incoming light having a first polarization through a first end of an optical waveguide, and that rotates incoming light from a second polarization to the first polarization to create polarization-rotated light that is directed to a second end of the optical waveguide. The incoming light of the first polarization and the polarization-rotated light travel through the optical waveguide in opposite directions. A plurality of ring resonators is optically coupled the optical waveguide. Each ring resonator is configured to operate at a respective resonant wavelength, such that the incoming light of the first polarization having the respective resonant wavelength optically couples into said ring resonator in a first propagation direction, and such that the polarization-rotated light having the respective resonant wavelength optically couples into said ring resonator in a second propagation direction opposite the first propagation direction.
Owner:AYAR LABS INC

Dual-frequency dual-polarization duplex phased array for multi-standard communication

The invention discloses a dual-frequency dual-polarization duplex phased array for multi-standard communication, aims to solve the technical bottleneck of the existing millimeter wave phased array in frequency band compatibility, polarization diversity and duplex operation, and comprises a millimeter wave broadband dual-polarization end-on-fire antenna and a dual-frequency dual-polarization duplex phased array architecture. According to the phased array established by the invention, four sets of independent beam forming systems are integrated on a single printed circuit board and correspond to a first frequency band vertical polarization channel, a first frequency band horizontal polarization channel, a second frequency band vertical polarization channel and a second frequency band horizontal polarization channel respectively, and concurrent transmission and independent beam control of dual-frequency-band and dual-polarization signals are supported. The phased array realizes two-dimensional expandability based on a brick-shaped framework, can be used for constructing a planar array, and is suitable for a large-scale deployment scene. The compact size and low-cost scheme provides a high-integration, high-flexibility and high-reliability communication solution for B5G / 6G multi-standard scenes such as intelligent transportation, industrial Internet of Things and smart home.
Owner:SOUTHEAST UNIV

Multi-functional shared aperture 8n-port MIMO antenna system

Embodiments herein disclose an antenna system comprising a plurality of panel comprising at least one Multiple Input Multiple Output (MIMO) antenna array, including a plurality of microstrip patch antenna elements and stacked patch antenna elements. The microstrip patch antenna elements, configured in a linear array, facilitate a lower operating frequency, while the stacked patch antenna elements, placed atop the microstrip patch antenna elements, achieve a higher operating frequency. The stacked patch antenna elements are connected in series and oriented at a predefined angle of 90° relative to the microstrip patch antenna elements. A panel from the plurality of panels is arranged at a pre-defined angle of 90° relative to an adjacent panel from the plurality of panels for polarization diversity to obtain the multifunctional shared aperture 8N-port MIMO antenna system.
Owner:INDIAN INSTITUTE OF TECHNOLOGY

Method and system for optical switching with integrated polarization diversity control

A method and system for optical switching with integrated polarization diversity control comprising a beam displacer to receive an input beam and split the input beam into a first beam and a second beam with linear polarization. The first and second beams may be received on a liquid crystal cell that may rotate the first or second beam so that both beams have the same polarization after traversing the liquid crystal cell. Based on the polarization, the output beam may be switched to a port.
Owner:II VI DELAWARE INC

High-gain millimeter-wave polarization reconfigurable antenna

The application discloses a high-gain millimeter wave polarization reconfigurable antenna and belongs to the technical field of wireless communication.The application provides a high-gain millimeter wave polarization reconfigurable antenna, and the whole antenna structure is completed on two layers of dielectric substrates.Polarization diversity is realized by connecting the center patch of two groups of parasitic short columns by using pin diode switches, and the polarization state can be switched in the directions of ±45 degrees.Then, in order to improve the radiation performance of the antenna, an extended semi-ellipsoid lens is added to the antenna, so that the antenna gain is increased by about 10 dB, and therefore, the integrated lens antenna is an effective method for developing the millimeter wave polarization reconfigurable antenna.The gain-enhanced polarization reconfigurable antenna has the advantages of high gain, low cost and stable radiation pattern and is an ideal choice for low-cost millimeter wave applications of the fifth generation (5G) communication technology.
Owner:ANHUI AGRICULTURAL UNIVERSITY

Rock mechanics test acoustic emission signal collection device and positioning method

The application discloses a kind of rock mechanics test in the collection device of acoustic emission signal, including computer, measurement and control and signal processing equipment, distributed acoustic wave sensing equipment and collection probe: the collection probe is composed of single-mode optical fiber and probe skeleton, single-mode optical fiber is fixed around probe skeleton, when testing, collection probe is fixed on the surface of rock sample for testing;The measurement and control and signal processing equipment include: radio frequency amplifier, digital-to-analog conversion module, analog-to-digital conversion module, filter amplifier, field programmable logic gate array and CPU-GPU data processing module;The distributed acoustic sensing equipment includes narrow linewidth laser, fiber coupler, acoustooptic modulator, erbium-doped fiber amplifier, circulator, polarization diversity receiver, first balanced photodetector and second balanced photodetector;Collection signal band is wide, can be conveniently installed on any rock sample.Collecting main frequency is lower, collection probe is connected closely with rock sample, coupling is good, without additional smearing coupling agent.
Owner:XIAN RES INST OF CHINA COAL TECH & ENG GRP CORP +1

Electromagnetic sensor array for dual-band direction finding

The invention discloses an electromagnetic sensor array for dual-band direction finding. The electromagnetic sensor array comprises three dual-band electric sensors and three dual-band magnetic sensors, the dual-band electric sensors are used for measuring electric field components in the Z-axis direction and are equally distributed according to the radial distance d and the angular spacing of 120 degrees; the dual-band magnetic sensors are used for measuring magnetic field components in the X-axis direction and the Y-axis direction and are equally distributed according to the radial distance of d / 2 and the angular spacing of 120 degrees. The electromagnetic sensor array for dual-band direction finding disclosed by the invention has the beneficial effects that the electromagnetic sensor array is simple in structure and easy to process and manufacture; measurement of a dual-band electric field and a dual-band magnetic field is achieved, and the dual-band electric field and the dual-band magnetic field can be expanded to multiple bands through The spatial diversity of a scalar array and the polarization diversity of a vector array are fused, and the unambiguous accurate estimation of the direction of arrival of an incident electromagnetic signal is realized in the range of an incident pitch angle of 20-85 degrees and an incident azimuth angle of 0-360 degrees by optimizing the array topology.
Owner:YANGTZE DEITA GRADUATE SCHOOI OF BEIJING INST OF TECH (JIAXING)

Frequency diversity and polarization diversity transmission system based on diversity antennas

The application provides a frequency diversity and polarization diversity transmission system based on diversity antennas, comprising a diversity antenna subsystem, a radio frequency feeding network and a baseband processing unit, the diversity antenna subsystem comprises a first diversity antenna, a second diversity antenna and a metal floor, the first diversity antenna and the second diversity antenna are both at least dual-frequency antennas and are placed in space orthogonally, the radio frequency feeding network comprises a signal phase shifter, an equivalent phase shifter, a power divider and a signal amplifying device, and can realize frequency diversity and twice polarization diversity. The frequency diversity and polarization diversity transmission system based on diversity antennas provided by the application realizes the collaborative innovation of a radio frequency front end and a baseband processing unit, and constructs a complete radio frequency baseband architecture which can simultaneously and actively realize the collaborative processing of polarization diversity and frequency diversity.
Owner:JIMEI UNIV

Coherent receiver with polarization diversity clock detection

A receiver includes an optical front-end and digital circuitry. The optical front-end is configured to receive an optical signal including first and second optical signal components having first and second polarizations and modulated with symbols at a symbol rate. The digital circuitry is configured to derive first and second digital signals representing the first and second optical signal components having the first and second polarizations. The digital circuitry includes a clock detector configured to calculate correlation terms, the correlation terms being calculated in a frequency-domain with a frequency offset commensurate with the symbol rate. The clock detector is configured to recover a clock signal of the symbols by (i) summing selected pairs of the correlation terms, and (ii) calculating or estimating a sum-of-squares of the summed pairs.
Owner:MARVELL ASIA PTE LTD

A method for intravascular polarization sensitive optical coherence tomography medium depolarization measurement

This invention relates to a method for measuring the depolarization of a medium in intravascular polarization-sensitive optical coherence tomography (ICP-CT), comprising: setting the polarization state of the input light of a catheter polarization-sensitive optical coherence tomography system; setting the reference light in the H and V channels of the input light and the reference light in the system to have equal intensity; acquiring the electrical signals measured at the polarization diversity point in the form of a Jones matrix to obtain the average measurement Mueller matrix; calculating the standard deviation matrix of the reference region; obtaining the depolarization Mueller matrix of the reference region; extracting the block matrix of the average measurement Mueller matrix of the reference region; calculating the average double attenuation block matrix of the reference region; constructing the average double attenuation matrix of the reference region; obtaining the pseudo-average birefringence phase delay matrix of the reference region; extracting the average depolarization matrix of the reference region from the pseudo-average birefringence phase delay matrix of the reference region using matrix decomposition; obtaining the depolarization Mueller matrix of the target region; and calculating the medium depolarization coefficient.
Owner:TIANJIN UNIV

Terahertz electrically controlled diversity switched dual-band reconfigurable intelligent surface

The application discloses a terahertz electrically controlled polarization diversity dual-band reconfigurable intelligent surface, which comprises a metal bottom plate, a dielectric substrate and a phase shift structure layer arranged layer by layer from bottom to top; the phase shift structure layer comprises phase shift units arranged in an M*N orthogonal array mode, each column of the phase shift units has an anode lead-out wire and a cathode lead-out wire; each phase shift unit comprises three dipoles, and the dipole is in an I-shaped structure and is formed by two T-shaped branches arranged oppositely at vertices. The application works through electric control, thereby realizing dynamic broadband regulation and control of the phase. Without other relatively complex excitation modes such as optical excitation and temperature excitation, the device has great advantages in miniaturization, practicality and production.
Owner:YANGTZE DELTA REGION INST OF UNIV OF ELECTRONICS SCI & TECH OF CHINE (HUZHOU) +1

Distributed fiber optic sensing system for measuring temperature and strain based on OCDR-SOCF

A distributed fiber optic sensing system for measuring temperature and strain based on OCDR-SOCF (Optical Detection and Conversion) technology includes a laser, an isolator, a collimator, a polarization controller, a coupler, an acousto-optic modulator (AOM), a polarization diversity photodetector (PDD), and a signal acquisition and processing module. The laser light generated by the laser passes through the isolator and enters a Michelson interferometer. One path of the laser light is calibrated by the collimator and injected into the optical fiber. The returned Rayleigh backscattered light passes through the polarization controller and is then injected into the coupler. The other path of the laser light passes through the acousto-optic modulator and is then injected into the coupler. The two signals enter the polarization diversity photodetector, where they interfere and generate a current signal, which is then output to the signal acquisition and processing module. The signal acquisition and processing module synthesizes the coherence function to achieve simultaneous fiber temperature and strain sensing. This system facilitates measurement, reduces system complexity, and reduces system cost.
Owner:SHANGHAI JIAOTONG UNIV

Photonic integrated circuit for high-wavelength-channel-count wavelength-division-multiplexed systems

The present disclosure is directed toward architectures that combine DWDM and CWDM concepts in a single PIC. Transmitter stages in accordance with the present disclosure include a plurality of multiwavelength lasers having regions of separately grown epitaxial material whose gain peaks are centered at different wavelengths. Each laser launches a wavelength comb comprising a plurality of wavelength signals into a PLC, where the wavelengths within each wavelength comb are separated by a wavelength spacing that is smaller than that between adjacent wavelength combs. In some embodiments, the PLC includes modulator banks for encoding data on the wavelength signals and combining them to produce a composite DWDM output signal. In some embodiments, a receiver stage is included for demultiplexing a composite DWDM input signal and detecting each wavelength channel within it. In some embodiments, the receiver stage employs polarization-diversity techniques to enable it to operate on unpolarized / randomly polarized input signals.
Owner:QUINTESSENT INC

On-chip adaptive wave combination method and feedback system for polarization diversity MZM

The invention relates to the field of silicon-based optoelectronic integration, and particularly discloses an on-chip adaptive wave combination method and feedback system for a polarization diversity MZM, and the system comprises an optical coupling and mode conversion module, a polarization diversity electro-optical modulation module, an optical power collection and photoelectric conversion module, a signal processing and feedback control module, and a tunable wave combination module. After coupling conversion and modulation, two paths of optical power are collected and subjected to photoelectric conversion, a power difference voltage is obtained through an analog circuit, a bias voltage is superposed to generate a control voltage, and an adjustable combiner is driven to dynamically adjust the beam splitting ratio to complete wave combination. The problems that the output power of the polarization diversity MZM fluctuates randomly along with the polarization state, and an existing polarization control scheme is slow in response, complex in architecture and difficult to integrate with a silicon-based process are solved, real-time accurate compensation of power fluctuation is achieved, it is guaranteed that the combined wave output power is stable, the system architecture is simple, power consumption is low, integration with a silicon-based chip monolithic chip is easy, and the application range is wide. And the performance and the compatibility of the integrated photonic link are improved.
Owner:TIANJIN GUANGXI INFORMATION TECHNOLOGY CO LTD

Integrated optical circulator implementing polarization diversity

Integrated optical circulators that enable polarization diversity are disclosed. A photonic integrated circulator (200) can be fabricated by including multiple polarization beam splitters (220, 222) and optical polarization rotators (230, 232, 234) such that two copies of an optical signal are output at a receiver in substantially aligned polarization states. The circulator (200) can be used to facilitate bidirectional communication between photonic integrated circuit devices that are inherently polarization sensitive while reducing signal loss.
Owner:GOOGLE LLC

Polarized antenna

The utility model provides a polarized antenna, comprising a first antenna substrate on which a horizontal polarized antenna array is arranged; the first edge of the second antenna substrate is connected with the second edge of the first antenna substrate, and a preset angle is formed between the first antenna substrate and the second antenna substrate; and a dual-polarized antenna array is arranged on the second antenna substrate. The polarized antenna is installed on an antenna holding pole beside a track or a building, so that the second antenna substrate is right opposite to the track or the building, a wave beam formed by the dual-polarized antenna array correspondingly covers an area at a small incident angle, and a polarization diversity effect is reserved in an area where vertical polarized waves have good penetrability. The first antenna substrate is correspondingly arranged on the side face of the antenna holding pole, a wave beam formed by the horizontal polarization antenna array corresponds to a coverage area at a large incidence angle, and horizontal polarization has better projectability compared with vertical polarization, so that the problem that a part of energy is wasted due to the fact that vertical polarization components of the antenna are reflected is solved.
Owner:CHINA MOBILE COMM LTD RES INST +1

Method for controlling optical amplification device

A method according to one embodiment of the present disclosure for controlling an optical amplification device (10) of a polarization diversity configuration comprises: detecting a first optical intensity of first polarized waves from a first amplifier (102) which is disposed between a polarization splitter (121) and a polarization combiner (122); detecting a second optical intensity of second polarized waves from a second amplifier (103) which is disposed between the polarization splitter (121) and the polarization combiner (122); detecting a third optical intensity of the first polarized waves from the polarization combiner (122) in a state where the second polarized waves are not input to the polarization combiner (122); detecting a fourth optical intensity of the second polarized waves from the polarization combiner (122) in a state where the first polarized waves are not input to the polarization combiner (122); and acquiring loss of the first polarized waves from the first amplifier (102) to the polarization combiner (122) and loss of the second polarized waves from the second amplifier (103) to the polarization combiner (122) on the basis of the first optical intensity, the second optical intensity, the third optical intensity, and the fourth optical intensity.
Owner:NT T INC

Four-polarization and wave beam composite reconfigurable antenna array based on 1bit control

The invention provides a four-polarization and wave beam composite reconfigurable antenna array based on 1bit control, which belongs to the technical field of antennas and comprises M * N microstrip patch antenna units in rectangular arrangement and a feed network, the microstrip patch antenna unit independently controls the on-off of a diode through two paths of bias lines, so as to realize 1-bit phase regulation and control of X polarization and Y polarization; the feed network comprises a power divider and a delay line; the delay line is respectively connected with the output end of the power divider and the input end of the microstrip feeder layer of the microstrip patch antenna unit; by adopting the delay lines with different lengths, each microstrip patch antenna unit has different initial phases. According to the invention, periodic phase errors caused by 1bit control are eliminated at low cost, the four-polarization reconfigurable antenna array is constructed, and rapid switching of polarization diversity and wave beam states is realized.
Owner:HEFEI RHOSOON INTELLIGENT TECH CO LTD

Distributed optical fiber sound wave sensing system applied to long-distance heat distribution pipeline monitoring

The invention discloses a distributed optical fiber sound wave sensing system applied to long-distance heat distribution pipeline monitoring, and the system comprises a laser which generates laser required by the system; the coupler divides emergent light of the laser into two paths, one path serves as probe light to enter the electro-optical modulator, and the other path serves as local oscillation light to enter the polarization diversity receiver; the probe light enters the electro-optical modulator and then is modulated into a sweep frequency pulse signal, a scattering signal generated by the probe light at the sensing optical fiber is input into the polarization diversity receiver through the circulator and enters the balance detector after being mixed with the local oscillation light, and a generated electric signal is input into the data acquisition card and enters the upper computer for demodulation; the method has the beneficial effects that the linear sweep frequency pulse is used as the detection light, so that the method has a relatively large sweep frequency range, the spatial resolution of the system is greatly improved on the premise of not reducing the maximum monitoring distance, the event position can be accurately positioned in a long-distance heat distribution pipeline monitoring scene, and the alarm accuracy is improved.
Owner:SHANDONG FEIBOSAISI PHOTOELECTRIC TECH CO LTD

Light vector analysis device and method for unbalanced cross-polarization inquiry

The invention belongs to the technical field of light wave element measurement, and particularly relates to a light vector analysis device and method for unbalanced cross-polarization inquiry, and the device comprises a sweep frequency light source module, a cross-polarization generation module, a measurement interferometer module, a polarization diversity detection module, and a module for obtaining information of a device to be measured. The device is characterized in that an orthogonal polarization generation module composed of a coupler and a polarization beam combiner generates a pair of orthogonal polarization frequency sweeping lasers with a high extinction ratio, and a complicated polarization regulation and control process with the extinction ratio difficult to guarantee is not needed any more. Meanwhile, the tail fibers of all the optical fiber devices in the device are common single-mode optical fibers, so that the error influence of polarization crosstalk on the measurement result is effectively avoided, and the spectral response characteristic measurement precision of the optical device to be measured is greatly improved.
Owner:GUANGDONG UNIV OF TECH

Laser dynamic speed measurement system and laser dynamic speed measurement method for highway vehicles in rainy and foggy weather

The application provides a laser dynamic speed measurement system and a laser dynamic speed measurement method for vehicles on a highway in rainy and foggy weather. The method comprises the following steps: collecting echo signals of a laser beam reflected by vehicles; performing polarization diversity detection on the echo signals to separate polarization components and obtain speed signals and displacement signals of the vehicles; determining multiple frequency shifts of the laser based on the speed signals, determining instantaneous speeds of the vehicles according to all the frequency shifts and the wavelength of the speed signals; performing stripping compensation on a time-varying phase of the displacement signals according to all the instantaneous speeds, and obtaining displacement reconstruction signals; performing equal optical frequency interval resampling on the displacement reconstruction signals through a preset beat frequency signal, and then determining observation distances of the vehicles according to the resampling results; correcting speed deviations according to all the time differences and all the observation distances, and obtaining dynamic speeds of the vehicles on the highway in rainy and foggy weather. The method can realize high-precision dynamic speed measurement of multiple vehicles on a highway under the interference of rainy and foggy weather.
Owner:CHENGDU UNIV

Distributed optical fiber sensing system based on anti-conjugate convolution algorithm

The invention discloses a distributed optical fiber sensing system based on an anti-conjugate convolution algorithm, and belongs to the technical field of optical sensing. According to the invention, through measurement of a detection pulse signal and anti-conjugate convolution of the detection pulse signal and a return light signal, detection of a strained signal, suppression of influence brought by line width and frequency sweeping nonlinearity and improvement of detection resolution are realized, and through a polarization diversity collection system and a weight superposition algorithm of frequency division multiplexing, the detection precision is improved. And the suppression of polarization weakening and coherent weakening of the signal is realized. Compared with a traditional OFDR system, the system and the algorithm have the advantages that the influence of frequency sweep nonlinearity and linear broadband can be suppressed, the distance limitation of OFDR detection can be lengthened, the conjugate relation between the signal-to-noise ratio and the resolution of a detection signal can be flexibly controlled through the corresponding algorithm, and the system can adapt to different application scenes.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA)

A heterogeneous data fusion transmission method and system for airborne multi-mode satellite communications

The present application relates to the field of data fusion transmission technology, and provides a heterogeneous data fusion transmission method and system for airborne multi-mode satellite communications. Real-time communication parameters are obtained, including dynamic spectrum occupancy status, polarization direction differences, and concealed transmission requirement levels; dynamic frequency hopping control instructions are generated based on the time-varying characteristics of the dynamic spectrum occupancy status to drive carrier switching and retain the spectrum isolation area between adjacent carriers; orthogonal polarization diversity analysis is performed on the carrier switching results based on polarization direction differences to suppress cross-polarization interference and output multi-path baseband signals; modulation parameters are determined by calling the preset waveform parameter library according to the concealed requirement level, and the baseband signal is loaded onto the asymmetric phase subcarrier to generate a concealed modulation waveform; the frequency hopping instructions are integrated with the concealed modulation waveform to generate a coordinated modulation instruction, and the radio frequency unit is controlled to achieve anti-interference fusion transmission. The technical solution provided by the present application improves the anti-interference capability of fusion transmission of multi-mode satellite data in a dynamic spectrum environment.
Owner:SINO FLYING VIDEO HI-TECH CO LTD

Wideband polarization diversity wearable receiving antenna system for capsule endoscope system and capsule endoscope system comprising broadband polarization diversity wearable receiving antenna system

The invention discloses a broadband polarization diversity wearable receiving antenna system for a capsule endoscope system and the capsule endoscope system comprising the broadband polarization diversity wearable receiving antenna system, and the wearable receiving antenna system comprises a flexible wearable carrier and a multi-antenna combination array integrated in the flexible wearable carrier; the multi-antenna combination array is composed of at least two independent antenna units. The antenna units have different preset resonant frequencies, and the resonant frequencies take a common reference frequency f0 as a center and are progressively shifted according to a preset step frequency value f to jointly form a synthetic receiving frequency band of which the coverage is wider than the bandwidth of a single antenna; meanwhile, the polarization directions of the antenna units are different from each other, and the antenna units sequentially rotate by a certain angle on the horizontal plane to jointly form a polarization diversity receiving array. On the premise of not depending on an active tuning circuit, the system can passively adapt to body type differences of different users, and effectively capture incoming waves in any polarization direction, so that the stability and success rate of image data receiving are improved.
Owner:WUXI FUSHENG SMART MEDICAL TECH CO LTD

Polarization diversity detection for fmcw lidar

The invention relates to a system and method for classifying an object. The system comprises a polarization beam splitter, a first detector, a second detector, and a processor. The polarization beam splitter generates a first source signal having a first polarization direction and a second source signal having a second polarization direction. The first detector transmits the first source signal at the object and receives a first reflection signal generated at the object in response to the first source signal. The second detector transmits the second source signal at the object and receives a second reflection signal generated at the object in response to the second source signal. The processor is configured to compare the first reflection signal and the second reflection signal to classify the object.
Owner:GM GLOBAL TECHNOLOGY OPERATIONS LLC

A phase-sensitive optical time-domain reflectometer based on orthogonal frequency division multiplexing pulse coding

This invention relates to a phase-sensitive optical time-domain reflectometer based on orthogonal frequency division multiplexing (OFDM) pulse coding. A continuous laser beam is split into a local path and a probe path via an optical coupler. The probe path, driven by a radio frequency signal, generates multiple frequency-orthogonal intensity-coded pulse sequences through an optical intensity modulator. These sequences are arranged sequentially in time, possessing the same symbol information but different chip sequences. The Rayleigh backscattered light generated by the pulse sequences entering the sensing fiber under test undergoes coherent interference with the local light in an optical bridge and polarization diversity module. The signal acquisition circuit utilizes an unmatched filter to achieve pulse compression and Rayleigh scattering signal separation, and synthesizes the results of the pulse coding sequences at each frequency to obtain the strain signal. Compared with existing technologies, this invention achieves pulse compression by designing an unmatched filter, improving the signal-to-noise ratio while maintaining spatial resolution. Furthermore, by synthesizing the results of orthogonal frequency pulse sequences, coherent fading is eliminated, achieving fading-free, high signal-to-noise ratio strain measurement.
Owner:NINGBO LIANHE PHOTONICS TECH CO LTD +1

Dual-polarization filtering multi-beam antenna array and method based on filtering jumper

The invention belongs to the field of multi-beam antenna arrays, and discloses a dual-polarization filtering multi-beam antenna array and method based on a filtering jumper, structural integration is realized by vertically stacking an energy feeding module, a beam forming network and a dual-polarization antenna module, the beam forming network adopts a plurality of groups of orthogonally arranged 2D Butler matrixes, and the beam forming network adopts a plurality of groups of orthogonally arranged 2D Butler matrixes; and a filtering jumper is embedded at a cross node, and same-frequency / different-frequency work is realized through independent frequency control of vertical and horizontal channels. According to the antenna array, through the synergistic effect of the filtering jumper and the Butler matrix, the functions of multi-band filtering, beam forming and dual polarization are achieved in a single system at the same time, and the problems that in a traditional scheme, the frequency band is single and the polarization capacity is insufficient are effectively solved; the frequency band adaptability and the polarization diversity capability of the antenna array in a complex environment are remarkably improved, and a more compact and multifunctional high-performance radio frequency front-end solution is provided for a 5G / 6G communication system.
Owner:NINGBO ORIENTAL UNIVERSITY OF TECHNOLOGY