Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

217 results about "Narrow bandwidth" patented technology

Wideband / multiband add-on metasurface modules for enhanced noise suppression in server infrastructure

The technology described herein is directed towards modular metasurfaces arranged with unit cells for narrowband, wideband and / or multiband sound absorption, in which the unit cells are based on Helmholtz resonators that are deployed in a server rack, proximate to a server, without substantially obstructing airflow from the server fan(s). Each sound absorbing unit-cells is designed and constructed based on a specific resonance frequency, and includes a neck portion and air chamber dimensioned to resonate at the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. Differently-dimensioned unit cells can be built into a single metasurface module, thereby facilitating wideband and / or multiband sound absorption with that metasurface. The modular metasurfaces can be attached to the sidewalls of a server rack, or positioned in otherwise empty slots above and below a server, optionally coupled to blanking panels for covering the openings of those slots.
Owner:DELL PROD LP

Asymmetric transmission optical device, test method and electronic device

The invention relates to an asymmetric transmission optical device, a test method and an electronic device, and belongs to the technical field of nano optics and photonics. Comprising a dielectric nano-particle array which comprises a plurality of dielectric nano-particles, and the dielectric nano-particles are periodically arranged according to a preset interval; wherein the height of the dielectric nano particles is 60 nm to 150 nm; and the dielectric substrate is arranged below the dielectric nanoparticle array. The test method comprises the following steps: establishing a periodic array model according to the optical device, and setting structural parameters of the model to obtain an optimal periodic array model; performing asymmetric transmission mechanism analysis and structural parameter analysis by using the optimal periodic array model; and according to an analysis result, obtaining an optimal structure parameter of asymmetric transmission. The problems of high loss, narrow bandwidth and polarization sensitivity are avoided, and the defects of high preparation difficulty, high cost and poor compatibility caused by a complex geometric structure or a specific material are overcome.
Owner:SUZHOU VOCATIONAL UNIVERSITY (SUZHOU OPEN UNIVERSITY)

SSPP-based negative group delay system

The invention discloses a negative group delay system based on SSPP, and belongs to the technical field of microwave communication. A fundamental mode negative group velocity is innovatively generated based on an artificial surface plasmon SSPP, and an SSPP system with negative group delay is realized. The system comprises two parts, namely an amplifier circuit and an SSPP waveguide with a negative group delay unit. The SSPP waveguide with the negative group delay characteristic comprises two coplanar waveguide parts, two transition parts and an SSPP waveguide part, the SSPP waveguide part comprises a unit for generating negative group velocity and a plurality of basic units, and further comprises a microwave dielectric substrate. The amplifier is composed of an amplifier chip, a peripheral capacitor inductor of the amplifier chip and a direct-current power supply. An input signal passes through the system, and advanced transmission of the signal can be realized. The problems of narrow bandwidth, large loss and non-adjustable structure in the prior art are effectively solved, and the antenna has wide application prospects in the fields of 5G communication, radar signal processing, array antenna systems and the like.
Owner:XIAMEN UNIV +1

Super-large octave wave absorber based on photoconductive material

PendingCN120262034AMagnetic/electric field screeningAntennasCapacitanceOctave bandwidth
The invention discloses an ultra-large octave wave absorber based on a photoconductive material, and belongs to the field of electromagnetic metasurfaces and metamaterials. Comprising a light response wave-absorbing metasurface and a light driving module capable of projecting different patterns on the surface of the light response wave-absorbing metasurface, array wave-absorbing units of different sizes are obtained on the light response wave-absorbing metasurface by switching the projected patterns, and impedance of a target frequency band is matched by changing equivalent capacitance / inductance of a wave-absorbing unit structure; the light driving module can project a preset light pattern on the light response wave-absorbing metasurface, so that the equivalent impedance distribution of the light response wave-absorbing metasurface is changed; according to the light response wave-absorbing metasurface, the conductivity distribution of the metasurface units is changed through light control, and the wave-absorbing frequency band is adjusted in real time, that is, dynamic adjustment of the wave-absorbing performance is achieved through non-contact light control. According to the invention, the limitation of narrow bandwidth and passive fixation of a traditional wave absorber is broken through, and electromagnetic wave control with ultra-large octave, high absorptivity and real-time reconfigurability is realized.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Lithographic apparatus, metrology systems, illumination switches and methods thereof

A system includes an illumination system, an optical element, a switching element and a detector. The illumination system includes a broadband light source that generates a beam of radiation. The dispersive optical element receives the beam of radiation and generates a plurality of light beams having a narrower bandwidth than the broadband light source. The optical switch receives the plurality of light 5 beams and transmits each one of the plurality of light beams to a respective one of a plurality of alignment sensor of a sensor array. The detector receives radiation returning from the sensor array and to generate a measurement signal based on the received radiation.
Owner:ASML NETHERLANDS BV +1

Video monitoring data transmission and storage method based on narrow bandwidth

The invention relates to the technical field of video compression, in particular to a narrow-bandwidth-based video monitoring data transmission and storage method, which comprises the following steps of: for an input video monitoring data frame, calculating a difference absolute value sum between a current frame and a reference frame; according to the method, the pixel difference of the current frame and the reference frame is calculated, and the average amplitude of the motion vector field is fused to form a comprehensive index of the dynamic degree of the quantized content, so that the image group structure is not fixed or periodic any more, and the dynamic degree of the quantized content can be calculated according to the score of scene activity and the change intensity. When a monitoring picture is static, a super-long image group is established to limit a compression code rate, when the picture is suddenly changed, the super-long image group is quickly switched to a short image group to ensure instant refreshing and definition of key information, meanwhile, non-uniform redistribution is performed on limited total code rate budget, bit resources can be intelligently inclined to frames with violent content change and large information amount, and the real-time refreshing and definition of the key information are ensured. Therefore, the subjective visual quality of the key dynamic moments is improved under the narrow bandwidth.
Owner:THE FIRST MONITORING AND APPLICATION CENTER CHINA EARTHQUAKE ADMINISTRATION +1

Method for correcting vibration condition of crawler running at constant speed on land

The invention belongs to the technical field of vibration conditions, and particularly relates to a crawler land constant-speed driving vibration condition correction method, crawler land constant-speed driving vibration data is often regarded as a whole to be processed as a random vibration condition to guide design and examination of parts on a vehicle, and an induction result is usually in a narrow-band + wide-band random form. However, when the crawler runs at a constant speed on the land, the frequency domain characteristic of the vibration data is closer to the form of'sine + broadband random ', and the method is suitable for correction of such vibration conditions. The accuracy of the vibration condition is improved, vibration environment distortion caused by discomfort of the induction method is reduced, and over-test or under-test of the induction vibration test is avoided. According to the invention, the narrowband component in the vibration signal is regarded as the projection of the sinusoidal signal in the power spectral density, the center frequency and the relative amplitude of the narrowband signal are calculated and converted into the frequency and the amplitude of the sinusoidal signal, and the narrowband component is replaced by the sinusoidal component, so that more accurate vibration test conditions are obtained.
Owner:XIAN MODERN CONTROL TECH RES INST

Generating device capable of generating ultra-flat broadband micro comb

The invention discloses a generating device capable of generating an ultra-flat broadband micro comb. The generating device comprises a pump pulse generating module, a micro comb generating module and a micro comb generating module, the pumping pulse compression module is connected with the pumping pulse generation module; the high-Q-value microcavity module is connected with the pumping pulse compression module; and the micro comb detection and feedback module is respectively connected with the high-Q-value micro-cavity module and the pump pulse generation module, and is used for monitoring the output spectrum and power change of the high-Q-value micro-cavity module and adjusting the output wavelength of the picosecond pulse light according to the output spectrum and power change so as to stabilize the ultra-flat broadband micro comb. By arranging the high-Q-value micro-cavity, the spectral bandwidth of the micro-comb can be effectively expanded, and the ultra-flat broadband micro-comb is output; meanwhile, the defects that the hyperbolic secant single soliton micro-comb is poor in flatness and narrow in bandwidth are overcome, and the micro-comb has obvious advantages in the application field with high requirements for the flatness and the spectral bandwidth at the same time.
Owner:SHANGHAI RADIO EQUIP RES INST

Narrowband-broadband intelligent switching method of radar

The invention discloses a narrowband-broadband intelligent switching method of a radar, and belongs to the field of radar signal processing. Single radar wide-narrow band function integration is achieved through resource multiplexing, self-adaptive triggering and dynamic parameter configuration, detection tracking in a default narrow band mode is achieved, switching is triggered based on manual instructions and double thresholds, hardware such as a common antenna and a T / R assembly is reconstructed through time division multiplexing and software parameters, the signal synchronization time is shortened, and the target tracking response delay time is shortened; double-radar collaborative design is not needed, and the design workload is reduced. According to the invention, double radars are combined into a single radar, the hardware cost is greatly reduced, and the method is suitable for unmanned aerial vehicle-mounted, vehicle-mounted and other space-limited scenes and military reconnaissance, civil security and protection and other tasks.
Owner:JIANGSU NORTH ELECTRONIC CO LTD

Bulk acoustic wave resonator with double-layer piezoelectric film structure, preparation method and filter

The invention relates to the field of microelectronic devices, in particular to a bulk acoustic wave resonator with a double-layer piezoelectric film structure, a preparation method and a filter, the bulk acoustic wave resonator comprises a cap wafer, and a dry film, a passivation layer, a silicon oxide layer, a high-resistance silicon wafer and RDL metal are sequentially arranged on the cap wafer; the dry film and the cap wafer form a dry film cavity, the passivation layer located above the dry film cavity extends into the dry film cavity, and a top electrode, a first piezoelectric film, a middle electrode, a second piezoelectric film and a bottom electrode are sequentially arranged on the passivation layer; the top electrode and the bottom electrode are used as first ports of the resonator; and the middle electrode is a second port. According to the resonator, the excitation mode of the resonator is changed through cooperation of the two layers of piezoelectric films with the same polarization direction and the intermediate electrode, a high-order resonance mode is jointly excited, meanwhile, a high electromechanical coupling coefficient is kept, and a wide fractional bandwidth is achieved at high frequency through the relatively thick piezoelectric films; the problems that a high-frequency resonator is weak in power bearing capacity, narrow in bandwidth, low in quality factor and poor in stability are solved.
Owner:XI AN JIAOTONG UNIV

Sub-wavelength structural unit and preparation method thereof, reflective array and broadband planar film antenna

The invention provides a sub-wavelength structure unit and a preparation method thereof, a reflective array and a broadband planar film antenna, and the sub-wavelength structure unit comprises a sub-wavelength structure, a metal reflective layer, a first film and a second film. The sub-wavelength structure comprises at least two types of single resonant structures; the at least two types of single resonance structures are arranged on the first thin film; the metal reflecting layer is arranged on the second thin film; a spacing layer is arranged between the first film and the second film; and the phase and dispersion characteristics of the sub-wavelength structure unit in the first resonance area and / or the second resonance area are determined by setting parameters of the single resonance structure. According to the invention, the sub-wavelength structure comprises multiple types of single-resonant structures for forming different multi-resonant sub-wavelength structures, so that the problem of narrow bandwidth of a single-layer film antenna formed by the sub-wavelength structure unit can be solved.
Owner:INST OF OPTICS & ELECTRONICS CHINESE ACAD OF SCI

System and method of monitoring a drainage network

The invention provides a drainage network monitoring system. The system comprises a sensing module for detecting one or more conditions at a location in the drainage network; a processing module for processing data received from the sensing module; a wireless communications module for communicating the processed data substantially in real-time to one or more wireless devices including a wireless notification device configured to issue notification information to users, wherein the wireless communications module utilizes a narrow bandwidth, low power wireless communications protocol to communicate processed data to the wireless notification device, and wherein the sensing module has a standalone power supply.
Owner:LOGISTICS & SUPPLY CHAIN MULTITECH R&D CENT LTD

Broadband filtering device and multi-system access platform

The invention provides a broadband filtering device and a multi-system access platform, and relates to the technical field of multi-system access platforms, and the broadband filtering device comprises a dielectric substrate; the resonator is arranged on the surface of the dielectric substrate; and the plurality of input units are wound on the resonator, each input unit comprises a first coupling line, a second coupling line and an input piece which are arranged on the surface of the dielectric substrate, the first coupling line and the second coupling line are connected with the input piece, the first coupling line and the second coupling line are coupled with the resonator, and the input piece is used for inputting an electric signal. According to the broadband filtering device and the multi-system access platform provided by the invention, the problem that the bandwidth is relatively narrow when a filtering device works in the prior art is solved.
Owner:ZHONGTIAN COMM TECH CO LTD +2

Ultra-large octave antenna based on organic photoconductive material

The invention discloses an ultra-large octave antenna based on an organic photoconductive material, and belongs to the field of metamaterials and antennas. Comprising an organic photoconductor film electromagnetic surface and a digital light processing module capable of projecting different patterns on the surface of the organic photoconductor film electromagnetic surface, the organic photoconductor film electromagnetic surface can change conductivity distribution through light control, and the digital light processing module can dynamically adjust the size and shape of the patterns projected on the organic photoconductor film electromagnetic surface. Therefore, a reconfigurable antenna array is generated, and cross-multi-octave ultra-wideband electromagnetic wave signal receiving and transmitting are realized. The electromagnetic surface of the organic photoconductor film sequentially comprises a photoconductive material layer, a first light-transmitting glass layer, an indium tin oxide microstrip line feed layer, a second light-transmitting glass layer and a substrate indium tin oxide layer according to a lamination sequence. According to the invention, the problems of narrow bandwidth, slow response and high cost of a traditional reconfigurable antenna are solved.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Multispectral compatible camouflage and radiant heat management device and multispectral camouflage system based on same

The invention discloses a multispectral compatible camouflage and radiant heat management device and a multispectral camouflage system based on the same, relates to the field of multispectral camouflage materials and heat management, and aims to solve the problems of poor spectrum compatibility, narrow bandwidth, insufficient heat management and high angle sensitivity in the prior art. A phase change material layer is arranged on the metal substrate layer, and a phase regulation and control layer of a chessboard structure is arranged on the phase change material layer. According to the invention, the radar scattering cross section is large, the specular reflectance is very low, the performance can still be maintained in the incidence angle range of 0-30 degrees, the reflectance is not sensitive to the incidence angle and the polarization state, laser stealth, radar stealth and infrared camouflage can be realized, the spectrum compatibility is good, the bandwidth is wide, dynamic heat dissipation in a non-window can be realized, and the performance is stable. And the heat management effect is achieved.
Owner:HENAN NORMAL UNIV

Bent channel-Helmholtz composite low-frequency broadband sound absorber and design method thereof

The invention discloses a bent channel-Helmholtz composite low-frequency broadband sound absorber and a design method thereof. The sound absorber is formed by connecting a plurality of bent channel metamaterial sound absorption units around a Helmholtz resonator unit in parallel in a coupling mode. By controlling the impedance of the Helmholtz neck and the impedance of the bending channel, each unit is in an under-loss state, and then the overall critical coupling is realized by utilizing the area coupling effect, so that the sound absorber has the sound absorption coefficient of more than or equal to 0.5 in the frequency band of 267-382Hz under the thickness of 35mm. According to the sound absorber, broadband efficient sound absorption is achieved through impedance coupling of the Helmholtz resonators and the bent channels, the problems that a traditional structure is narrow in frequency band, difficult to regulate and control and the like are solved, and theoretical and technical supports are provided for low-frequency noise control.
Owner:JIANGSU UNIV OF SCI & TECH

Audio noise reduction method and system based on Polar code transmission

The invention relates to the technical field of audio noise reduction, and discloses an audio noise reduction method and system based on Polar code transmission, and the method comprises the steps: firstly obtaining an original audio signal, extracting an audio feature vector of the original audio signal, carrying out the suppression of a noise component in a feature domain, and obtaining an audio feature vector sequence after noise reduction; and feature coding and quantization are carried out on the feature sequence, and the feature sequence is converted into a bit stream with a compact structure so as to adapt to the narrow bandwidth and efficient transmission requirements of a wireless channel. In the channel coding stage, the high error correction capability and the polarization characteristic of the Polar code are fully utilized, the characteristic bit stream is effectively coded, and the anti-interference performance and the transmission robustness of the audio data in the severe wireless environment are greatly improved. And finally, mapping the bit stream after Polar coding into a modulation symbol, completing conversion to an analog radio frequency signal, and realizing high-quality wireless noise reduction transmission of an audio signal. Therefore, not only is the audio transmission quality improved, but also the reliability of data transmission is ensured.
Owner:WUHAN PANSHENG DINGCHENG TECH CO LTD

Terahertz biological tissue imaging system and imaging method based on metasurface antenna

The application discloses a terahertz biological tissue imaging system and method based on a metasurface antenna. The terahertz biological tissue imaging system comprises a terahertz signal generator, an intelligent system control device, a terahertz signal transmitter and a data acquisition module. The terahertz signal generator is used for generating an ultra-wideband terahertz wave signal. The intelligent system control device controls the terahertz signal generator to continuously generate the ultra-wideband terahertz wave signal. The terahertz signal transmitter is used for transmitting the ultra-wideband terahertz wave signal after programmable modulation to a biological tissue organ. The terahertz signal receiver is used for receiving terahertz biological signals scattered inside and around the biological tissue organ, and modulating the received terahertz biological signals. The data acquisition module is used for acquiring the terahertz biological signals. The intelligent sensing signal processing module is used for processing the terahertz biological signals to obtain a terahertz image of the biological tissue organ. The application solves the problems of narrow bandwidth and low gain in the corresponding technology.
Owner:SHENZHEN TECH UNIV

Angle-adjustable narrow-band heat radiator based on corner hyperbolic phonon polaritons

The invention discloses an angle-adjustable narrow-band heat radiator based on corner hyperbolic phonon polaritons. The heat radiator sequentially comprises a metal layer, a natural biaxial hyperbolic medium, a vacuum / air spacing layer and a one-dimensional medium grating. According to the angle-adjustable heat radiator, the biaxial hyperbolic medium and the gold layer are twisted as a whole, and the included angle between the radiating surface and the plane where the crystal axis of the natural biaxial hyperbolic medium is located is changed, so that the heat radiation direction is changed. The radiator can be produced on a large scale at low cost by utilizing processes such as nano photoetching and deposition. The narrow-band directional thermal radiation device obtained through the nano manufacturing technology is stable and reliable in performance, can generate thermal radiation with narrow bandwidth and small radiation angle, has the characteristics of adjustable direction, flexibility, convenience and the like, and is expected to be applied to the fields of directional heat dissipation, thermal camouflage and the like.
Owner:ZHEJIANG UNIV

Method, device and storage medium for security authentication encryption in initial stage of communication link establishment

The application discloses a kind of communication link establishment initial stage security authentication encryption method, device and storage medium, the present application is limited to narrow bandwidth for end-to-end wireless communication link establishment, cannot apply conventional encryption preparation, it is difficult to guarantee that preset symmetric key is added after planning, abandon password protection is also prone to be maliciously controlled and so on Problem, an authentication encryption adaptive method based on pre-stored and diffusion key is proposed, by making full use of the key storage space of end device pre-stored key, supplemented by the diffusion transmission of new key with the process of link establishment, combined with the two modes of offline preset loading when opening and automatic online interaction after new communication terminal joins interworking, under the premise of no manual participation, maximum reduction to the occupation of link establishment narrow band, the security of information transmission is greatly improved, so as to improve user experience.
Owner:NO 30 INST OF CHINA ELECTRONIC TECH GRP CORP

Dual-channel optical filter based on three-rectangular-cavity edge coupling waveguide

ActiveCN224216907ULarge transmittance contrastImprove filtering effectOptical light guidesWaveguideFilter effect
The utility model relates to a dual-channel optical filter based on a three-rectangular cavity edge coupling waveguide. The dual-channel optical filter comprises a silicon substrate, a sapphire layer, a graphene nano-strip waveguide, a first graphene rectangular resonant cavity, a second graphene rectangular resonant cavity and a third graphene rectangular resonant cavity, the sapphire layer is arranged above the silicon substrate; a graphene nano-strip waveguide, a first graphene rectangular resonant cavity, a second graphene rectangular resonant cavity and a third graphene rectangular resonant cavity are arranged on the upper surface of the sapphire layer; the first graphene rectangular resonant cavity and the third graphene rectangular resonant cavity are connected in series and arranged on one side of the graphene nano-strip waveguide, and the second graphene rectangular resonant cavity is arranged on the other side of the graphene nano-strip waveguide. According to the utility model, the problems of narrow bandwidth and poor filtering effect of an optical filter with a graphene structure are solved; the dual-channel optical filter which is small in size, wide in bandwidth, excellent in filtering effect, dynamically tunable and easy to integrate is realized in an infrared band.
Owner:HUBEI ENG UNIV

Resource data sensing method and device and communication equipment

The invention belongs to the technical field of communication, and particularly relates to a resource data sensing method and device and communication equipment, and the resource data sensing method comprises the steps that a sensing node collects multi-dimensional environment parameters and generates environment feature vectors, and a current interference type is recognized based on an interference classification model; according to the identified interference type, selecting an anti-interference algorithm combination corresponding to the first order from an anti-interference strategy library; adjusting a sensing parameter based on a dynamic parameter in the environment feature vector, and collecting and preprocessing target resource data to obtain noise-reduced resource data; evaluating the confidence coefficient of the denoised resource data, and if the confidence coefficient reaches the standard, outputting the resource data; if the confidence degree does not reach the standard, strategy iteration is triggered until resource data with the confidence degree reaching the standard are output, the method can adapt to diversified interference of narrow bands, wide bands and the like, matching of interference types and anti-interference strategies is achieved, interference is restrained to the maximum extent, the data distortion rate in the complex environment is reduced, and high-reliability data support is provided for resource scheduling.
Owner:STATE GRID CORPORATION OF CHINA +2

Uplink data communication in narrow bandwidth data communication bandwidth portion

A user equipment (UE) may be configured to utilize a narrow bandwidth data communication bandwidth portion for data communication. A conventional technology for interleaving virtual resource blocks (RBs) to physical RB mapping is not enough. For example, a conventional interleaving virtual RB to physical RB mapping is based in part on the size of an active bandwidth portion, and RBs are interleaved throughout the active bandwidth portion. However, for a narrow bandwidth data communication bandwidth portion, communication is not supported outside a particular narrow bandwidth portion. The conventional interleaving virtual RB-to-physical RB mapping may cause some virtual RBs to map to physical RBs that are at least partially outside of the narrow bandwidth data communication bandwidth portion, and thus the conventional interleaving virtual RB-to-physical RB mapping should not be utilized for an interleaving virtual RB-to-physical RB mapping over the narrow bandwidth data communication bandwidth portion.
Owner:QUALCOMM INC

Transmission of resource units by narrow bandwidth operating devices in wide bandwidth spectrum

This disclosure provides methods, components, devices and systems for transmission of resource units by narrow bandwidth operating devices in wide bandwidth spectrum. A station (STA) may identify or receive a resource unit (RU) allocation including a global RU index for a wide bandwidth. The STA may translate the global RU index into a local RU index for a local tone plan, may map the assigned RU to distributed RU (dRU) tones over a corresponding distribution bandwidth, and may shift the mapped dRU tones to align with the wide bandwidth. The STA also may support transmission of short training fields (STFs) and long training fields (LTFs) using a similar mapping and shifting, or using tones of the wide bandwidth that fall within the distribution bandwidth region. A STA also may support a tone plan splitting a wide bandwidth into segments of the distribution bandwidth to allow direct mapping.
Owner:QUALCOMM INC

Temperature-adjustable OCM or TOF

The utility model relates to a temperature adjustable OCM or TOF, comprising two oppositely arranged optical fiber collimators, an ultra-thin etalon and a silicon-based etalon are sequentially arranged between the two optical fiber collimators, the ultra-thin etalon is formed by plating a-Si, SiH or GeH film on a silicon substrate, and the silicon-based etalon is formed by plating a-Si, SiH or GeH film on the silicon substrate. The ultra-thin etalon and the silicon-based etalon are respectively connected with a temperature controller for adjusting the temperatures of the ultra-thin etalon and the silicon-based etalon; the line width of the ultra-thin etalon is smaller than the free spectral range of the silicon-based etalon, and the line width top of the ultra-thin etalon is always and synchronously sleeved above one transmission wavelength of the silicon-based etalon along with the temperature change; when pulse or quasi-pulse is used for rapid adjustment, the OCM is used as a high-resolution OCM; during low-speed adjustment, the TOF serves as a narrow or ultra-narrow bandwidth TOF. According to the utility model, the advantages of both the film-coated etalon and the silicon-based etalon are combined, and the degree of freedom is higher.
Owner:SHANGHAI BRANCH FUZHOU GAOYI COMM CO LTD

A microwave photon frequency hopping signal generation device and method based on an optical switch

The application discloses a microwave photon frequency hopping signal generation device and method based on an optical switch and belongs to the technical field of optical communication. The application is composed of a light source, a beam splitter, an optical frequency comb generator, an electro-optical frequency shifter, an acousto-optic modulator, a digital frequency synthesizer, a filter array, a signal control unit, an electrically controlled high-speed optical switch, a beam combiner and a photoelectric detector. The application separates optical frequency comb teeth by using an ultra-narrow bandwidth optical filter, selects and opens the frequency hopping signal generated by the local light beat frequency through the optical switch, and can generate a high-speed high-order high-stability frequency hopping signal compared with the prior art.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION +1

Methods, apparatus and computer programs

A user equipment comprising: means for detecting one or more synchronisation signals on a synchronisation raster point of a first synchronisation raster and when a synchronisation signal is not detected, searching for one or more synchronisation signals on another synchronisation raster point of the first synchronisation raster, the first synchronisation raster being associated with a first synchronisation signal and physical broadcast channel configuration having a relatively narrow bandwidth compared to a second synchronisation signal and physical broadcast channel configuration which is associated with a second different synchronization raster, one or more synchronisation signals of the first synchronisation signal and physical broadcast channel configuration being associated with a first sequence length and one or more synchronisation signals of the second synchronisation signal and physical broadcast channel configuration being associated with a second different sequence length; means for detecting one or more master information blocks of a first physical broadcast channel associated with the one or more synchronisation signals, when the one or more synchronisation signals are detected; and means for performing an initial access of a cell associated with the first physical broadcast channel.
Owner:NOKIA TECHNOLOGIES OY

A single-fed broadband circularly polarized patch antenna for navigation

A single-feed broadband circularly polarized patch antenna for navigation provided by the present invention comprises a first dielectric plate, a second dielectric plate, a third dielectric plate, a metal shielding box and a coaxial cable; an antenna radiator is printed on the first dielectric plate, a coplanar waveguide structure is printed on the second dielectric plate, and a feeding structure is printed on the third dielectric plate; the coaxial cable feeds power to the coplanar waveguide structure on the second dielectric plate through the feeding structure on the third dielectric plate; and the coplanar waveguide structure on the second dielectric plate couples and feeds power to the antenna radiator on the first dielectric plate. The present invention combines a coplanar waveguide structure with a patch antenna, and through a coplanar waveguide coupling feeding technique, successfully improves the axial ratio bandwidth of the single-feed circularly polarized antenna, doubles the maximum operating bandwidth of the single-feed circularly polarized antenna, solves the problem that it is difficult to apply the single-feed circularly polarized antenna with a narrow bandwidth to satellite navigation, and has extremely high applicability and flexibility in the satellite navigation applications of multiple systems and multiple frequency bands.
Owner:GUANGDONG UNIV OF TECH

NB-IoT-oriented internet of things sensor data encryption transmission method

This invention discloses a method for encrypted transmission of IoT sensor data for NB-IoT, relating to the fields of IoT communication and information security technology. The invention constructs an association mapping relationship between wireless channel coverage enhancement level, transport block size index, transport block bit length, and number of repeated transmissions, and matches the optimal transport block configuration by combining transmission resource overhead budget. Based on channel state and transmission capacity, it performs adaptive encryption and data compression processing, generates implicit random numbers, and completes data encapsulation. Stable transmission of the encapsulated data is achieved through the narrow bandwidth channel of NB-IoT, and consistency verification is performed at the receiving end. This effectively solves the problems of poor adaptability and high transmission overhead of traditional encryption schemes, improving the security, efficiency, and reliability of IoT sensor data transmission.
Owner:HEFEI XINLI TECH CO LTD

Quantum key distribution system and method capable of tolerating high-noise link

The invention discloses a quantum key distribution system and method capable of tolerating a high-noise link, and the method comprises the steps: carrying out the specific ultra-narrow bandwidth configuration in a transmitting terminal and a receiving terminal of QKD equipment at the same time; in this way, the capability of tolerating a high-noise link can be provided for a QKD system especially under the scene that classic optical communication equipment and QKD equipment have a small wavelength interval of 25GHz or an integral multiple of 25GHz, and the power of a classic optical signal does not need to be lowered or the classic optical signal and a quantum optical signal do not need to be configured on two wavebands with a large interval to reduce noise. The power and the wavelength of classical optical communication equipment do not need to be limited too much, practical engineering application can be greatly facilitated, the quantum optical signals and the classical optical signals can achieve small link attenuation at the same time, and the method is suitable for long-distance scenes.
Owner:QUANTUMCTEK CO LTD