19 results about "Maximum gain" patented technology

An aircraft radome and radar assembly includes: a radome arranged on the nose of the aircraft; a radar inside the radome, the radar operating in the millimeter domain and including a transmission antenna for emitting a TM polarized wave and a reception antenna; the radome includes an integrated window in front of the radar, the window being of a material transparent to millimeter waves; the radar being arranged so the angle between the maximum gain direction of the transmission antenna and the normal to the window is within an angular range [θB−θ1; θB+θ2], with OB being the Brewster angle for an air / window interface, θ1 and θ2 determined to obtain reflectivity at said air / window interface less than a predefined threshold; and an isolation partition between the transmission antenna and the reception antenna, the isolation partition being substantially in contact with the window and with the radar.

The application discloses a large-aperture array antenna subarray structure adjustment method facing electrical performance, and comprises the following steps: S1, determining maximum gain loss; S2, establishing sensitivity distribution matrix; S3, calculating position tolerance distribution weight; S4, giving initial installation tolerance standard; S5, calculating position tolerance distribution matrix; S6, generating position error random sample; S7, calculating antenna electrical performance; S8, judging whether the position error random sample meets the requirement; S9, calculating new position tolerance standard; and S10, calculating maximum allowed structure adjustment amount. The application can realize the target of taking antenna electrical performance as the target, quantitatively giving the subarray structure adjustment amount of different regions of a large-aperture array antenna, strictly requiring the structure precision of the subarray in the region with high electrical performance sensitivity, appropriately reducing the structure precision requirement in the region with low electrical performance sensitivity, reducing the processing and manufacturing difficulty of the large-aperture array surface, improving the adjustment efficiency of the large-aperture array antenna, and guaranteeing the high performance of the array antenna.

The present application relates to the technical field of optical communications, and specifically relates to an adaptive control method and system for a transmitter gain of an LPO optical module, and an optical module. The method comprises the following steps: acquiring a maximum gain peak value and an output amplitude acquisition value of an LPO optical module state machine in a normal operating state; performing fitting calculation on the basis of the output amplitude acquisition value and a peak value control look-up table to determine a comprehensive output amplitude; comparing the comprehensive output amplitude with a target gain; and optical module firmware adaptively adjusting the transmitter gain of an LPO optical module on the basis of a comparison result and by considering the maximum gain peak value. In the present application, different switch ports and different high and low temperature environments can be adaptively matched, so that the matching efficiency between an LPO optical module and a switch can be effectively improved, thereby reducing unnecessary labor construction costs and maintenance costs of an application end and various errors and deviations caused by manual debugging.

The invention discloses a large-scale MIMO beam training method and device, and the method comprises the steps: constructing a shared training system composed of a basic DFT codebook, a frequently repeated code target response matrix and a corresponding combined coding codebook, and carrying out the maximum posteriori decoding based on an energy observation sequence, thereby enabling the maximum posteriori decoding to be carried out under the time delay constraint condition that the number of training rounds is limited, and achieving the maximum posteriori decoding. And the beam forming vector with the maximum gain can still be accurately selected at a high probability. Compared with a traditional exhaustive search method, the inquiry frequency of beam training is remarkably reduced; compared with binary search and convolutional coding search schemes, the decoding accuracy is improved under the same number of training rounds, so that beam training performance improvement with low time delay and high accuracy considered is realized.

The application discloses a beamforming method of a holographic MIMO antenna array based on a steering vector, and under the condition that a user end position is unknown, multiple code words are constructed based on the steering vector through the combination of the pitch angle and the azimuth angle of the user end relative to the antenna array, a code word with the maximum gain of a receiving end is selected from the code words according to the feedback of the user end, and the code word is used as the optimal transmitting or receiving coefficient of the antenna array. The user end only needs to feed back the corresponding information in sequence, the requirement for the feedback time delay is slightly low, the error code of the feedback information has a certain fault tolerance, the time complexity is relatively low compared with the exhaustive search method, the performance is good, the outdoor channel changing rapidly can be well responded, the robustness to the channel fluctuation is higher, and the overall power gain is improved. Moreover, under the condition that the user end position is known, the transmitting or receiving coefficient of the antenna array can be directly determined.

Aircraft Radome and Radar Assembly The invention relates to an aircraft radome and radar assembly (EAR) comprising: a radome (Rd) disposed on the nose of the aircraft (NA); a radar (Ra), disposed inside the radome (Rd), the radar (Ra) being configured to operate in the millimeter range and comprising a transmitting antenna (Tx) configured to emit a TM polarized wave and a receiving antenna (Rx); the radome (Ra) comprising a window (F) integrated in said radome, the window (F) being in a material transparent to millimeter waves, the window (F) being opposite the radar (Ra); the radar (Ra) being disposed such that the angle (θi) between the maximum gain direction (DGM) of the transmitting antenna (Tx) and the normal (N) to the window (F) is within an angular range [θB - θ1;θB + θ2], with θB being the Brewster angle for an air / window interface, θ1 and θ2 determined to obtain a reflectivity at said air / window interface below a predefined threshold; and an isolation partition (IC) disposed between the transmitting antenna (Tx) and the receiving antenna (Rx), the isolation partition (IC) being substantially in contact with the window (F) and with the radar (Ra). Figure for the abstract: Fig. 1;

The application provides a broadband high-gain metasurface antenna and array for a millimeter wave vehicle-mounted radar, comprising, from top to bottom, an air cavity dielectric substrate, a metasurface layer, a substrate patch, an upper layer dielectric substrate, a ground layer, a lower layer dielectric substrate and a feed line layer, wherein the metasurface layer is a metasurface patch group composed of 3*3 square patches, a center square patch located at the center position of the metasurface patch group is provided with a slot at the center, corner square patches located at the four corner positions of the metasurface patch group are provided with cut corners at the corners, and peripheral square patches located at the upper, lower, left and right positions of the center square patch are provided with grooves at the outer periphery; wherein the substrate patch is a substrate patch group composed of two rectangular patches arranged at intervals, the substrate patch group is arranged opposite to the metasurface patch group, has a super wideband performance of more than 650 MHz, a maximum gain greater than 6 dBi, and a radiation efficiency of more than 75%.

This invention discloses a low-profile horizontal omnidirectional scanning antenna, comprising a dielectric substrate, a central feed unit disposed on the upper and lower surfaces of the dielectric substrate, a ring-shaped parasitic unit composed of six arc-shaped patches placed around the central feed unit on the lower surface of the dielectric substrate, and six corresponding bias circuits. Each of the six arc-shaped patches of the parasitic unit is equally divided into two sub-arc-shaped patches, which are connected by pin diodes. The bias circuits consist of two inductors and two microstrip lines, used to control the state of the pin diodes. A directional mode is achieved by controlling two reverse-biased and four forward-biased pin diodes; when all diodes are forward-biased, it is in omnidirectional mode. When in directional mode, the antenna operates at 2.478 GHz, can achieve 360° beam switching, has a maximum gain of 7.44 dBi, and a minimum S11 of -27 dB.

The application discloses a method for correcting deflection of an antenna radiation beam under a radome based on time reversal, and belongs to the technical field of radars. The method is used for processing signals received by each array element in an array antenna by using the time reversal method, and re-emitting the processed time reversal signals from the corresponding array element, so that more accurate beam pointing is achieved, and the aiming error is reduced. Based on the time reversal technology, the application can realize the effect of adaptive direction backtracking, and ensure that the target angle has the maximum gain under the target frequency; compared with a traditional phased array feeding method under the radome, the method has a better aiming error index.

The utility model discloses a Ka frequency range antenna, belongs to the technical field of communication, and comprises 256 unit horn array antennas and an antenna carrier plate, and belongs to the field of antenna design, the unit horn array antennas are uniformly distributed on the antenna carrier plate, the spacing of the unit horn array antennas is 18.5 mm, the size of the antenna carrier plate is 300mm * 300mm * 40mm, and the antenna carrier plate is a rectangular plate. According to the utility model, the technical problems in the prior art that the maximum gain of the antenna is too small and the circular polarization axial ratio is too large are solved.

The application provides a dynamic equalization method and circuit, which comprises the following steps: calculating a maximum gain coefficient and a minimum gain coefficient according to an input signal and preset processing parameters; multiplying the filtered input signal and one of the maximum gain coefficient and the minimum gain coefficient to obtain a first output signal; multiplying the input signal directly or after filtering or delaying and the other of the maximum gain coefficient and the minimum gain coefficient to obtain a second output signal; and superimposing the first output signal and the second output signal to obtain a final output signal; and adjusting the proportional relationship between the two input signals to achieve the purpose of adjusting the final output signal in real time. This method simplifies the required calculation amount and storage space of the dynamic filter, avoids the problem of harmonic and noise caused by the sudden change of the filter coefficient, and is effective in optimizing the calculation amount.

This invention discloses a Ka-band high-gain broadband microstrip patch antenna, primarily addressing the challenges of existing Ka-band antennas in simultaneously achieving broadband bandwidth and high gain, as well as their complex structures. It employs a stacked structure of a double-layer dielectric substrate, comprising, from top to bottom, a radiating patch, a first dielectric substrate, a metal ground plane, a second dielectric substrate, and a microstrip feed line. The radiating patch is a butterfly-like structure formed by cutting a square patch as a base and loading an anti-interference plate. A cross-shaped slot, formed by the orthogonal superposition of two identical H-shaped slots, is formed on the metal ground plane. The microstrip feed line achieves electromagnetic coupling with the radiating patch through this slot. This invention, through the coordinated design of patch and slot feeding, broadens the relative bandwidth and increases the maximum gain within the Ka-band, achieving an excellent balance between wide impedance bandwidth and high radiation gain. It also boasts advantages such as simple structure, easy fabrication, low cost, and easy integration, making it suitable for 5G millimeter-wave and satellite communication systems.

The application discloses a millimeter wave broadband antenna array of a MEFAB process, which comprises an I-shaped slotted metal floor, two pairs of mutually parallel vertical metal columns, L-shaped metal folded patches, two pairs of rounded rectangular patches and a rectangular coaxial structure; the overall profile height of the antenna is reduced by folding the L-shaped patches and cooperating with the vertical metal columns to change the current path; and a larger space is left between the horizontal rounded rectangular patches and the vertical metal columns to generate a capacitive effect, so that the matching of the antenna is realized; the I-shaped slot gap is slotted and gradually changed, so that the electric dipole and the magnetic dipole are effectively excited; and the maximum gain of the antenna unit is improved through the common radiation of the two pairs of magnetic dipoles and electric dipoles.

An OTDR-based optical cable test method: measuring an optical cable by means of the maximum test pulse width satisfying the maximum gain of the optical cable, and acquiring test curve data and a corrected event start point and an event end point of each signal change event thereon; on the basis of the corrected event start points and the event end points, acquiring a normal optical cable segment in the test curve data; fitting the test curve data to obtain the optical cable length of the optical cable; on the basis of the optical cable length, acquiring a test distance of the optical cable; and, on the basis of the normal optical cable segment, acquiring the minimum test pulse width for an optical cable test. Compared with the prior art, directly using the maximum test pulse width that can meet the maximum gain of the optical cable to measure and obtain the test curve data, which can reflect the measurement situation of the optical cable at the maximum gain, can quickly acquire at a time various parameter information that needs to be set for the test, so as to improve the accuracy and efficiency of the optical cable test. Further provided are an OTDR optical cable test system, an optical time domain reflection device, and a storage medium.

The invention discloses a multi-beam digital transmission metasurface design method adaptive to direct communication of the Internet of Vehicles. The metasurface works in a 5.9 GHz frequency band and is composed of 40 * 40 double-C-shaped slot loading units, 2-bit transmission phase coding is achieved by adjusting inner-layer slot parameters of the units, and the transmission amplitude is superior to-2dB. According to the design, a quadrant partition beam forming method is adopted, an array is divided into four sub-regions, superposition codes of a focusing phase and a specific deflection phase are loaded respectively, and therefore four symmetrically-distributed high-gain beams are synchronously generated. Simulation results show that main beams of the array respectively point to azimuth angles of 45 degrees, 135 degrees, 225 degrees and 315 degrees, pitch angles are all 30 degrees, the maximum gain reaches 14.2 dBi, the narrow-beam and low-sidelobe characteristics are achieved, and the problem of efficient coverage of one source and multiple directions in an Internet of Vehicles scene is effectively solved.

This quantum cascade laser device (500) is characterized by being provided with at least a core region (10) in which is formed a multi-layer cascade structure (40) having an active region (38) in which barrier layers and well layers are alternately formed, and an injection region (39) in which electrons are injected into the active region (38), and by having a maximum gain value at a wavelength [lambda] qcl when a current is injected. When the wavelength width between two points at which a gain value reduced to a predetermined ratio with respect to the maximum gain value is represented by [Delta] [lambda] qcl, one end surface is provided with a low-reflectance film (6) having a minimum reflectance at a wavelength [lambda] cot, which is a wavelength separated by a predetermined wavelength from the wavelength [lambda] qcl, and the other end surface is provided with a low-reflectance film (6) having a minimum reflectance at a wavelength [lambda] cot, which is a wavelength separated by the predetermined wavelength from the wavelength [lambda] qcl. When the wavelength width between two points at which a mirror loss value is generated when a preset loss value is subtracted from the maximum value of the mirror loss [alpha] mir is set as [delta] [lambda] mir, [delta] [lambda] mir is less than [delta] [lambda] qcl.

Systems, methods, and instrumentalities may be configured for coding tree unit (CTU) grid shifting. An exemplary video decoding device may receive a picture encoded based on a ratio value. The device may receive a ratio value corresponding to the picture. The device may decode the picture based on the ratio value. The ratio value may correspond to a picture corresponding to a maximum gain. Decoding the picture based on the ratio value may include decoding the picture based on the maximum gain.

This invention relates to the field of fiber optic amplification technology, and in particular to a method and apparatus for rapidly locking different gains of an EDFA (Electronic Optical Fiber Amplifier). The method includes: linearly fitting the calibration values ​​of the gain factor and ASE factor corresponding to the maximum and minimum gains within a preset gain range to obtain the gain factor and ASE factor corresponding to each gain within the preset gain range; calibrating the input light within the preset gain range to obtain the relationship between the sampled ADC value and the reported power of the input light corresponding to each gain within the preset gain range; determining the target gain, obtaining the target gain factor, target ASE factor, and target reported power corresponding to the target gain, and obtaining the target input optical power based on the target gain factor, target ASE factor, and target reported power; obtaining the pump DAC value required for the target gain based on the monitored output optical power and the target input optical power, and adjusting the drive current of the pump unit through the pump DAC value to achieve locking of the target gain.

The invention discloses a millimeter wave broadband antenna array manufactured by an MEFAB process. The millimeter wave broadband antenna array comprises an I-shaped slotted metal floor, two pairs of mutually parallel vertical metal columns, an L-shaped metal folding patch, two pairs of rounded rectangular patches and a rectangular coaxial structure, the folded L-shaped patch is matched with the vertical metal column to change a current path, so that the overall profile height of the antenna is reduced; a large space is reserved between the horizontal rounded rectangular patch and the vertical metal column to generate a capacitance effect, so that antenna matching is realized; effective excitation of the electric dipole and the magnetic dipole is realized through the I-shaped gap with the gradually-changed slot; through common radiation of the two pairs of magnetic dipoles and electric dipoles, the maximum gain of the antenna unit is improved.