126results about How to "Increase buff effect" patented technology

A power amplifier using N-way Doherty structure with adaptive bias supply power tracking for extending the efficiency region over the high peak-to-average power ratio of the multiplexing modulated signals such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. In an embodiment, the present invention uses a dual-feed distributed structure to an N-way Doherty amplifier to improve the isolation between at least one main amplifier and at least one peaking amplifier and, and also to improve both gain and efficiency performance at high output back-off power. Hybrid couplers can be used at either or both of the input and output. In at least some implementations, circuit space is also conserved due to the integration of amplification, power splitting and combining.

A power amplifier using N-way Doherty structure for extending the efficiency region over the high peak-to-average power ratio of the multiplexing modulated signals such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. In an embodiment, the present invention uses a dual-feed distributed structure to an N-way Doherty amplifier to improve the isolation between at least one main amplifier and at least one peaking amplifier and, and also to improve both gain and efficiency performance at high output back-off power. Hybrid couplers can be used at either or both of the input and output. In at least some implementations, circuit space is also conserved due to the integration of amplification, power splitting and combining.

A power amplifier using N-way Doherty structure for extending the efficiency region over the high peak-to-average power ratio of the multiplexing modulated signals such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. In an embodiment, the present invention uses a dual-feed distributed structure to an N-way Doherty amplifier to improve the isolation between at least one main amplifier and at least one peaking amplifier and, and also to improve both gain and efficiency performance at high output back-off power. Hybrid couplers can be used at either or both of the input and output. In at least some implementations, circuit space is also conserved due to the integration of amplification, power splitting and combining.

The invention discloses a forward error correction encoding, decoding method, an apparatus and a system and belongs to the communication field. The method comprises: determining check matrix parameters of LDPC recurrent code of a time varying period according to transmission system performance, complexity and codon synchronization alignmental, constructing a QC-LDPC check matrix according to determined check matrix parameters and obtaining the check matrix HC of time variant LDPC recurrent code according to the QC-LDPC check matrix; blocking to-be-encoded data according to HC requirement, encoding every blocking data based on HC and obtaining a plurality of codens of LDPC recurrent code; adding the plurality of codens of LDPC recurrent code to data frames and sending the codens of LDPC recurrent code. The invention carries out forward error correction by adopting time variant LDPC recurrent code and LDPC recurrent code has a QC-LDPC structure. Because QC-LDPC checking characters can reduce checking complexity, the performance of LDPC recurrent code is superior to the performance of LDPC block code and the performance of time variant LDPC recurrent code is superior to the performance of time invariant LDPC recurrent code, the invention can be appropriate for a high-speed optical transmission system and satisfy requirements of high gain performance and high throughput.

The invention provides a weak signal detection amplification system based on an optoelectronic oscillator and a detection amplification method thereof, and belongs to the technical field of microwavephotonics. The weak signal detection amplification system based on the optoelectronic oscillator comprises a laser, a beam splitter, a phase modulator, a high-nonlinearity optical fiber, a circulator,a photoelectric detector, a power divider, a coupler, an electric amplifier, an intensity modulator, an adjustable optical attenuator and a radio frequency source. Wherein the laser is connected withthe beam splitter, the beam splitter is respectively connected with the phase modulator and the intensity modulator, and the phase modulator, the circulator, the photoelectric detector, the power splitter, the coupler and the electric amplifier are sequentially connected end to end to form a loop; Wherein the intensity modulator, the variable optical attenuator and the circulator are sequentiallyconnected, the radio frequency source is connected to the intensity modulator, and the phase modulator is connected with the circulator through a high-nonlinearity optical fiber. By adjusting the radio frequency source and the adjustable optical attenuator, rapid and high-precision weak signal detection and amplification can be realized.

A compact multiple-frequency Z-type Inverted-F antenna includes a dielectric substrate having a horizontal axis and a vertical axis perpendicular to the horizontal axis. A feed point is disposed along the horizontal axis on a first side of the vertical axis and a ground strip is disposed along the horizontal axis on a second side of the vertical axis opposite the feed point. A plurality of wedge-shaped radiating traces is arranged symmetrically with respect to the horizontal axis and disposed on the first side of the vertical axis. A plurality of wedge-shaped ground traces symmetrical to the plurality of radiating traces with respect to the vertical axis are disposed on the second side of the vertical axis.

The invention discloses a GaAs HBT high-gain broadband linear transconductance unit circuit comprising an input stage subcircuit, a basic transconductance subcircuit, a linear subcircuit, a negative resistance subcircuit and a mirror current source subcircuit, wherein the input stage subcircuit is used for level shift of input differential voltages IN_P and IN_N and conducts shifted signals into the basic transconductance subcircuit; the basic transconductance subcircuit is used for converting the input differential voltage signals into differential current signals; the linear subcircuit is used for improving the linearity of the basic transconductance subcircuit; the negative resistance subcircuit is used for improving the gain of the transconductance circuit; and the mirror current source subcircuit is used for providing bias current for the rest circuits. The circuit is designed and manufactured by a GaAs HBT technology and has wide operation bandwidth; the adopted linear subcircuit can effectively complement the nonlinearity of the circuit and provides excellent linearity; and the negative resistance subcircuit is adopted to effectively solve the conflict between the high-gainrequirement of circuits and transistor saturation and improves high-gain performance.

The invention relates to a method for amplifying two-cell Brillouin scattering by controlling a polarization state. In order to do research on the influence of the polarization state of pumping light and seed light on an SBS (stimulated Brillouin scattering) gain in a two-cell Brillouin amplification system, the invention provides the method for amplifying the two-cell Brillouin scattering by controlling the polarization state. The method is characterized in that: a light path of the pumping light is provided with a polarization state control device on the basis of the conventional Brillouin amplification technology; the polarization state of the pumping light is precisely changed by the polarization state control device; when the polarization state of SBS seed light remains unchanged, a polarization included angle between two beams of light can be controlled by changing the polarization state of the pumping light; one light power meter receives the SBS seed light (which is not amplified by amplified light) before an amplification cell, while the other light power meter receives amplified SBS signal light; and an SBS gain coefficient is obtained by comparing and calculating the readings of both the power meters.

The invention provides a dual-polarized antenna applicable to a wireless local area network and a manufacturing method of the dual-polarized antenna. The antenna comprises two dielectric plates and a grounding plate, which are the same square and overlapped and fixedly connected with one another in the same manner; the upper surface of the first dielectric plate is a metal radiation patch located at the center; two micro-strip feeder lines, which are vertical with each other and are respectively located on the two adjacent edges of a square, are arranged between the two dielectric plates; symmetrical convex rectangles are formed on the four edges of the metal radiation patch; and four cross-shaped grooves in center symmetry are arranged on the grounding plate. The manufacturing method of the antenna comprises the following steps of: respectively manufacturing single-faced and double-faced copper-coated plates to be square plates which are taken as the first and second dielectric plates; etching the first dielectric plate to obtain the metal radiation patch; etching the second dielectric plate to obtain the two micro-strip feeder lines, wherein the bottom face of the second dielectric plate is taken as the grounding plate; machining the four cross-shaped grooves in center symmetry on the bottom face of the grounding plate; connecting the dielectric plates in a laminated manner; and mounting a feeder interface. The dual-polarized antenna provided by the invention is simple in structure and small in thickness, is obviously minimized while property indexes are improved and is strong in maneuverability, and antenna parameters are convenient to adjust.

The invention discloses a transconductance amplifier with low noise and a high output resistance. The transconductance amplifier is provided with a transistor M1, a transistor M2, a transistor M3, an inductor Lm, an inductor Lg, a capacitor Cd, a capacitor Cb, a resistor R1 and a resistor R2. An input signal is connected with the grid of the M1; the source of the M1 is grounded; a bias is added to the grid of the M1 via the R1; the drain of the M1 is connected with the source of the M3, one end of the Cd and one end of the Lm; the other end of the Cd and the other end of the Lm are connected with the grid and the source of the M2, respectively; the source of the M2 is connected with one end of the Cb, while the other end of the Cb is grounded; the R2 is arranged between a Vdd and the grid of the M2; the Lg is arranged between the source of the M2 and the Vdd; the drain of the M2 is connected with the grid of the M3; and the drain of the M3 is a current output end. As feedback is introduced, the voltage between the grid and source of the M3 is enhanced, the equivalent transconductance is improved, the output resistance is increased, and the noise brought by the M3 is inhibited. The transconductance amplifier has the characteristics of high transconductance and output resistance and low noise, and is applicable to the application occasions such as a millimeter wave low noise amplifier.

A method for improving gain performance of a Viterbi decoder wherein data relating to the best path and a secondary path are stored for the Viterbi decoder. Slicer errors are determined for the best path and the secondary path for current symbols using the stored data and errors for previous symbols are corrected responsive to the determined slicer errors.

The invention discloses a automatic gain control method for digital audio frequency comprising following steps: (1) computing instant power of input signal, (2) detecting if signal of step 1 is background noise, (3) updating gain coefficient g(n) according to power information of input signal of step 1 and self-adaptive filtering study step update, (4) producing new output signal according to newgain coefficient of step 3, (5) computing instant power of output signal, (6) shaping gain (7) performing saturation control and output digital audio frequency signal. The inventive digital audio frequency automatic gain system comprises: a first power computing module, self-adaptive filter module, a second power computing module and gain shaping module. The inventive method and system can automatically control gain for digital audio frequency signal, enable output signal more balanced and smooth, and can be used in voice communication and recording system.

The invention relates to a digital-analog hybrid cylindrical phased array antenna for ad-hoc network communication, and belongs to the technical field of wireless communication and antennas. The antenna comprises an antenna array plane, n m-channel TR assemblies and an intermediate frequency acquisition processing module, a digital multi-beam forming processing module, a beam control module, a modulation and demodulation module and the like, and each channel of each TR assembly is provided with k output branches; the antenna array surface is composed of m*k*n antenna array elements which are arranged in a rectangular shape with the circumferential direction as the row and the axial direction as the column. The antenna array plane is equally divided into k areas in the circumferential direction, k branches of each channel of the TR assemblies are connected with k array elements located in different areas in a one-to-one correspondence mode, and the ith TR assembly is exactly connected with the ith array element in each area. The antenna has the advantages of large capacity, the high speed and good anti-interference and anti-interception capabilities, the performance of an ad-hoc network communication system is improved, and the application range of an ad-hoc network communication product is expanded.

The invention discloses a selenium sodium alginate and selenium chitosan coated probiotic double-layer microcapsule as well as a preparation method and application thereof. The preparation method comprises the following steps of treating sodium alginate and chitosan with sodium selenite to prepare selenium sodium alginate and selenium chitosan; embedding probiotics with the selenium sodium alginate and the selenium chitosan; and using Ca<2+> crosslinking to acquire the probiotic double-layer microcapsule. The selenium sodium alginate and selenium chitosan coated probiotic double-layer microcapsule provided by the invention can exert the effect of probiotic colonization to improve intestinal microecology and can further replenish selenium elements essential for a human body to enhance the immunity of an organism and further strengthen the gain effect of the probiotics to the human body.

The embodiment of the invention discloses an audio processing method and device, computer equipment and a storage medium. The audio processing method comprises the steps of: obtaining positive samplefrequency spectrum characteristics of positive sample audio, and obtaining negative sample frequency spectrum characteristics of negative sample audio; determining the predicted audio gain of the negative sample audio based on the sample gain prediction model and the negative sample spectrum characteristics; determining a sample audio gain of the negative sample audio according to the positive sample frequency spectrum feature and the negative sample frequency spectrum feature, adjusting a model loss function of a sample gain prediction model according to the sample audio gain or the prediction audio gain, and training the sample gain prediction model according to the adjusted model loss function to obtain a target gain prediction model, wherein the target gain prediction model is used forpredicting the target audio gain of the target audio. By adopting the audio processing method and device, the prediction accuracy of the prediction model can be improved.

A laminated vehicle window has different glass substrates and a low-emissivity (low-E) coating on an interior surface thereof, so that the low-E coating is to be located adjacent and exposed to the vehicle interior. In certain example embodiments, the low-E coating includes a transparent conductive oxide (TCO) layer of a material such as indium-tin-oxide (ITO). In certain example embodiments, the exterior glass substrate contains more iron, and is thus more absorbing of IR radiation, than the interior glass substrate.

The invention discloses a compact dual-band antenna of large frequency ratio covering sub-6G and 60GHz. The compact dual-band antenna comprises a dielectric substrate, a broadband monopole, a compact microstrip resonant unit, a millimeter wave decoupling patch array, a rectangular metal floor and a lumped port. The broadband monopole is printed on the upper surface of the dielectric substrate, consisting of a circular microstrip line and a microstrip feed line. The compact microstrip resonant unit is connected to the millimeter wave decoupling patch array and the microstrip feed line. The millimeter wave decoupling patch array comprises millimeter wave patches, rectangular slottings and decoupled microstrip lines. The rectangular slottings are located on the millimeter wave patches, and the decoupled microstrip lines are located between the millimeter wave patches. The rectangular metal floor is printed on the lower surface of the dielectric substrate. The lumped port is connected to the millimeter wave decoupling patch array and the rectangular metal floor for feeding. The compact dual-band antenna of the invention has wide frequency band and high gain effect, and can meet the application requirements of the 5G low frequency band and the 60GHz millimeter wave band.

The invention provides a radome, an antenna structure and a wireless electronic device. The antenna structure comprises a radome and a radiator located inside the radome; Where (n-1) *[Lamda]1 / 2 (H1 (n*[lamda]1 / 2, H1 denotes the thickness of the radome,[Lamda]1 denotes the propagation wavelength of the electromagnetic wave emitted by the radiator in the radome, and n is a positive integer; And / or,L=a*b*[lambda]0, L denotes the length of the line segment from the radiation surface of the radiator to the inner side of the radome, the centerline being a straight line perpendicular to the radiation surface of the radiator, [lambda]0 denotes the propagation wavelength of electromagnetic waves emitted from the radiator in air, a denotes a preset parameter, and b is a positive integer. In this way, the directivity and gain effect of the electromagnetic wave beam can be enhanced, so as to compensate the loss of the electromagnetic wave in the wireless transmission and achieve a longer wireless transmission distance, thereby improving the overall performance of the antenna structure, reducing the area, circuit complexity and corresponding cost required by the conventional design, and enhancing the overall competitiveness of the product.

The invention discloses a full positive dispersion and full polarization maintaining optical fiber laser. The full positive dispersion and full polarization maintaining optical fiber laser comprises a first optical fiber coupling Faraday polarization rotating mirror, a ytterbium-doped fiber, a wavelength division multiplexer, a pump light isolator, a semiconductor laser LD, a polarization maintaining optical fiber coupling polarization beam splitter, a polarization maintaining optical fiber coupling total reflecting mirror, a polarization maintaining optical fiber coupler, a polarization maintaining single-mode fiber, a second optical fiber coupling Faraday polarization rotating mirror and a narrow-linewidth band-pass filter. Through the design of a cavity structure, when laser pulse has a single round trip in an optical fiber laser cavity, the laser pulse is amplified multiple times, pulse gains are increased, and the single pulse energy of output light pulse is higher. Through the optical fiber coupling Faraday polarization rotating mirrors at the two ends of a standing wave cavity, the whole optical fiber laser cavity compensates the linear noise and disturbance caused by the environment and is not influenced by the outside. The full positive dispersion and full polarization maintaining optical fiber laser is simple in structure, easy to debug and small in environment interference, and has broad application prospects in the industrial field.

The invention discloses a cavity filtering antenna with high gain, high selectivity and low loss. The cavity filtering antenna comprises a dielectric plate, a first metal block, a second metal block,a third metal block and a fourth metal block, a preset distance is kept between the dielectric plate and the first metal block to form an air layer, the fourth metal block is provided with a waveguideexcitation port used for inputting energy, the second metal block is provided with a three-mode resonant cavity, the third metal block is provided with a coupling hole used for coupling the energy ofthe waveguide excitation port to the three-mode resonant cavity, and the first metal block is provided with a radiation hole used for radiating energy. The dielectric plate is provided with a grid slotted patch for improving the gain of the antenna. According to the invention, within the frequency range of 9.8 GHz to 10.2 GHz, the return loss is not larger than -11 dB, meanwhile, the gain is keptat 10 dBi, a transmission zero point is generated at the 9.76 GHz frequency point and the 10.4 GHz frequency point, the low-loss, high-gain and high-selectivity filtering performance is achieved, andmeanwhile the characteristics of being simple in design, low in machining cost and low in loss are achieved.

The invention relates to a microchannel plate and a preparation method thereof. The preparation method comprises the steps of 1) performing bar-tube combination, wiredrawing, plate layout, melting, pressing, mechanical processing and acid cleaning on a core glass bar and a skin glass tube to obtain a microchannel plate blank; 2) performing ion exchange, cleaning, high-temperature reduction and film coating on the microchannel plate blank in molten salt to obtain a microchannel plate, wherein the molten salt comprises rubidium salt and / or cesium salt. According to the invention, ion exchange isperformed on the microchannel plate blank, so that rubidium ions and cesium ions with high atomic weight and large atomic radius replace potassium ions and sodium ions in a reflecting layer, the electron flushing resistant performance of the reflecting layer is improved by the aid of increase in atomic weight of alkali metal ions and a volume congestion effect, so that the service life and the gain performance of the microchannel plate are improved, and the service life and the gain of the microchannel plate are improved by more than 30% and 20% respectively.

The invention belongs to the wireless communication technology field and especially relates to an unmanned aerial vehicle, an antenna array based on an unmanned aerial vehicle cluster, a control system and a control method. In the invention, a traditional fixed-arranged antenna array is split into several antenna units which can move freely, and the unmanned aerial vehicle is used to carry out scheduling. An antenna array size can be adjusted through a flying unmanned aerial vehicle cluster scale. A degree of freedom of array arrangement is large. The antenna array can control flight layout ofthe unmanned aerial vehicle, and reconstruct an antenna array shape and an antenna unit array arrangement mode according to a user terminal demand. Because restrictions of a large-scale antenna arraymechanical structure and a dimension envelope, and especially restrictions of motion platform weight and a volume are eliminated, a large-scale or ultra-large scale array surface can be acquired at alow frequency band. Therefore, a high gain capability is easy to acquire; the antenna array possesses a traditional amplitude and a phase weight variable and also possesses a weight capability of a space position adjusting change (such as a density weight) so that flexible and changeable directional diagrams can be realized, which includes a scanning range; and antenna array maneuverability is good.

The invention discloses an antenna mechanism. Four first rectangular antennas, each two of which are mutually orthogonal to each other, are arranged on an antenna substrate. A phase-shifted feed network is arranged on the antenna substrate and is used for feeding power to the four monopole antennas, wherein the feeding phases are orthogonal to each other. According to the invention, with the fourfirst rectangular antennas arranged orthogonally, the circular polarization of the antenna is realized based on a feeding mode with the orthogonal feeding phases; and on the basis of the setting modeof all parts of the antenna mechanism, technical effects of miniaturization and high gain of the antenna mechanism are guaranteed.

The invention discloses a purpose of a water-quality purifying agent containing biological enzymes, and particularly relates to the purpose of the water-quality purifying agent containing biological enzymes for polluted water quality purification. The water-quality purifying agent is prepared from the following ingredients in parts by weight: 20 to 25 parts of enzyme loading sorghum straw active carbon, 4 to 6 parts of sodium alginate, 6 to 8 parts of polyferric chloride, 3 to 7 parts of polyaluminium chloride, 30 to 35 parts of modified bentonite, 3 to 7 parts of polyacrylamide, 3 to 8 partsof plant fiber and 200 to 300 parts of distilled water. The purpose has the beneficial effects that all of the ingredients in the water-quality purifying agent can achieve the cooperated effect; through physical and chemical adsorption, harmful substances such as nitrogen, phosphorus, organic matters and heavy metal ions in the sewage can be effectively eliminated, so that impurities, eutrophication substances and the like can be settled through flocculation; meanwhile, the relatively good surface performance is realized; the selective adsorption effect on the organic contaminants is good.

The invention relates to a low-wear scratch-resistant ABS material and a preparation method thereof. Blending of ABS with PMMA and addition of an inorganic filler, a slip agent and the like improve the resistance of the ABS to wear and scratch in order to solve the problem of poor wear resistance of the ABS. The low-wear scratch-resistant ABS material comprises, by weight, 70-90 parts of ABS resin, 10-30 parts of polymethyl methacrylate, 1-5 parts of maleic anhydride grafted styrene, 0.2-2 parts of a lubricant, 0.2-2 parts of an antioxidant, 0.5-10 parts of the slip agent, 0.5-5 parts of silicone master batches and 2-20 parts of the inorganic filler. The prepared ABS has a high pencil hardness, and has a lower wear resistance than the ordinary ABS, and the mechanical properties and the processing fluidity are not significantly less than those of the ordinary ABS.

The invention relates to a slab laser amplifier and a laser output method. The slab laser amplifier comprises a gain dielectric module, pumping modules, and a reflector module, wherein the reflector module comprises two reflectors which are located on the left and right sides of the gain dielectric module; the pumping modules are located on the front and rear sides of the gain medium module; laser crystals are 0.5-1.5mm thick and include one doped laser crystal and two non-doped laser crystals; the two non-doped laser crystals are bonded to the two long and high surfaces of the doped laser crystal without adhesive, respectively, and arranged in parallel with the doped laser crystal; after seed laser is incident into the laser crystals at a certain angle, the seed laser is reflected back and forth between the reflectors, and meanwhile, passes through the laser crystals between the reflectors, and finally, the power amplified laser can be output. The bonded laser crystals of an ultrathin slab structure are taken as the gain dielectric of the slab laser amplifier, the thermal effect of the laser crystals is reduced and the gain effect of the gain dielectric is improved; high-output power and high-beam quality continuous or pulse laser amplified output can be obtained.

The invention belongs to the technical field of photoelectric detection, and particularly relates to a double-waveband high-gain photoelectric detector with a graphene sandwich structure. The photoelectric detector with the graphene sandwich structure provided by the invention sequentially comprises a light absorption layer I (1), a graphene layer (2) and a light absorption layer II (3) from bottom to top, wherein the graphene layer (2) is arranged between the light absorption layer I (1) and the light absorption layer II (3) to form the sandwich structure; and a metal electrode (4) is arranged on the surface of the graphene layer (2). By virtue of the sandwich structure with unique graphene in combination with the double-layer light absorption material layers, the photoelectric detector can simultaneously respond to light of different wavebands, and a high response effect is obtained; and in addition, the preparation process of the photoelectric detector is simple, and strong in practicability.

The invention discloses a mid-far infrared avalanche photodetector which comprises a substrate, a buffer layer, a lower ohmic contact layer, a multiplication layer, a charge layer, a gradient layer, an absorption layer and an upper ohmic contact layer which are sequentially connected from bottom to top, and the doping type of the substrate and the buffer layer is n type. Or the mid-far infrared avalanche photodetector comprises the substrate, the buffer layer, a second ohmic contact layer, the absorption layer, the gradient layer, the charge layer, the multiplication layer and a first ohmic contact layer which are sequentially connected from bottom to top, and the doping type of the substrate and the buffer layer is p type, wherein the multiplication layer is made of an AlAsxSb1-x material, x is greater than or equal to 0.12 and less than or equal to 0.18, the gradient layer is of a plurality of (InAs)m / (AlAs0.15Sb0.85)n quantum well structures or an InyAl1-yAszSb1-z material, and thedetection wavelength of the absorption layer is a middle and far infrared band. The mid-far infrared avalanche photodetector provided by the invention can block dark current and reduce noise, does notneed a cooling device, improves the working temperature of the device, reduces the cost, and is convenient to use.

The invention provides a satellite signal acquisition method and device. The method includes the following steps that: down sampling processing is performed on the signal pseudo codes of transmission signals of N cycles, so that second type signal pseudo codes can be obtained; the second type signal pseudo codes and local pseudo codes in each cycle are evenly divided into P segments of signal pseudo codes respectively; coherent accumulation is performed on the second type signal pseudo codes in each segment of signal pseudo codes in each cycle under corresponding segments respectively; the number of the times of initial bit jump in a previous cycle in adjacent cycles is obtained; the number of the times of final bit jump in each cycle is obtained; the second accumulated value of the P segments is obtained according to the number of the times of final bit jump in each cycle; and fast Fourier transformation is performed on the second accumulated value of the P segments, and satellite signals are acquired according to a local acquisition threshold value. The satellite signal acquisition method and device provided by the embodiments of the invention is suitable for the acquisition of satellite signals of a plurality of cycles, and time for coherent integration can be increased, and satellite signals with lower intensity can be acquired, and the sensitivity of signal acquisition can be improved.