39 results about "Mismatch loss" patented technology

A novel and useful apparatus for and method of improving antenna matching and reducing mismatch loss for a VHF receiver such as an FM receiver. The invention can be used in a very low cost implementation of a single chip radio such as used in cellphone applications. The impedance of the low cost VHF antenna in cellphone application can dramatically vary across time, frequency and depending on the human body proximity resulting in a large mismatch loss. The adaptive antenna matching mechanism uses dynamically configurable on-chip variable capacitors to provide a custom matching network with the external inductor in a pi-network configuration. The variable ranges of the on-chip capacitors enable adaptation in a closed loop manner so that the optimum SNR is achieved thus ensuring minimum mismatch loss. The mechanism measures RSSI and SNR and, using a novel adaptive calibration mechanism, adjusts the internal matching network capacitors such that the mismatch loss is minimized.

The invention discloses a structure for improving the coupling efficiency between a submicron silicon waveguide and a common single-mode fiber. In the structure, the substrate material for making a submicron silicon waveguide is a silicon wafer on an insulating substrate, and the silicon wafer includes three layers of materials from bottom to top: substrate silicon, a buried oxide layer and top silicon, wherein the buried oxide layer is doped silicon dioxide; after forming a submicron silicon waveguide on the top silicon of the wafer through photoetching and etching, the doped silicon dioxide in the first layer is deposited on the silicon waveguide and fully covers the silicon waveguide; and after the doped silicon dioxide in the layer is photoetched and etched, the doped silicon dioxide in the second layer is deposited on the silicon waveguide. Therefore, the formed silicon dioxide waveguide is used as a connection channel for a common single-mode fiber, so that the mode field mismatch loss and the reflection loss during the coupling process of the submicron silicon waveguide and the common single-mode fiber, and the coupling efficiency between the submicron silicon waveguide and the common single-mode fiber can be improved.

The invention provides an antenna structure and a communication terminal. The antenna structure comprises an antenna radiator, a signal source, a first capacitor and a first tuning circuit; the firstend of the antenna radiator is grounded; the first end of the first capacitor and the first end of the first tuning circuit are both electrically connected with the connection point of the antenna radiator, the second end of the first capacitor is electrically connected with the signal source, and the second end of the first tuning circuit is grounded, wherein the antenna impedance of the first end of the first capacitor at a target frequency point is located in the first quadrant of the Smith chart, and the target frequency point is at least part of the frequency points in a frequency band covered by the antenna radiator. According to the scheme of the invention, on the one hand, the antenna structure can generate a new resonance mode, and the resonance mode excited by the antenna structure can be optimized; and on the other hand, the problem of impedance mismatch loss of the antenna can be improved, the impedance mismatch loss can be reduced, and the transmission efficiency of the antenna can be further improved.

The invention discloses a photovoltaic system series-parallel mismatch loss ratio test device and a test method thereof. The test device comprises a first IV curve test plate used for testing a whole string or string conflux, a plurality of second IV curve test plates used for testing a corresponding channel of each path of assemblies, series connection switching switches used for serial assemblies, parallel connection switching switches for parallel connection assemblies, test switching switches used for testing IV curves, an interface conversion plate, a PC, and a control panel. The test method additionally comprises testing once a whole IV curve based on a current test method, provides a reliable loss ratio result when the maximum power deviation of twice tests is less than a certain threshold, and substitutes a formula with the power average value of twice whole strings or stings after conflux for calculation, thereby obtaining more scientific and more reasonable measuring results.

The invention discloses a silicon-based multimode helical waveguide delay line supporting low-loss fundamental mode transmission. A curvature gradual change type S bending multimode waveguide is placed at the centers of curvature gradual change type helical bending multimode waveguides; and two curvature gradual change type helical bending multimode waveguides are annularly and helically arranged,an inner end of one curvature gradual change type helical bending multimode waveguide is connected with one end of the curvature gradual change type S bending multimode waveguide through a bending waveguide, the other end of the curvature gradual change type S bending multimode waveguide is connected with the inner end of the other curvature gradual change type helical bending multimode waveguidethrough another bending waveguide, and the entire silicon-based multimode helical waveguide delay line is arranged in a central symmetry manner. The silicon-based multimode helical waveguide delay line disclosed by the invention can effectively avoid mode mismatch loss and inter-mode crosstalk caused by the abrupt curvature change of the traditional structure, and can reduce the scattering loss introduced by a waveguide sidewall, thereby obtaining low-loss fundamental mode transmission in the silicon-based multimode helical waveguide, and the silicon-based multimode helical waveguide delay line has the advantages of low loss and compact structure and the like, and can be applied to optical buffers, optical delay lines and other systems.

The invention provides a GPS (Global Positioning System) and 3G (3rd-Generation) single-antenna realizing device which comprises a dual-resonant antenna used for receiving a radio frequency signal, a matching circuit which is connected with the dual-resonant antenna for obtaining the radio frequency signal and is used for performing signal matching processing on the radio frequency signal, and a diplexer, wherein the diplexer is connected with the matching circuit and is used for obtaining the radio frequency signal subjected to signal matching processing and sending the radio frequency signal subjected to separation processing respectively to a GPS module and a 3G diversity receiving module. The invention also provides a mobile terminal. Through the mode, according to the technical scheme disclosed by the invention, a GPS and 3G shared single antenna is realized by arranging the dual-resonant antenna, the matching circuit and the diplexer, so as to receive the signal; reflection loss and mismatch loss in the transmission process of the radio frequency signal are reduced; the transmission efficiency of the radio frequency signal is increased; the communication quality of the mobile terminal is enhanced; and the space of placing the antenna is not increased.

The invention discloses an estimation method for parallel mismatch of subarrays of a photovoltaic power station. The estimation method comprises the following steps of: carrying out IV scanning on thesubarrays to obtain IV curves; obtaining theoretical maximum output power P1 of the subarrays according to the IV curve of each string, calculating theoretical maximum output power P2 of string typeinverter subarrays; calculating theoretical maximum output power P3 of centralized type inverter subarrays; obtaining parallel mismatch loss of the string type inverter subarrays deltas and the centralized type inverter subarrays deltac. The estimation method disclosed by the invention has the advantages that IV curves of all strings of the subarrays can be measured and calculated simultaneously,the voltage differences of maximum power points of each string are obtained by testing under same conditions at the moment, so that the mismatch of working voltages among all the strings in the subarrays can be accurately evaluated.

Methods and systems for tracking signals with diverse polarization properties address both sensitivity and antenna tracking performance issues. In one embodiment, complex weightings for matching a polarization of an incident signal on a data channel are determined, and the complex weightings are applied to a tracking channel such that an antenna system polarization is matched to the polarization of the incident signal. In another embodiment, orthogonally polarized tracking channel components of an incident signal are processed to make a determination as to which of the orthogonally polarized tracking channel components is stronger, and this determination is used to select a polarization of a data channel to reduce a polarization mismatch loss.

The invention relates to a photovoltaic array serial-parallel mismatch loss analysis method. The method is characterized by comprising the following steps: carrying out superimposed calculation on the maximum power of strings through an I-V characteristic curve for modules, and carrying out superimposed calculation on the maximum power of an array through an I-V characteristic curve for the strings. According to the method, the I-V characteristics of each string are superimposed, the power of a combiner box is given through theoretical calculation but not actual measurement, an analysis result can be linked with string measurement error, the problem that the parallel mismatch analysis result is too large in deviation caused by two-stage measurement error of the strings and the combiner box in an existing analysis method is avoided, and the accuracy of analysis is guaranteed.

The invention provides a defect diagnosis method and device for a photovoltaic power station. The method includes the following steps: collecting test data during the operation of a photovoltaic powerstation to be diagnosed; according to the test data, determining an annual performance PR value of the photovoltaic power station to be diagnosed, a PR value of each power generation unit of the photovoltaic power station to be diagnosed, and the PR value, weighting efficiency, parallel mismatch loss or series mismatch loss of components included in each power generation unit; and diagnosing positioning defects of the photovoltaic power station to be diagnosed layer by layer based on a PR evaluation threshold model and according to the PR value of the photovoltaic power station to be diagnosed, the PR value of each power generation unit of the photovoltaic power station to be diagnosed, and the PR value, weighting efficiency, parallel mismatch loss or series mismatch loss of the components included in each power generation unit, wherein the PR evaluation threshold model is predetermined based on actual measured data of the photovoltaic power station on the scene. According to the above technical scheme, the defect detection of the photovoltaic power station from the operation level can be implemented, and the efficiency of defect diagnosis of the photovoltaic power station can beimproved.

The invention provides a photovoltaic string azimuth angle determination method, a string recombination method and related devices. The method for determining an azimuth angle of a photovoltaic stringis characterized in that the azimuth angle of each string can be quantified by utilizing monitoring data of a power station, namely historical electrical characteristic data and irradiation data of each string, other data do not need to be measured independently, and only required data need to be extracted from a monitoring system, so the workload of data measurement is reduced, and cost is further reduced. After an azimuth angle deviation value of the string is obtained, a string recombination method can be further utilized to judge whether the string needs to be recombined or not so as to reduce series-parallel mismatch loss of the string and provide the power generation capacity of the whole power station.

The present invention provides a series-parallel mismatch loss on-line test method. The method includes the following steps that: step 1, an on-line test device for series-parallel photovoltaic assembly mismatch testing is established; step 2, the effective data of the photovoltaic mismatch testing are acquired; step 3, the effective data of the photovoltaic mismatch testing are verified, if the effective data of the photovoltaic mismatch testing pass the verification, the series-parallel mismatch loss rate of a photovoltaic assembly is calculated; step 4, if the effective data of the photovoltaic mismatch testing does not pass the verification, the method returns to step 2, the effective data of the photovoltaic mismatch testing are acquired again; and step 5, the calculation result of the series-parallel mismatch loss rate of the photovoltaic assembly is obtained, after a test period is terminated, the on-line test device is dismantled, and the normal power generation of a photovoltaic array is restored. With the series-parallel mismatch loss on-line test method of the invention adopted, complete synchronization of the electrical performance parameters of a tested photovoltaic assembly and photovoltaic meteorological data is completed, transformation error of the transformation of measured data to an STC condition for series-parallel loss calculation in traditional series-parallel mismatch loss offline testing can be avoided, and the efficient and reliable operation of a photovoltaic power plant can be ensured.

The invention relates to a dense-condensation photovoltaic cell array reducing mismatch loss, belongs to the technical field of solar energy utilization, and aims at reducing the mismatch loss of thedense cell array under non-uniform radiation and improving the power output of the dense cell array. The dense-condensation photovoltaic cell array of a rotational symmetry structure is divided into sub-modules in rotational symmetry, cells in each sub-module are connected in parallel, serial or full manner or a parallel, serial and full mixed manner, and the sub-modules are connected in series. Connection design with rotational symmetry characteristics enables that power loss caused by current and voltage mismatch of the dense cell array module of a large condenser can be reduced obviously under the real illumination condition with Gaussian or truncated cone-shaped distribution characteristics, power output of the cell array is further improved, and the efficiency, economical performanceand reliability of a dense-condensation photovoltaic cell array power generation system are improved.

The invention discloses a method for calculating the group string -parallel mismatch loss of photovoltaic power stations, the main technical problem to be solved is the lack of calculation of group string parallel mismatch loss in the prior art, The invention adopts a method for calculating the group string parallel mismatch loss of a group of photovoltaic power stations to detect the health valueof the group string and the health value of the component. Step 2: Select sampling points on different groups of strings connected with the inverter, and measure the current value and voltage value at different times of different groups of strings through each sampling point, thus solving the problem, and can be used for calculating the group string parallel mismatch loss of the photovoltaic power station.

The embodiment of the invention discloses a photovoltaic power station configuration method and device. The photovoltaic power station configuration method comprises the following steps: acquiring configuration parameters of a photovoltaic power station and meteorological data of a project location of the photovoltaic power station; calculating the voltage of each branch from a photovoltaic stringto an inverter end based on the configuration parameters and the meteorological data; and determining photovoltaic strings accessed to the same MPPT of the inverter according to the voltage of each branch. Based on the configuration parameters and the meteorological data, the voltage of each branch is calculated, and the voltage actually output by different branches due to shadow shielding and temperature difference can be determined; the output voltages of different branches are compared, and the branches with the highest output voltage similarity are connected to the same MPPT, so that theproblem that the photovoltaic power station generates large parallel mismatch loss due to the fact that branches with large output voltage difference are connected in parallel without considering shadow shielding and temperature difference at present is solved, the parallel mismatch loss of the photovoltaic power station is reduced, and the power generation efficiency of the photovoltaic power station is improved.

The invention discloses a method for calculating mismatch loss of the back surface of a double-sided photovoltaic module, which comprises the following steps: equally dividing the back surface of thedouble-sided photovoltaic module into n parts to form n parts, wherein n is an integer greater than or equal to 2; respectively calculating irradiation of n parts on the back surface of the double-sided assembly; converting the maximum irradiation of the back surface into an electrical model to calculate the power of the back surface of the double-sided assembly; and respectively converting the irradiation of the n parts of the back surface into an electrical model for power calculation, comparing the maximum power with the mismatch power at the moment, and calculating and obtaining the mismatch loss of the back surface of the double-sided assembly. According to the invention, irradiation of each part of the back surface of the double-sided photovoltaic module can be obtained; and design optimization can be carried out according to the characteristics of the back surface of the double-sided assembly, for example, for the fixedly-installed double-sided assembly, the mismatch loss causedby the non-uniform irradiation of the back surface of the double-sided assembly at different installation heights is calculated and compared, the design of a double-sided system is optimized, and thepower generation capacity of the system is improved.

The invention discloses a mismatch loss calculation method and device, equipment and a storage medium. The back surface of the double-sided assembly is divided to obtain at least one area; the back face of the double-face assembly is the face, back to a light source, of the double-face assembly. For each area, the ideal irradiance of the area in the state that the back face is not provided with the support and the actual irradiance of the area in the state that the back face is provided with the support are determined; and the mismatch loss of the back surface is determined according to the ideal irradiance of each region and the actual irradiance of each region. According to the technical scheme, a new thought is provided for calculation of the mismatch loss of the back face of the double-face assembly, and meanwhile support is provided for design of a related system for subsequently improving the generating capacity by evaluating the shielding influence of the supporting object on the double-face assembly.

The invention provides a component evaluation method and system for a photovoltaic power station. The method comprises the steps of determining a voltage value and a current value of each bypass diodein a to-be-evaluated photovoltaic string of the photovoltaic power station; calculating first power of the to-be-evaluated photovoltaic string when no current flows through each bypass diode in the to-be-evaluated photovoltaic string; moreover, when current flows through at least one bypass diode in the to-be-evaluated photovoltaic string, calculating the second power of the to-be-evaluated photovoltaic string according to the voltage value and the current value of each bypass diode in the to-be-evaluated photovoltaic string, and finally, using the difference value obtained by subtracting thesecond power from the first power as the mismatch loss of the to-be-evaluated photovoltaic string. Therefore, the to-be-evaluated photovoltaic string is used as a node, the series mismatch loss inside the photovoltaic modules and between the photovoltaic modules in the to-be-evaluated photovoltaic string can be calculated, the mismatch loss calculation is accurate to the module level, and the evaluation precision of the photovoltaic power station is improved.