104 results about "Amplitude weighting" patented technology

A technique is disclosed for calculating the phase and amplitude weighting factors for use with a specific compact antenna range that synthesize an in phase, constant amplitude planar wave front that appears to have been transmitted from the far field. The weighting factors are used to weight RF signals after they are received by a full size or scaled radio direction finding array mounted on a platform during testing of the antenna array on the compact antenna range. The weighted received signals accurately replicate the antenna array response in the far field, including electromagnetic glint caused by the platform on which the antennas are mounted, and are stored in complex voltage form as a calibration table for the array.

Method and apparatus for a frequency diverse array. Radio frequency signals are generated and applied to a power divider network. A progressive frequency shift is applied to all radio frequency signals across all spatial channels. Amplitude weighting signals are applied for sidelobe control. Phase control is included for channel compensation and to provide nominal beam steering. The progressive frequency offsets generate a new term which cause the antenna beam to focus in different directions as a function of range. Alternative embodiments generate different waveforms to be applied to each radiating element, permitting the transmission of multiple signals at the same time.

Method and apparatus for a frequency diverse array. Radio frequency signals are generated by a plurality of independent waveform generators and simultaneously applied to a transmit / receive module. A progressive frequency shift is applied to all radio frequency signals across all spatial channels. Amplitude weighting signals are applied for sidelobe control. Phase control is included for channel compensation and to provide nominal beam steering. The progressive frequency offsets generate a new term which cause the antenna beam to focus in different directions as a function of range.

A beam-forming network having: a plurality (NI) of input signal ports (IP); a plurality (NO) of output signal ports (OP); a weighting and interconnecting network (WIN) comprising a plurality of signal dividers (SD), phase and amplitude weighting elements (WE), switches (SW1, SW2) and signal combiners (SC), for associating each input port to output ports through respective weighting units; wherein either input (IP) or output (OP) ports, or both, are partitioned into disjoint equivalence classes (IEC, OEC), at least a majority of said equivalence classes having more than one port; and in that the network is either configured in order to associate each input port to at most one output port for each output equivalence class, or to associate each output port to at most one input port for each input equivalence class, or both. Also provide is a multibeam antenna comprising having such a beam-forming network, and an electronic circuit for implementing such a beam-forming network.

The invention relates to a wave beam construction network with continuous variable differential phase, which comprises: a metallic chamber which contains power divider and several phase shifters. Wherein, said power divider comprises a main power divider and several sub power divider. Each phase shifter is distributed at two sides inside the metallic chamber according to the different direction of phase shift; a insulator is arranged between them connecting each phase shifter; the insulator is connected to a medium rod; the metallic chamber has a operation hole for operating said medium rod. The invention can be constructed integrated, while it can realize phase shift and the power amplitude weighting, with simple structure, small volume, simple producing process and lower cost. In addition, the metals of movable and fixed parts of phase shifter use untouched capacitor coupling signal transmission to restrain the passive product and the high power fire strike.

The invention discloses a centralized MIMO radar wave shape online designing method mainly aiming to solve the problems that a transmitting direction diagram can not be designed on line and the wave shape of a transmitted signal can not be synthesized on line by utilizing the traditional methods. The method comprises the following steps of: (1) carrying out amplitude weighting on an MIMO radar array, and constructing a fundamental wave beam bank with lower airspace sidelobe off line; (2) based on sequence quadratic programming, constructing various proportions of orthotropic fundamental wave shape banks which have low autocorrelation peak sidelobe level and low peak cross-correlation level off line; (3) solving the transmitting proportion of fundamental wave beams synthetizing the given transmitting direction diagram on line by utilizing linear programming; (4) selecting the fundamental wave shapes meeting the demand from the orthotropic fundamental wave shape banks according to the transmitting proportion of the fundamental wave beams; and (5) respectively synthetizing the transmitting direction diagram and a transmitting signal wave shape by the selected fundamental wave beams and the fundamental wave shapes. Compared with the traditional wave shape designing method, the invention can realize the online wave shape design and can be used for the self-adaption tracking of an MIMO radar on a moving target.

The invention discloses an amplitude weighting-based ground penetrating radar back projection imaging method, which belongs to the field of radar imaging. The traditional back projection imaging method has the problem of insufficient clutter and noise suppression ability. According to the amplitude weighting-based ground penetrating radar back projection imaging method, as for any imaging point A, time delay is used for calculating a scattering response amplitude xA,k=rk(t), and t=tauA,k of the imaging point in each channel; a response amplitude corresponding to a point on hyperbolic echo is acquired through edge extraction to form a window function; weighting is carried out on the scattering response amplitude xA,k of each channel, and imaging on the A point is completed through coherent superposition; and all imaging points are traversed to complete the entire imaging process. The window function is used for carrying out weighting processing on the scattering amplitude, the target detection precision is improved, and the noise and clutter interference suppression ability is improved.

The invention provides a signal phase difference estimation device in an antenna aligning array based on circulating cross-correlation, and the antenna aligning array comprises a plurality of receiving antenna units. The device is used for calculating the phase differences of antenna signals of the antenna aligning array in stable circulation, and comprises one or two matched filters, a circulating cross-correlation module and a phase difference resolving module, wherein the filter is used for matched filtering for the antenna signal which is subjected to time delay, amplitude weighting and phase adjustment, and matched filtering for a difference signal between the signal which is subjected to time delay, amplitude weighting and phase adjustment and a reference signal; the circulating cross-correlation module is used for calculating a circulating cross-correlation function of the signal and the difference signal which are both subjected to matched filtering; and the phase difference resolving module is used for calculating the phase difference of the antenna signal according to the circulating cross-correlation function. The invention also provides a signal phase difference estimating method in the antenna aligning array based on circulating cross-correlation, a signal synthesis device, a signal synthesizing method, an antenna aligning array signal receiving system and an antenna aligning array signal receiving method.

The invention discloses a phase position continuous linear-variable phase shifter for a base station electrically controlled antenna, which comprises a power divider group, transmission lines and medium baseplates, wherein the power divider group comprises a main power divider and a plurality of slave power dividers; the power dividers and the transmission lines are realized in a strip line structure; the medium baseplates are positioned between a transmission line circuit and an upper layer floor, and between the transmission line circuit and a lower layer floor; and the power divider group, the transmission lines and the medium baseplates are integrally designed. According to the invention, the phase shift is realized, and at the same time, the power amplitude weighting of each output port is also realized. The phase shifter has the advantages of simple structure, easiness in processing, and low cost. A phase shift element adopts a medium baseplate structure, and the passive intermodulation product is suppressed. The power divider group and the transmission line circuit adopt a strip line structure, and the power capacity of the phase shifter is increased.

The invention provides a detection method and equipment for an underwater target. The detection method includes the steps: receiving received signal of each array element in a towed line array, conducting fast Fourier transform analysis to received signal of each array element, and acquiring spatial spectrum of each frequency unit, taking a maximum amplitude value of spatial spectrum of the each frequency unit; by means of the maximum amplitude value, conducting amplitude value weighting to spatial spectrum of the each frequency unit; and finally conducting accumulation for a sum to the spatial spectrum of the each frequency unit post-weighting. When the target radiating line spectrum signal is weak, compared with the untreated by amplitude value weighting, the detection property of the amplitude-weighting-based target detection method can be effectively improved.

The invention relates to an earthquake prestack migration imaging method which includes the following steps: (1) obtaining observing system information and data features by scanning earthquake records, and calculating to obtain migration initial parameters; (2) launching gauss beam central ray from a cannon point, and calculating travel time and amplitude weighting factors in a nearby area of the ray; (3) launching ray from all gauss beam central positions of a demodulator probe wave field, and calculating travel time and amplitude weighting factors in a nearby area of the ray; (4) by using the travel time and the amplitude weighting factors of the gauss beam at the cannon point and the gauss beam at the demodulator probe position to a certain underground point, the earthquake record is returned to the position according to travel time information and amplitude weighting factor information; (5) repeating the step (1) to the step (4) for each cannon earthquake record, migration results of all canons are obtained and stacked according to corresponding positions to obtain a migration stacking result of a cannon set, and a final migration result is obtained by filtering false appearances on a wave field path. The earthquake prestack migration imaging method can obtain migration imaging in a key target area fast and can be widely applied to various oil gas exploration processes.

The invention belongs to the technical field of antennas and particularly relates to a series feed microstrip array antenna which is applicable in a millimeter wave radar system and wireless communication field. The array antenna comprises a medium plate, a paster array antenna and a metal land. An array paster unit is formed by two groups of paster units which are axisymmetrically arranged along axes of feed through holes. Each group of the paster units comprises six microstrip pasters which are successively separately arranged along the length direction of the medium plate and are distributed according to the Chebyshev 25dB amplitude weighting. The interval between adjacent two microstrip pasters in the same paster unit is equal to a half of a wavelength. Every adjacent two microstrip pasters are connected with each other through impedance matching segments in the shape of triangular gradually changed lines. One coaxial feed probe is connected with relatively close microstrip paster on the same group of the paster units through a 180-degree phase shifter. The array antenna is advantaged by high gain, low minor lobe and miniaturization, and requirements of high integration and miniaturization of the whole antenna structure can be effectively achieved.

The invention provides a rectangular forming antenna array. Rectangular forming beams, capable of rapid falling, of a directional diagram can be realized through array layout, amplitude weighting, and phase configuration by employing a few of array units of forming antennas. The rectangular forming antenna array comprises four array units of a first loop, eight array units of a second loop, and four array units of a third loop, and the array units of the three loops are concentric. Therefore, by employing the rectangular forming antenna array, coverage overlapping or dead zones of adjacent multiplexing cells can be effectively eliminated, a better effect of rectangular beam forming is realized, the minor lobe is reduced, the quantity of array units is reduced, miniaturized and low-weight design of the rectangular forming antennas is realized, the rectangular forming antenna array can be better applied to the field of mobile communication etc., and goals of reducing the cost and saving the time can be achieved.

The invention discloses a method for calculating an anisotropy azimuth angle by using dipole transverse wave logging information based on a frequency domain. The method comprises the following steps of selecting a waveform of a transverse wave part in a dipole transverse wave logging waveform by using a time window; carrying out FFT (Fast Fourier Transform) for the selected waveform, and obtaining an anisotropy azimuth angle curve which changes with the frequency; obtaining an anisotropy azimuth angle curve after the amplitude weighting by multiplying the anisotropy azimuth angle curve by a magnitude spectrum of a waveform XX or YY; stacking the anisotropy azimuth angle curves calculated by different spacing waveforms, and obtaining a total anisotropy azimuth angle curve; fixing the interval of an azimuth angle, changing the azimuth angle, and calculating the count of azimuth angle curves in the interval of the azimuth angle; and taking a maximum value of an azimuth angle distribution curve as a value of the anisotropy azimuth angle obtained in the depth. According to the method for calculating the anisotropy azimuth angle by using the dipole transverse wave logging information based on the frequency domain, disclosed by the invention, compared with the azimuth angle calculated by a time domain, the azimuth angle is relatively concentrated, and the influence due to the waveform amplitude difference excited by dipoles in an X direction and a Y direction is small.

An antenna system for sharing of operation employs contiguous transmit frequencies. Transmit frequencies are separated into non-contiguous sub-groups isolated from one another by filters 158(+) and 160(−) associated with positive and negative polarization. Received frequencies are filtered and split into five signals for input to base station receive ports. Non-contiguous transmit frequency sub-groups are combined by a quadrature hybrid 110 and pass with 90 degree relative phase shift to mutually orthogonal antenna stack ports P(+) and P(−) associated with orthogonally polarized sets of antenna elements AS(+) and AS(−): the ports P(+) and P(−) are isolated from one another by the hybrid 110. The 90 degree phase shift results in one transmit subgroup being radiated with left hand circular polarization and the other transmit subgroup being radiated with right hand circular polarization. Changing the relative phase shift changes the radiated polarization to linear or elliptical, and signal amplitude weighting provides control of antenna beam polarization direction.

The invention relates to a time reversal orthogonal FDM (Frequency-Division Multiplexing) wireless communication method based on SFME (Solvent Free Microwave Extraction). The method comprises the following steps of generating serial random binary bit stream by a data source; performing serial-parallel conversion so as to ensure that the parallel bit data velocity is changed to be 1 / N of serial velocity; performing QPSK (Quadrature Phase Shift Keying) modulation treatment so as to ensure that the parallel bit sequence is changed into a parallel complex number sequence dn=an+jbn; before performing quadrature modulation, performing amplitude weighting on dn by use of a subcarrier frequency domain amplitude equalizer; performing IFFT, cyclic prefix adding and serial-parallel conversion treatment on a parallel signal obtained by the subcarrier frequency domain amplitude equalizer, then transmitting the signal to a wireless channel by virtue of a time reversor; and performing corresponding OFDM (Orthogonal Frequency Division Multiplexing) demodulation on the received signal at a receiving terminal. According to the method, the side lobe of the focused time domain of each subcarrier time reversal signal is eliminated, so that coherent multipath interference of an OFDM system in an abundant scattering environment is eliminated, the code error rate of the system is reduced, and the defect that a multipath equalizer needs to be adopted in a traditional communication system to perform channel equalization is overcome.

The invention discloses a method and device for transmitting coding indicator information, and a method and device determining a precoding matrix and is used for solving the problem that resolution of codons in a codebook which is generated by combining beam vector subgroups and column selection cannot be adjusted flexibly. The method for transmitting the coding indicator information comprises the steps that user equipment determines first precoding indicator information and second precoding indicator information, wherein the first precoding indicator information corresponds to a first level precoding matrix, the first level precoding matrix comprises beam vectors in different polarization directions, the second precoding indicator information corresponds to a second level precoding matrix, the second level precoding matrix is used for carrying out amplitude weighting and phase adjustment on all beam vectors in each polarization direction of the first level precoding matrix, and the first level precoding matrix and the second level precoding matrix are used for generating the precoding matrix. The resolution of the precoding matrix is adjusted flexibly by carrying out the amplitude weighting and phase adjustment on all beam vectors in each polarization direction of the first level precoding matrix, and the system performance is improved.

The invention discloses a system allowing for phased-array amplitude weighting. The system is applied between an external circuit and a target system and comprises a wave beam generation module and a phased-array antenna module. The wave beam generation module is coupled with the external antenna and the phased-array antenna module. The phased-array antenna module is coupled to the wave beam generation module and the target system. The problems of lowering side lobe level in a phased array, lowering cost and facilitating implementation are solved by the use of the system.

The present invention discloses a multi-input multi-output communication system based on relay and a communication method thereof, and belongs to the field of wireless communication. The structure of the invention comprises a transmitter, a forwarding device and a receiver. The forwarding device is composed of relays. Each relay equally comprises a phase rotator and an amplitude amplifier. The communication method comprises the following steps: executing preprocessing to the signal to be transmitted by the transmitter for obtaining the column vector signal before transmission; amplifying the received signal by the amplitude amplifier of each relay in the forwarding device, adjusting the phase of received signal by the phase rotator; and executing amplitude weighting and phase rotating to the duplicate copies of a plurality of received channel by two maximal ratio combiners in the receiver. The system and method of the invention have higher spectrum efficiency and better probability capability. Each replay independently processes and forwards the received signal. The complexity and feedback expenditure of cooperative processing are reduced.

Amplitude phase distortion adding sections are provided for the power amplifiers on the antenna arrays greater in amplitude weighting while amplitude distortion adding sections are provided for the power amplifiers on the antenna arrays smaller in amplitude weighting. Due to this, because a required amount of distortion compensation is made based on each antenna array, there is no bad effect upon the adjacent other antenna array, suppressing the deterioration in beam control accuracy. This, also, reduces the size of the apparatus and improves the power efficiency on the array antenna apparatus overall.

The invention relates to the field of broadband array antennas, in particular to a broadband active multi-beam antenna system, which comprises a broadband active antenna array and a multi-beam network, wherein the broadband active antenna array comprises at least two column line sources and multifunctional radio-frequency front ends and a control unit; the column line sources receive multiple paths of radio-frequency signals and carry out pitching direction synthesis; the multifunctional radio-frequency front ends carry out low-noise amplifying, filtering, amplitude weighting and phase shift processing on the radio-frequency signals output by the column line sources; the control unit receives a control instruction input from the outside and adjusts attenuation and phase shift code values in the multifunctional radio-frequency front ends; and the multi-beam network synthesizes the radio-frequency signals output by the multifunctional radio-frequency front ends on the basis of lens network implementation and simultaneously outputs multiple paths of beams in an azimuth direction. A near field diameter inversion correction method is adopted by the broadband active multi-beam antenna system. Compared with a broadband multi-beam system formed by digital beams, the broadband active multi-beam antenna system has the advantages that the equipment quantity is greatly reduced, the weight, the cost and the power consumption are greatly reduced and the broadband active multi-beam antenna system is easily applied to engineering.

The invention discloses a flat panel array antenna used for the frequency range of 10 GHz-100 GHz. The flat panel array antenna is characterized by comprising a flat panel reflector, a waveguide power divider and an antenna radiating unit, wherein the waveguide power divider is connected with the output end of the flat panel reflector, and the antenna radiating unit is in signal connection with the waveguide power divider. The flat panel reflector is provided with a multi-point smooth transition reflection side edge, the reflection side edge is located in the face H of the flat panel array antenna and used for performing amplitude weighting distribution on the face H of the flat panel array antenna; the waveguide power divider is connected to one end of the reflection side edge, located in the face E of the flat panel array antenna and used for performing uniform amplitude distribution on the face E of the flat panel array antenna; the antenna radiating unit comprises a rectangular waveguide and a medium grid orthogonally assembled with the rectangular waveguide. Compared with the prior art, the flat panel array antenna has the advantages of being low in loss and good in manufacturability, technical requirements are simple, and the requirement for machining precision is low.

The invention belongs to the technical field of three-dimensional sonar, and discloses a near-field wide-view-angle beam forming method of real-time three-dimensional imaging sonar. The near-field wide-view-angle beam forming method comprises the following steps that an echo sampling data matrix S of a sonar system is obtained; a time delay weighting coefficient k1 of a focusing target point inside a Fresnel time delay area and a time delay weighting coefficient k2 of the focusing target point outside the Fresnel time delay area are calculated; echo sampling data are subjected to L-point discrete Fourier transformation, and thus an echo signal S(l) is obtained; the echo signal S(l) is subjected to amplitude weighting and phase compensation, and thus a compensated echo signal tilde{S(l)} isobtained; .and the compensated echo signal tilde{S(l)} is subjected to fast Fourier transformation, an expression of the spatial beam intensity is obtained, and the spatial beam intensity is calculated. As for the situations that the focusing target point is located outside the Fresnel time delay area and located in a set imaging view angle range, the time delay weighting coefficients are optimized through a least squares method, under the premise of ensuring near-field beam forming calculation efficiency, near-field focusing accuracy can be effectively improved, and the view angle of near-field imaging is expanded.

The invention discloses an echo simulation method considering directivities of receiving and transmitting array elements. The echo simulation method of the invention comprises steps of calculating accurate echo delay time between a point target and each receiving array element, performing time delay processing on an emission signal according to echo time delay time and a wide frequency band emission signal, calculating a side visual angle of a target opposite to the transmission array element according to a position of transmitting a wide frequency band signal by the transmission array element, calculating an amplitude of directivity of the transmission array element at a signal transmission moment according to the side visual angle of the target opposite to the transmission array element, calculating a side visual angle of a target opposite to the receiving array element according to the position of receiving an echo signal in the receiving array element, calculating the amplitude of the receiving array element directivity at the moment when the echo is received according to the side visual angle of the target opposite to the receiving array element and realizing amplitude weighting of a time delay transmission signal in a range direction frequency domain according to the amplitudes of the directivity of receiving and transmitting array elements. The echo simulation method considering directivity of receiving and transmitting array elements not only realizes verification on effectiveness of an imaging algorithm, but can help to design parameters of the SAS system to be researched.

The invention discloses a ground-based radar adaptive range-amplitude weighting system and method. The method includes the steps that, firstly, a high-speed ADC module receives medium-frequency echo signal of radar and performs digital processing to the signal to acquire medium-frequency digital echo signal; secondly, an FPGA module performs digital orthogonal down-conversion processing to the medium-frequency digital echo signal, acquires baseband data and stores the same in an EMIF(expansion memory interface) of a DSP (digital signal processor); thirdly, the DSP module acquires the basebanddata stored at the last step, gains a weighting coefficient according to the baseband data, stores the weighting coefficient to the EMIF thereof; finally, the FPGA module reads the weighing coefficient from the EMIF of the DSP, and performs digital orthogonal down-conversion processing to the medium-frequency digital echo signal according to the weighting coefficient to acquire weighted baseband data, thereby achieving adaptive range-amplitude weighting. The system and method can guarantee fixed-point processing of echo in a heavy-clutter area without overflow, improve clutter base of remote light-clutter area, and further improve radar detection and false-alarm performance.

The invention provides a one-dimensional holographic antenna for a liquid crystal electronically controlled scanning gap waveguide based on amplitude weighting, which is characterized in that the upper layer of the gap waveguide is provided with a traveling wave groove for cutting off surface current so as to radiate energy to an external space, a suspended cubic block forms a high-impedance surface to guide electromagnetic waves, the surface impedance is very high in a certain frequency band, TM mode surface wave transmission and TE mode surface wave transmission are not supported, and when the excitation frequency is less than the resonant frequency, the surface impedance is inductive impedance, and TM surface waves are supported; when the excitation frequency is greater than the resonant frequency, the surface impedance is capacitive reactance, and TE surface waves are supported; when the excitation frequency is close to the resonant frequency, the surface impedance is very high, and the two modes cannot exist; multiple crystal blocks are respectively applied with external voltage for control, the antenna structure is subjected to multi-port feeding, the independent control of each feeding port on wave beams is realized by changing the liquid crystal anisotropic dielectric constant of each unit, and the high-performance requirements of applications and antenna wave beam scanning in a high-frequency-band electronic communication system are met.

The invention discloses an OFDM system peak power optimization method based on block interleaving and a transmission system thereof. The OFDM system peak power optimization method comprises the stepsof: generating a binary sequence by utilizing a binary random sequence generator module, and mapping the binary sequence into a base band frequency domain signal sequence SA and a base band frequencydomain signal sequence SB respectively by utilizing a mapping A module and a mapping B module; respectively carrying out blocking processing on the base band frequency domain signal sequences SA and SB to obtain sequences XA and XB after blocking processing; carrying out repeated block interleaving on the XA and the XB which are obtained after blocking processing to obtain a plurality of differentsequences Ai and Bj; respectively carrying out IFFT (Inverse Fast Fourier Transform) on the plurality of different sequences Ai and Bj to obtain a plurality of different candidate signals ai and bj,i.e., a first part of candidate signals; carrying out adding and amplitude weighting processing on a plurality of different candidate signals ai and bj in the first part of candidate signals to obtaina plurality of new candidate signals, i.e., a second part of candidate signals; and from all the candidate signals, selecting a candidate signal with the minimum PAPR value to carry out transmission.

The invention discloses a photon two-dimensional convolution acceleration method and system based on time-wavelength interleaving, and the method comprises the steps: firstly, loading a to-be-convolved signal to a multi-wavelength optical signal containing M * N wavelengths, and dividing the multi-wavelength optical signal into M sub-optical signals each containing N wavelengths through a wavelength division demultiplexer; the M sub optical signals are sent to the delay weighted micro-ring array after being sequentially increased with equal interval delays, and coupling coefficients of M * N micro-rings in M delay weighted micro-ring units in the delay weighted micro-ring array are controlled to achieve amplitude weighting of M * N wavelength signals respectively; the M sub-optical signals after amplitude weighting are subjected to wavelength division multiplexing to form a composite optical signal, and then photoelectric conversion is completed to obtain a corresponding characteristic signal. According to the method, light is used as an information carrier, two-dimensional convolution kernel convolution acceleration operation of two-dimensional data can be realized in a single signal period based on two-stage delay and two-dimensional micro-ring array weighting, and the speed and the energy efficiency ratio of convolution operation are greatly improved.