46 results about "Orthogonal complement" patented technology

The invention discloses an ADS-B deception jamming restraining method based on a cross array. The method includes: using an ADS-B receiving machine to analyze the target identity information and air position information received by a central array element of an antenna array; converting the target position information into the target azimuth angle and pitching angle further by the aid of the position of the receiving machine; projecting the received data to the orthogonal complement space of a target, and restraining the signals, with the coming direction of (theta, phi), in the data received by the antenna array; using the ADS-B receiving machine to process the data after orthogonal projection, and identifying the identify information of the target; judging the actual target and deception jamming according to a deception jamming judging algorithm, and the like. After jamming identification and restraining by the method, the ADS-B receiving machine can obtain real ADS-B signals through demodulation, deception jamming is restrained, and airspace monitoring is achieved.

Generation of a transformed Interim Connection Space for spectral data is provided. A first Interim Connection Space for spectral data in a full spectral space is accessed. A first map, which characterizes a linear transformation from the full spectral space to a first color space, is accessed. A second map, which characterizes a linear transformation from the first Interim Connection Space to the first color space, is determined. The first Interim Connection Space is decomposed into orthogonal subspaces, the orthogonal subspaces including a first subspace that is a null space of the second map and a second subspace that is an orthogonal complement of the null space in the first Interim Connection Space. The transformed Interim Connection Space is generated based on the first subspace and the second subspace.

Codewords encoded using non-coherent codes and received at a receiver via non-coherent channels in a multi-input, multiple output (MIMO) network using orthogonal frequency demultiplexing (OFDM) are decode by concatenating multiple adjacent codewords of a received signal into a superblock at the receiver. A projector matrix based on a codebook is predetermining. Each codeword in the superblock is projected onto an orthogonal complement of a correspond transmitted codeword using the projector matrix to obtain a corresponding distance metric of a generalized likelihood ratio test (GLRT) codeword. A minimal distance metric is selected to obtain an estimate of the transmitted codeword corresponding to a transmitted signal.

The invention relates to a self-coherent MUSIC algorithm-based global positioning system interference suppressing method, which is implemented by combining subspace projection and routine beam forming technology. The method comprises the following steps: projecting signals received by an array antenna to an interference orthogonal complement space; for the projected data, estimating the satellite signal coming direction by utilizing a self-coherent MUSIC algorithm; and performing beam forming on the projected data by utilizing the estimated satellite signal direction. By combining the subspace projection and the routine beam forming technology, the method is a secondary anti-interference method; firstly, the interference is suppressed by utilizing a projection matrix of the interference orthogonal complement space; and secondly, satellite signals are strengthened by utilizing the routine beam forming technology. In the process of strengthening the satellite signals by utilizing the routine beam forming technology, for the projected data, the satellite signal coming direction is estimated by utilizing the self-coherent MUSIC algorithm, and the routine beam forming is performed by utilizing the estimated satellite signal direction. Through the method, interference suppression is realized, the satellite signals are ensured to be not attenuated, an inertial navigation auxiliary unit is not needed, and the method has high estimation accuracy and high resolution ratio.

The invention discloses a multiclass satellite navigation interference suppression method based on solution expanding technology. The method comprises the steps as follows: projecting the signal received by the array antenna to the interference orthogonal complement space for restraining the blanket jamming, calculating the solution expanding weight vector matrix for the projected data, judging whether the matrix is full rank for identifying the deception jamming. If having deception jamming, calculating the solution expanding weight vector dependency, identifying the number of deception interference source, the deception interference source comprises fake satellite signal and true satellite signal. Using the solution expanding weight vector of the deception jamming for forming the rectangular projection matrix of the deception jamming, having the projection restraining deception jamming on signal, using the weight vector of true satellite for forming multi-wave beam and obtaining the signal processing gain. The method can generate high gain multi-wave beam with suppress interference, transmitted deception jamming and generated type deception jamming resisting capability, the multi-wave beam forming capability is not limited by the array element, and there is no need to know the satellite signal and interference information.

Mapping spectral colors in an Interim Connection Space (ICS) of a full spectral space based on an objective function is provided. A spectral color value in the ICS is accessed, and a spectral gamut boundary of the destination gamut is accessed. The spectral color value is mapped into mapped spectral color value based on minimization of an objective function of coordinates of a first subspace of the ICS, by fixing coordinates of a second subspace of the ICS, subject to a constraint that a result is within the spectral gamut boundary. The first subspace is a null space of a transformation from the ICS to a color space, while the second subspace is an orthogonal complement of the first subspace in the ICS. The constraint is determined by a gamut section that is an intersection of the spectral gamut in the ICS and an affine subspace characterized by the fixed coordinates of the second subspace.

A method for decoding data symbols modulated with a corresponding codeword from a constellation set of codewords expands the constellation set of codewords with a set of basis functions to produce a basis-expanded constellation set and projects projecting a received modulated data symbol onto orthogonal complements of the basis expanded constellation set to obtain a set of distance metric of a generalized likelihood ratio test (GLRT) for each codeword of the constellation set. The set of basis functions includes a Fourier exponential basis function in a frequency domain, a Legendre polynomial basis function in a time domain, and a Fourier-Legendre product basis function in the frequency domain. The method selects a codeword corresponding to a minimal distance metric or a maximal correlation metric and decodes the data symbol from the received modulated data symbol using the codeword.

The invention discloses a continuous pre-coding and user selection united algorithm for a multi-user MIMO (Multiple-Input Multiple-Output) broadcast channel. According to the continuous pre-coding and user selection united algorithm for the multi-user MIMO broadcast channel, a normalization projector vector of orthogonal complement space which is formed between all pre-coding vectors which do not select users and all pre-coding vectors which select users is served as a new pre-coding vector of users; user selection is performed according to a signal to interference plus noise ratio of every user; one user is selected at one time until a preset user number is achieved, and accordingly an optimal pre-coding vector of every user is achieved. Compared with the traditional method, the continuous pre-coding and user selection united algorithm for the multi-user MIMO broadcast channel has the advantages of being low in complexity, effectively suppressing multi-user interference, improving channel capacity and effectively improving system performance under the conditions that the number of users if large and the signal to interference plus noise ratio is large.

The invention discloses a robust estimation method of a direction of arrival (DOA), by which quite high estimation precision can be obtained. The method specifically comprises: sequentially dividing an equidistant linear array into three sub-arrays from the left to the right, i.e., a forward auxiliary array, a central main array and a backward auxiliary array respectively; dividing the central main array into a front half portion and a rear half portion according to a certain rule; then calculating a covariance matrix Rforward between the front half portion and the backward auxiliary array and a covariance matrix Rbackward between the rear half portion and the forward auxiliary array; performing singular value decomposition respectively on the Rforward and the Rbackforward, and extracting the orthogonal complement of the subspace of far-field signals received by the equidistant linear array from a singular value decomposition result; and establishing a DOA estimation operator by use of guiding vectors between the orthogonal complement and the front half portion and the rear half portion, performing search on the DOA estimation operator by use of a minimum parameter search method to obtain K minimum value points, and through the search, obtaining theta 1 to theta k of each minimum value point as k DOAs of the far-field signals.

The invention discloses an interference coordination-based inter-cell user scheduling method. The method comprises the following steps of: determining a target user, and acquiring a space signature of the user in a cell where the user is located; generating an orthogonal complement space of an interface space; searching the user of the space signature in the orthogonal complement space; and searching a schedulable user. The interference coordination-based inter-cell multi-user scheduling method disclosed by the invention not only needs no base station exchange information, but also effectively inhibits inter-cell interferences and improves the utilization ratio of wireless channel resources.

The invention discloses a submatrix-level OP wave beam forming method based on covariance matrix normalization. The method can be used to effectively inhibit interference, make a main lobe of a self-adaptive directional diagram conformal, reduce side lobes the self-adaptive directional diagram and obtain higher output SINR and convergence speed. The method comprises that submatrix-level reception signals are normalized, and a corresponding normalized sampling covariance matrix is calculated; the amount of interference signal sources is estimated by utilizing the MDL criterion, and further an interference subspace is obtained; and finally, the static weight vector is projected to an orthogonal complement space of the interference subspace to obtain a self-adaptive weight vector.

The invention relates to a global position system (GPS) interference suppression method based on multichannel one-way delay mutual correlation processing, which is realized by combining space projection and a conventional beam forming technology. Firstly, an interference orthogonal complement space projection array is utilized to restrain interference, and secondly, the conventional beam forming technology is utilized to enhance a satellite signal, i.e. an autocorrelation CLEAN algorithm is utilized for the data after projection to estimate the incoming direction of the satellite signal, and the estimated satellite signal direction is utilized to carry out conventional beam formation. The method comprises the following steps of: projecting the signals received by an array antenna to the interference orthogonal complement space; estimating the incoming direction of satellite signal by utilizing the autocorrelation CLEAN algorithm for the multichannel delay data after projection and thearray data after projection; and forming the beam for the data after projection by utilizing the estimated direction of the satellite direction. The invention ensures zero decrement of the satellite signal, does not need an inertial navigation auxiliary unit, is simple to realize, enables the main lobe of an array directional diagram to aim at each satellite signal and is suitable for any arrays,and in addition, the estimation of the satellite signal direction is not limited by the array element number.

The invention discloses a multi-value chain collaborative evaluation system and method based on spatial decomposition enhancement, and aims at a scene in which an evaluated person participates in evaluation of a plurality of evaluation systems in sequence, under the condition of information asymmetry, according to sub-linear spaces formed by weight vectors in the first (n-1) evaluation systems and orthogonal complement spaces of the sub-linear spaces, projecting a weight vector vector sub-linear space and an orthogonal complement space of the nth evaluation system, performing linear decomposition on the projection of the sub-linear space by using a base formed by a maximum linear irrelevant group of a weight vector, quantitatively calculating an enhancement multiple, and enhancing the winner in the first n-1 evaluations, so as to partially realize the restoration of the hidden information, and the objectivity of the nth evaluation and the overall level of the winner are improved.