10 results about "Aperture synthesis" patented technology

The invention relates to a two-dimensional staggered array MIMO (Multiple Input Multiple Output) radar system for monitoring dynamic deformation of a bridge, which realizes decoupling of spatial resolution and time resolution by adopting a two-dimensional staggered array MIMO radar hardware architecture and replacing traditional mobile synthetic aperture with static virtual aperture synthesis through integrated design. According to the system, a continuous virtual area array is synthesized through transmitting and receiving arrays which are in non-uniform sparse arrangement, and high-resolution three-dimensional imaging of a bridge monitoring area is realized in combination with an FMCW signal processing and near-field three-dimensional imaging algorithm; and carrying out pixel-level processing on the serialized three-dimensional complex image by using a rapid time sequence interference and deformation extraction module to obtain a high-precision deformation sequence. The method does not need a mechanical scanning part, has the advantages of high environmental robustness, low hardware cost, flexible deployment and the like, and can provide panoramic and high-precision four-dimensional dynamic deformation field data for bridge structure state evaluation.

The invention discloses a high signal-to-noise ratio detection system and method based on superlens array aperture synthesis, the system comprises a superlens array and a registration module, the superlens array comprises a substrate and N sub-superlenses integrated on the substrate, and the N sub-superlenses are used for forming N sub-images on a camera target surface for the same target; and the registration module is used for registering the N sub-images, and superposing the registered N sub-images frame by frame to obtain an image after aperture synthesis. According to the detection system, the signal-to-noise ratio of a target can be improved, high-resolution detection is realized, and miniaturization and integration can also be realized.

The present invention relates to a method for operating a target detection radar according to a first operating mode and at least one second operating mode, the first operating mode being a synthetic aperture radar imaging mode and each second operating mode being different from the first operating mode, the method comprising the implementation of several recurrences of a signal transmission / reception step, each recurrence of said step comprising the following sub-steps: - generation of a sequence of consecutive pulses, each pulse of the sequence being associated with a respective operating mode, - transmission of the pulses in different frequency bands, and - reception in a common time window of the echoes of the pulses, during the transmission sub-step of each recurrence, at least one of the pulses, called the phase-shifted pulse,being emitted with a random phase associated with the number N.,

The application discloses a phased array radar high-resolution imaging method based on truncated singular value decomposition, which comprises the following steps: firstly, measuring the radiation intensity of each angle of an antenna to obtain a directional diagram function for Toplitz transformation, and constructing a corresponding Toplitz matrix; then, measuring the echo signal power and the noise power of a system and calculating the signal-to-noise ratio of the system; and finally, performing singular value decomposition on the Toplitz matrix, arranging the singular values from large to small, combining a singular value processing strategy, and completing the high-resolution imaging of the phased array radar. The method effectively solves the problems of poor robustness, strong parameter dependence and high operation complexity of the existing deconvolution imaging method under the condition of low signal-to-noise ratio, reduces the algorithm complexity, suppresses the noise influence, has strong robustness, has unique advantages in the imaging scene of a forward-looking radar, and is suitable for the forward-looking imaging task of the phased array radar and can be popularized to other radar scenes with insufficient direction angle resolution or limited aperture synthesis.

This invention discloses a distributed laser-induced acoustic communication method and system based on dynamic virtual aperture synthesis, belonging to the field of cross-medium communication technology. The method constructs a distributed self-organizing network using multiple airborne nodes, establishing a unified coordinate system and a global synchronous clock; it senses sea conditions and atmospheric parameters in real time, plans the equivalent emission aperture size as needed, and uses a sparse array algorithm to select nodes to form a dynamic virtual emission array; it calculates the cross-medium propagation phase compensation amount by combining node position deviations and the influence of sea surface waves; and it achieves precise coordinated emission of laser pulses by nodes relying on the global clock, synthesizing highly directional acoustic signals in underwater target areas through photoacoustic effects. This invention overcomes the limitations of single-platform physical aperture and energy, utilizes distributed collaboration to achieve large-aperture virtual synthesis, effectively improving laser-induced acoustic communication distance, signal-to-noise ratio, and anti-interference capability, and possesses good network self-healing and task adaptability.

This application relates to the field of adaptive optics technology, and in particular to a digital aberration correction method and apparatus for meta-imaging optical imaging. The method includes: acquiring multi-view images collected by a meta-imaging optical system; calculating the two-dimensional offset relationship between images from different viewpoints in the multi-view images, and obtaining an offset matrix based on the two-dimensional offset relationship; obtaining an aberration matrix based on the offset matrix through two-dimensional integration; generating a new offset matrix using the aberration matrix, and performing digital offset correction on the multi-view images using the new offset matrix; and obtaining a high-resolution two-dimensional image after aberration removal using an aperture synthesis algorithm. This solves the technical problems in related technologies, such as the need for supplementary hardware support for deflection correction, resulting in a large optical system size and slow imaging speed, causing system calibration errors, significantly reducing imaging performance, and making it unsuitable for faster and more complex imaging environments.

The invention discloses a novel ground distributed optical synthetic aperture direct imaging method and device. The device comprises a plurality of sub-telescopes, a K mirror, a delay line, an entrance pupil mechanism and a light combination telescope. According to the invention, direct imaging is realized by ensuring the pupil mapping relation, and the imaging field of view is larger than that of a non-common-frame Michelson interference array; more complete spatial frequency sampling is carried out on a celestial body target by means of earth rotation and using a small number of small-caliber telescopes, the frequency signal acquisition efficiency is higher than that of a non-common-rack Michelson interference array, and imaging can be carried out on a complex surface source. According to the invention, by adopting the layout that the sub-telescopes are distributed on the ground, compared with a common-frame Fizeau interference array, the length of a base line is not limited by the size of a frame, and higher-resolution imaging can be realized.

The application discloses a multi-aperture coherent synthesis optical phased array laser communication device and method, belongs to the technical field of laser communication, and solves the technical problem that in the prior art, due to the fact that a single phase compensator is relied on to perform centralized phase regulation on all input light beams, and when long-distance transmission is performed, the wavefront distortion is caused by the influence of atmospheric turbulence, it is difficult to accurately match the phase difference of each light beam in real time, and the far-field coherence of a synthesized light beam is significantly reduced. The laser communication device is constructed, a multi-aperture coherent light synthesis unit cascade architecture is adopted, a signal transceiving logic is reconstructed by using a multi-beam interference and a synthesis aperture principle, the light path coupling of the multi-aperture is completed, the phase of each coherent light synthesis unit is accurately regulated, and high-quality communication is realized. The application is used for realizing dynamic tracking and compensation of rapid random phase fluctuations caused by turbulence, and efficient and accurate coherent aperture synthesis.

The invention discloses an array aperture virtual synthesis and angle resolution improvement method. According to the invention, the second receiving array of which the array element spacing is equal to the aperture size of the first receiving array is designed, and the phase center displacement processing is carried out on the first receiving array signal based on the array element coordinates of the second receiving array, so that the equivalent large-aperture array with M * N * K * L virtual array elements is synthesized by only using M * N + K * L physical array elements; therefore, on the premise that a multi-channel orthogonal waveform does not need to be transmitted, the angular resolution of the system is greatly improved, and meanwhile, the hardware complexity, the waveform resource overhead and the engineering implementation difficulty of the radar system are remarkably reduced.

This invention relates to a method for detecting high-reflectivity freeform surfaces based on wide-field multi-aperture synthetic phase deflection. The method includes: constructing a multi-camera phase deflection system using a surface to be measured, a screen for projecting a predetermined pattern onto the surface, and multiple cameras for simultaneously capturing different regions of the surface; each camera's imaging area serving as an aperture; acquiring the distortion patterns reflected by all apertures from the surface, and calculating the correspondence between camera pixels and display screen pixels; selecting multiple sets of reference points within overlapping areas of different apertures, calculating the three-dimensional absolute coordinates of these reference points to obtain an aperture surface shape distribution with absolute depth; and stitching together all aperture surface shape distributions to obtain the complete three-dimensional morphology of the surface to be measured. Compared with existing technologies, this invention can achieve accurate detection of large-area slope mirror elements and has advantages such as non-scanning detection and non-zero detection.