3 results about "Plane wave" patented technology

The invention relates to a space-borne microwave atmospheric sounding instrument, which comprises feed sources, calibration bodies, a motor, plane mirrors, parabolic reflectors, a scanning drive control module, multiplexers and receiver units. The motor is controlled by the scanning drive control module to drive the plane mirror to rotate. The plane mirrors reflect received electromagnetic wave signals to the parabolic reflectors in the form of plane waves by scanning the atmosphere and the calibration bodies. The parabolic reflectors realize secondary reflection to enable the plane waves to be reflected to the corresponding feed sources arranged opposite thereto. The multiplexers are used for separating the frequency of the electromagnetic wave signals received by the feed sources respectively. Each receiver unit comprises a plurality of receivers parallel with the output end of the corresponding multiplexer, and is used for receiving the electromagnetic wave signals matched with the frequency thereof. The space-borne microwave atmospheric sounding instrument has the advantages of being high in performance, high in integration, low in weight and low in power consumption.

Provided are a method and device for ultrasonic imaging by synthetic focusing. The method comprises: exciting a plurality of matrix elements of an ultrasonic probe to transmit plane waves many times, wherein transmitting apodizations at the time of every transmission of the plane waves by the plurality of matrix elements correspond to the respective lines in a measurement matrix in which elements are randomly distributed; after every transmission of the plane waves, exciting all the matrix elements of the ultrasonic probe to receive echo signals, in order to obtain channel data; recovering a synthetic focusing channel data set by use of a compressed sensing reconstruction algorithm according to a channel data set and the measurement matrix; and subjecting the synthetic focusing channel data set to beamforming so as to generate an ultrasonic image.

The invention discloses a designing method of a vortex beam mask with an oblique-line compressed phase step. The method comprises the steps a remainder resolving function, a plane wave factor and a binary radial cut-off factor are combined to obtain a transmittance function T of the vortex beam mask, and the vortex beam mask with the oblique-line compressed phase step is obtained by substituting different selected parameter values of m, K and a1 into the transmittance function T. The vortex beam mask with the oblique-line compressed phase step can be generated through the mask produced by thedesigning method. The singularity of the vortex beam mask with the oblique-line compressed phase step is spirally distributed, the spiral level of the arrangement of the singularity is controlled by the gradient of a compressed oblique line, an unprecedented novel optical field mode distribution is provided, and the method has significant application value in the field of particular manipulating.