17 results about "Radar altimeter" patented technology

The invention relates to the technical field of ocean new energy technology utilization, and discloses an oscillating water column type wave energy power generation system with an energy gathering structure at the bottom, which comprises a jacket, an air chamber, a turbine power generation system, a radar altimeter, an infrared camera, an airflow velocity sensor, a control host and a bottom energy gathering assembly, the bottom energy-gathering assembly is installed at the lower end of the air chamber and provided with a transmission mechanism, reflection and diversion of seawater at the bottom of the air chamber are achieved through the arranged horizontal bottom plate and the two symmetrically-arranged energy-gathering plates, energy gathering beyond the width of the air chamber is completed, and opening and closing of the energy-gathering plates are synchronously controlled through the transmission mechanism. And the amount of seawater flowing into the air chamber from the water inlet is changed. According to the wave energy power generation system, the oscillation intensity of the water column in the air chamber can be adjusted according to changes of sea surface waves, the speed of the generated air flow can be matched with the optimal working frequency of the turbine power generation system, the power generation efficiency of the device is guaranteed, and the oscillation water column type wave energy power generation device can be protected and prevented from being impacted by sea waves.

The invention belongs to the technical field of multi-source remote sensing image fusion, and relates to a structure-texture collaborative interference radar altimeter image and optical image fusion method and system. The method comprises the following steps: reading an optical image and a wide-swath interference radar altimeter image, and carrying out preprocessing and space-time registration; respectively decomposing the registered optical image and radar altimeter image into a structural layer and a texture layer by adopting a multi-scale local total variation decomposition method; fusing the structure layer by adopting a fusion rule based on weighted local energy and local gradient consistency to generate a fused structure layer; fusing the texture layer by adopting a fusion rule of combining partition filtering and maximum absolute value to generate a fused texture layer; adding the fusion structure layer and the fusion texture layer, and reconstructing to obtain a gray fusion image; and performing intensity-hue-saturation inverse transformation with the chromaticity and the saturation of the original optical image by taking the gray level fusion result as intensity to generate a final natural color fusion image.

In order to help pilots relying on manual visual inspection to realize autonomous landing more safely, the invention provides a method for assisting autonomous landing by using an airborne Doppler navigation radar and an airborne radar altimeter. Firstly, the glide speed can be obtained by directly utilizing the existing speed detection data of the airborne Doppler navigation radar. And secondly, calculating an inclination angle in a vertical plane by using detection data of Doppler frequency shift by a Doppler navigation radar, thereby obtaining a glide angle. Or the glide angle is calculated according to the trigonometric function relation by using the three-dimensional velocity component measured by the airborne Doppler navigation radar. And then on the basis of acquiring height measurement data by using an airborne radar altimeter, calculating a glide distance by using the acquired glide angle and a trigonometric function relationship. Furthermore, if the aircraft is further provided with a flight management system, an automatic driving system and the like, technical support can be provided for semi-automatic landing by using landing data provided by an airborne Doppler navigation radar and a radar altimeter.

The invention belongs to the technical field of radar altimeters, and particularly discloses a sea-skimming flight altimeter high and low speed equivalent test method and system. The method comprises the following steps: determining test conditions including a flight path, flight times and a preset flight speed; controlling the test aircraft to perform a flight test according to the test conditions; in the test process, sea height data are collected according to a preset equivalent speed multiple, and equivalent height data are obtained. According to the scheme, the technical problem that height measurement of an altimeter in sea-skimming flight under various speed conditions cannot be realized when the flight speed of an aircraft is limited is solved.

The invention discloses a radar altimeter data processing method and device and a storage medium, and relates to the technical field of radar altimeter data processing. The method comprises the following steps: carrying out processing and target detection on all echo signals to obtain potential target points; dividing M pulse echo data in one frame into a plurality of data segments with different accumulation lengths; for each potential target point, calculating coherent accumulation energy of the potential target point in each data segment; according to the change rule of coherent accumulation energy of the potential target points among the data segments, incoherent interference target points are discriminated and filtered out; sorting the residual target points after filtering according to energy, and selecting Q target points with the highest energy for tracking; and comparing the energy of each target tracking chain in the historical frame, and taking the distance value corresponding to the target tracking chain with the highest energy as the final output value of the radar altimeter. According to the invention, data jump is greatly suppressed from a data source, and the problem of lack of capability of suppressing power supply fluctuation and electromagnetic interference is solved.

The invention relates to a multi-source information fusion navigation method in a landing process of a reusable carrier rocket, aiming at the characteristics that when the reusable carrier rocket is close to a target landing point, because the flight height is relatively low and various positioning single machines can be utilized, the method comprises the following steps of: firstly, utilizing rocket body speed and position information output by a differential receiver; the rocket body speed and position information solved by the strapdown inertial measurement combination is corrected, and landing navigation control of the carrier rocket is carried out by using a corrected result; and when the output of the differential receiver cannot be utilized, the measurement result of the radar altimeter is further utilized to correct the rocket body height information solved by the strapdown inertial measurement combination, and the corrected height information is utilized to carry out landing navigation control on the carrier rocket. The method can ensure that the rocket navigation system can always output high-precision and high-reliability position and speed information in the landing process.

The invention relates to the technical field of remote sensing image processing, in particular to a dark water body detection and compensation method and system in a wide swath interference radar altimeter image. The method comprises the following steps: acquiring a wide-swath interference radar altimeter image and an optical remote sensing image which are subjected to geometric registration in the same area; initial water body areas are extracted from the radar altimeter image and the optical image respectively, and a radar water body mask and an optical water body mask are generated; comparing the radar water body mask with the optical water body mask through logical operation, identifying a region which is a water body on the optical image and presents non-water body characteristics on the radar image, and defining the region as a'dark water 'region; compensation model construction: establishing a statistical distribution model based on the back scattering intensity of the identified normal water body area in the radar altimeter image; and calculating a reasonable compensation amount for the identified dark water region by using the established statistical distribution model, enhancing the pixel intensity of the region, and generating a compensated radar image.

According to the real-time pose measurement method provided by the invention, optical beacons distributed in a three-dimensional space are used as target spots, an optical detection and processing module arranged on a rocket is used for real-time calculation, and a rocket-borne radar altimeter is combined, so that pose information of a rocket body in the whole stage of a recovery process can be acquired in real time. According to the method, an on-rocket optical pose measurement method and a radar height measurement method are combined, high-precision pose information is continuously obtained, compared with traditional integrated navigation positioning, the method has higher precision and higher adaptability, and a precise pose measurement result is provided for guiding recovery landing of a rocket; according to the invention, an optical pose measurement mode is added in a rocket landing section, so that the defects that an inertial navigation method has accumulated errors and a single-point navigation method is relatively low in precision are overcome, and the requirement of continuously acquiring high-precision pose measurement information is met; the invention provides a working process and an implementation method for combined use of inertial navigation equipment, navigation equipment, optical positioning and a radar altimeter, and the operability of rocket recovery is powerfully improved.

This invention relates to the field of marine new energy technology utilization, and discloses an oscillating water column wave energy generation system with a bottom-mounted energy-concentrating structure. The system includes a jacket, an air chamber, a turbine power generation system, a radar altimeter, an infrared camera, an airflow velocity sensor, and a control unit. It also includes a bottom energy-concentrating component installed at the lower end of the air chamber and equipped with a transmission mechanism. A horizontal bottom plate and two symmetrically arranged energy-concentrating plates reflect and guide seawater at the bottom of the air chamber, concentrating energy beyond the width of the air chamber. The transmission mechanism synchronously controls the opening and closing of the energy-concentrating plates, changing the amount of seawater entering the air chamber at the inlet. This wave energy generation system can adjust the oscillation intensity of the water column in the air chamber according to changes in sea waves, ensuring that the generated airflow velocity matches the optimal operating frequency of the turbine power generation system, guaranteeing the power generation efficiency of the device. It also protects the oscillating water column wave energy generation device from wave impacts.

A radar altimeter is described herein comprising a transmitting antenna (11) and a receiving antenna (12), wherein said transmitting antenna is configured to transmit a first radio frequency “RF” signal (13) and wherein said first RF signal (13) is configured to be reflected back to said radar altimeter as a second, corresponding reflected signal (14). The receiving antenna (12) is configured to receive said second, corresponding reflected signal (14). The radar altimeter further comprises an antenna radome (60) provided relative to said transmitting antenna (11) and said receiving antenna (12) such that said first RF signal (13) passes through said radome (60) after being transmitted from said transmitting antenna (11) and wherein said second, reflected RF signal passes through said FSS radome before being received by said receiving antenna (12). The radome comprises a frequency selective surface “FSS” antenna radome (60).

The application discloses a kind of narrow river detection methods suitable for spaceborne wide swath interferometric radar altimeter image, comprising: reading into spaceborne wide swath interferometric radar altimeter image;It is enhanced river linear feature by Gaussian difference preprocessing to suppress background;Curvature structure perception detector is constructed, curvature response map is calculated based on Hessian matrix eigenvalue, and feature fusion enhancement is carried out in conjunction with multi-direction structure consistency score;The binary image obtained by adaptive threshold segmentation based on local statistics is used as region label by carrying out adaptive threshold segmentation to enhanced feature map, maximum value is extracted in the region corresponding to enhanced feature map, seed point set is formed, and adaptive region growth based on queue priority is executed, to generate initial river center line;Markov random field model is introduced, global structure optimization and topological connectivity correction are carried out using graph cut algorithm, to obtain optimized river center line;Direction and radiation characteristic constraint is applied again, morphological dilation is carried out, and finally complete river mask is generated.

Embodiments of the disclosure provide for improving alignment of a vehicle to a landing site. In the context of a method, the method includes generating transmission signals via a radar altimeter onboard a vehicle, the vehicle being oriented proximate to a landing site comprising a plurality of radio-reflective targets; receiving, via the radar altimeter, a plurality of reflected signals; generating a plurality of power metrics based on the plurality of reflected signals; comparing the plurality of power metrics to a threshold to determine a subset of power metrics associated with the radio-reflective targets; generating alignment correction data based on respective difference values between the subset of power metrics; and causing output of the alignment correction data to a ground station or a control system onboard the vehicle, wherein the alignment correction data comprises at least one parameter for aligning the vehicle with the landing site to minimize the difference values.

This invention relates to the field of airborne geophysical exploration, and more particularly to an intelligent monitoring and predictive guidance method for helicopter-towed pods. This method involves arranging multiple GPS arrays on the flexible structure of the pod, fusing airborne GPS, radar altimeter, attitude sensor, video, and meteorological data to construct a pod oscillation model incorporating structural modes and identifying deformation parameters online. A multi-model adaptive fusion framework is established, employing extended Kalman filtering and a Bayesian weight update mechanism to achieve state estimation. The spatial wind field gradient is inverted and injected into the forced pendulum dynamics equation to predict the trajectory, calculating the ground contact risk index to trigger graded alarms. Pilot cognitive load is assessed based on eye-tracking and joystick spectral analysis, dynamically simplifying the guidance interface. Lateral / longitudinal oscillation patterns are identified in the body coordinate system, generating differentiated control commands. This invention achieves intelligent monitoring and predictive guidance of the pod's state, improving flight safety and data quality.

The invention discloses a narrow river detection method suitable for a satellite-borne wide-cradling interference radar altimeter image. The method comprises the following steps: reading in the satellite-borne wide-cradling interference radar altimeter image; gaussian difference preprocessing is carried out to suppress background and enhance the linear features of the river channel; constructing a curvature structure sensing detector, calculating a curvature response diagram based on a Hessian matrix eigenvalue, and performing feature fusion enhancement in combination with a multi-direction structure consistency score; performing self-adaptive threshold segmentation based on local statistics on the enhanced feature map to obtain a second map as a region mark, extracting a maximum value in a corresponding region of the enhanced feature map, forming a seed point set, executing self-adaptive region growth based on queue priority, and generating an initial river channel center line; introducing a Markov random field model, and performing global structure optimization and topological connectivity correction by using a graph cut algorithm to obtain an optimized river channel center line; and then applying direction and radiation characteristic constraints, performing morphological expansion, and generating a final complete riverway mask.

The application discloses a radar altimeter data processing method and device and a storage medium, and relates to the technical field of radar altimeter data processing. The method comprises the following steps: processing all echo signals and target detection to obtain potential target points; dividing M pulse echo data in a frame into multiple data segments with different accumulation lengths; calculating the coherent accumulation energy of each potential target point in each data segment; judging and filtering out non-coherent interference target points according to the change rule of the coherent accumulation energy of the potential target points among the data segments; sorting the remaining target points after filtering according to energy, and selecting the Q target points with the highest energy for tracking; comparing the energy of each target tracking chain in historical frames, and taking the distance value corresponding to the target tracking chain with the highest energy as the final output value of the radar altimeter. The application greatly suppresses data jumping from the data source, and solves the problem of lacking power supply fluctuation and electromagnetic interference suppression capability.

This invention belongs to the field of remote sensing mapping and marine surveying technology. Specifically, it relates to a vertical deviation gridding method based on waveform retracking quality weighting. The method includes: Step 1) performing waveform retracking on the 20Hz echo raw waveform data in the radar altimeter SGDR data to obtain the 1Hz accuracy, latitude, and distance measurements and their corresponding waveform retracking quality parameters, thereby obtaining the sea surface height; Step 2) calculating the residual vertical deviation ε along the trajectory. res And its corresponding longitude and latitude; Step 3) Calculate the signal cross-covariance matrix C in the LSC algorithm. ξε C ηε and C εε Step 4) Based on the waveform retracking quality parameters corresponding to the 1Hz distance measurement obtained in Step 1), calculate the noise covariance matrix C in the LSC algorithm. nn Step 5) According to C nn , and C εε C ξε and C ηε Using the LSC algorithm, the residual vertical deviation ε along the trajectory obtained in step 2) is... res Gridding is used to obtain high-precision vertical deviation grid data based on waveform quality weighting.