CN1064129C - Apparatus and method for remote sensing multi-dimension information integration - Google Patents

Abstract

A remote sensing multi-dimensional information integration device and method, is that the aircraft optical machine scanning imager, the optical machine scanning laser range finder and the attitude measurement device are jointly arranged on a rigid platform, and the imager and the main laser range finder The optical paths are combined together to form a range-finding imaging combined remote sensor. Use the synchronous controller coaxial with it to control the said range-finding imaging combination remote sensor, attitude measuring device, and GPS receiver, so that image data, position data, distance data, and attitude data are provided synchronously and after being processed, they can be directly Obtaining multi-dimensional remote sensing series images can shorten the operation cycle and greatly improve efficiency.

Description

Device and method for remote sensing multi-dimensional information integration

The invention belongs to the technical field of remote sensing and earth observation, and in particular relates to a device and a method for making multi-dimensional remote sensing series images with remote sensing technology.

In the field of remote sensing and earth observation technology, there are two existing technologies, that is, the generation technology of geoscience coding remote sensing image and the generation technology of ground digital elevation model. Among them, the generation technology of geo-coded remote sensing images is to transform and resample the images containing various distortions obtained by aerospace and aviation remote sensors, and convert them into geo-coded remote sensing images rearranged according to the geographic coordinate grid. There are several steps to realize it with the existing technology: collect the existing topographic map within the scope of the remote sensing image: compare the remote sensing image with the topographic map, select common points (or points with the same name) on the remote sensing image and the topographic map respectively, and at the same time Read out the line number, pixel number (L.I), and geographical coordinates (X, Y, Z) of the public point; use the mathematical model to establish the transformation relationship model between the image space and the geographical space according to the coordinates of the public point; according to the coordinate grid The remote sensing image is resampled according to the sampling model to complete the remote sensing geoscience coding image.

The generation technology of the ground digital elevation model (DEM) is to give height data (elevation) at each point, and the two-dimensional lattice of these points arranged in a geographic coordinate grid to express the ground's ups and downs is called the ground digital elevation. model (DEM). The methods of generating DEM in the prior art include:

Stereo photogrammetry is used to generate topographic maps at the same time, which is a technology that has become an industry at home and abroad. Digitalization of topographic maps to generate DEM is a popular existing technology. And ground measurements directly generate DEM.

The realization of the above two technologies itself is a technical process that requires a long cycle and a large amount of labor input. In remote sensing image processing, DEM must be integrated with remote sensing geoscience coded images, which is the main technical measure to improve the accuracy of remote sensing classification. This combination must go through the establishment of the conversion relationship model and the re-sampling process between the two. However, due to the complexity of the above-mentioned technical process, it is far from being used in the actual remote sensing operation process.

Among the existing technologies in the aviation and aerospace remote sensing information acquisition technology system, the integrated technologies are:

Combination of a single remote sensor and a Global Positioning System (GPS) receiver:

One is the combination of remote sensors such as GPS receivers and optical-mechanical scanning imagers. To reduce the difficulty of image positioning:

One is the combination of aerial camera and GPS receiver. The GPS receiver provides the position of the projection center of the aerial camera at the moment of exposure, and the block adjustment method is used to encrypt the mapping control points to reduce the ground survey work. This technology already exists in Germany and my country ("GPS-assisted beam method area network adjustment". Li Deren, Journal of Surveying and Mapping, Vol. 24, No. 2, 1995 2).

A single remote sensor is placed on a gyro-stabilized platform. When the aircraft is flying, the attitude of the remote sensing platform is kept within a certain angle range (for example: 10). After the remote sensing image is acquired, it can have a good visual effect without processing.

Combination Technology of Single Remote Sensor, GPS Receiver and Attitude Measuring Device

One is the combined technology of imaging remote sensors, GPS receivers, and attitude measurement devices. However, a technical system has not yet been formed;

One is the combination technology of optical machine scanning laser range finder, GPS receiver and attitude measuring device. This type of device is used to obtain DEM. Such as: the Aeronautical Laser Topographic Measurement System (ALTMS) of the Houston Advanced Research Center (HARC); the system of the Jet Propulsion Laboratory (JPL) of the United States and the technical systems of Canada and Germany. But there is no remote sensing imaging technology. See PROGRESS IN GEOREFENCINGAIRBORNE LASER ALTIMETER Presented at the 2th International Airbrne Remote Sensing Conference, San Francisco, California, 24-27Jane 1996.

One is a combined system of microwave remote sensors, GPS receivers, and attitude stabilization equipment in the microwave range. For example: the Interferometric Synthetic Aperture Radar (INSAR) of ERIM disclosed in US Patent No. 4,915,498. It uses the principle of interferometry to find the relative height difference, an image in the microwave band. Data processing of this type of equipment requires a supercomputer, and the processing time after a flight reaches 7 to 15 days.

All the above-mentioned technologies combine the image information, distance information, attitude information, and position information separately and then synthesize them into a series of multi-dimensional remote sensing images. Therefore, the operation is complicated, the cycle is long, and the efficiency is low.

The purpose of the present invention is to solve the problem of quickly producing the accurately matched ground digital elevation model (DEM) and geoscience coded images directly from the information obtained by the aircraft-borne equipment without ground surveying and topographic maps. Greatly shorten the operation process cycle of remote sensing and earth observation technology, and increase the efficiency by more than 100 times.

The technical solution of the present invention is to set the aircraft light-carrying machine scanning imager, the optical machine scanning laser range finder and the attitude measuring device together on a rigid platform, and combine the imager and the main optical path of the laser range finder together to form a Range imaging combined remote sensor. The scanning mirror in the ranging imaging combination remote sensor is used to receive image signals and send and receive laser ranging signals. Then use a synchronous controller (photoelectric encoder) coaxial with the scanning mirror rotation axis to control the range-finding imaging combination remote sensor, attitude measurement device and GPS receiver, so that image data, position data, distance data, and attitude data are provided synchronously and passed through After calculation, interpolation and regression processing, geoscience coded remote sensing images, ground digital elevation models and multi-dimensional remote sensing series images can be directly obtained.

The present invention can be further described according to the embodiments accompanied by accompanying drawings. in:

Fig. 1 is a schematic structural diagram of a remote sensing multi-dimensional information integration device;

Figure 2 is a schematic diagram of the optical path of the ranging imaging combination remote sensor.

The integration device of remote sensing multi-dimensional information among the present invention is to be carried by the optical machine scanning imager 2 of aircraft, optical machine scanning laser range finder 1, attitude measuring device 3, global positioning system (GPS) receiver 4, synchronous controller 9 , data acquisition and recording device 5, and ground or aircraft-borne data processing and imaging and drawing device 6 and other equipment are integrated. Among them, the optical-mechanical scanning imager 2, the optical-mechanical scanning laser range finder 1, the main optical system 8, the scanning mirror 7, the photoelectric encoder 9, etc. constitute a range-finding and imaging combined remote sensor 25 (see FIG. 1 ).

The range-finding and imaging combination remote sensor 25 is used for synchronously providing the remote sensing image data of the ground target point and the distance data between the range-finding and imaging combination remote sensor 25 and the ground target point; the attitude measurement device 3 is a platform compass for providing measurement The attitude data of the combined remote sensor for distance imaging; the global positioning system (GPS) receiver 4 is used to provide the position data of the combined remote sensor for ranging imaging; the synchronization controller 9 is the time synchronization reference of the remote sensing multi-dimensional information integration device, and controls the ranging imaging Combined remote sensor, attitude measuring device, and global positioning system (GPS) receiver synchronously provide image data, distance data, attitude data and position data; data acquisition and recording device 5 is used for image data, distance data, attitude data and position data Collect synchronously and record according to the specified format; the data processing and imaging drawing device 6 is used to process all the data in the data collecting and recording device 5 and draw them into remote sensing multi-dimensional series images. The optical-mechanical scanning imager 2 in the present invention may be a multispectral imager.

The ranging imaging combination remote sensor 25 is composed of the optical-mechanical scanning imager 2 and the optical-mechanical scanning laser rangefinder 1 sharing a set of main optical system 8 (including a scanning mirror 7) (see FIG. 2 ). The synchronization controller 9 is used as a time synchronization reference. The field of view of the ranging imaging combination remote sensor 25 is ±15° or ±22.5°, that is, when the scanning mirror 7 rotates 360° or scans in a swinging manner, only the main optical axis (vertical) faces the ground. Collect data within a predetermined field of view of ±15° or ±22.5°. The mirror surface 19 of the scanning mirror 7 is at 45° to the transmission shaft 15, and the direction of the transmission shaft 15 is consistent with the direction of the aircraft. The scanning mirror 7 scans and rotates around its transmission shaft in a direction perpendicular to the direction of motion of the aircraft. Receive image signals and send and receive laser ranging signals within a predetermined field of view to form a scanning line, which contains a predetermined number of picture elements and a predetermined number of ranging points. The process of imaging and ranging point formation is as follows: the pulsed laser signal sent by the laser 14 turns to the scanning mirror through the turning mirrors 23 and 24, and is reflected by the scanning mirror surface 19 to be emitted to the ground in the direction of the laser 12. The remote sensing image signal 13 of the ground target and the pulsed laser echo signal 11 enter the main optical system synchronously through the reflection of the scanning mirror surface 19, and the laser echo signal is reflected to the laser time-distance digitizer 17 through the transmission-reflection color separation film 18 to obtain the distance Data; the remote sensing image signal reaches the remote sensing image detector 16 through the color separation film 18 to obtain the remote sensing image data of one pixel, and this time synchronization is completed by the synchronous controller 9 .

The synchronous controller 9 can adopt a photoelectric encoder coaxially connected with the transmission shaft of the scanning mirror 7 . Each bit of the photoelectric encoder corresponds to a pixel during imaging. For example, when the photoelectric encoder is 2048 bits and the field of view is ±22.5°, the instantaneous viewing angle of each pixel is 3 milli-curves. The photoelectric encoder sends a code signal to each pixel so that the remote sensing image detector 16 can obtain the image data of the pixel; while sending the code signal to the pixel at intervals of a predetermined number of pixels, a trigger pulse is sent to the laser 14 to generate a ranging pulse Laser signal; send the central pixel time electrical pulse to the attitude measuring device to control the flight attitude data at the central pixel time from the device; the above-mentioned central pixel time electrical pulse is sent to the GPS receiver at the same time, in the GPS receiver A timing mark is generated, and the position data at the mark time is used as the position data of the combined remote sensor.

The attitude measurement device is a platform compass. The attitude data (φ, ω, κ) of the ranging imaging combined remote sensor can be given continuously. The attitude of the ranging imaging combination remote sensor refers to the angle between the main optical axis of the main optical system and the vertical direction of the scanning direction relative to the three coordinate axes of the geographic coordinate system. When the main optical axis is in a strictly vertical state and the scanning direction is consistent with the vertical axis of the geographical coordinates, the readings of φ (pitch angle), ω (roll angle) and κ (yaw angle) of the attitude measurement device should be "0" . The range-finding and imaging combined remote sensor 25 and the attitude measuring device 3 are installed and debugged together on a fixed platform 10 to maintain this rigid coupling relationship.

The data acquisition and recording device uses a formatting circuit to form image data and auxiliary data (time data, line count, laser mode code, GPS event pulse count, image data, distance data, position data, attitude data) in a standard format into a Unified data format output. And recorded on 8mm tape drive or active hard disk.

The data processing and imaging drawing device is a set of computers developed by a software package according to the principle of the present invention for calculation, regression and interpolation processing, and a set of plotters for drawing all the data processed by the computer into remote sensing multi-dimensional series images.

A kind of remote sensing multi-dimensional information integration method of the present invention mainly comprises the following steps: (a) use the optical-mechanical scanning imager in the distance measuring imaging combination remote sensor to receive the image of the ground target point in scanning imaging mode; It is a scanning line; (b) use the synchronous controller to control the optical-mechanical scanning laser rangefinder in the distance-finding and imaging combination remote sensor, and use the scanning mode to scan every predetermined number of pixels in a scanning line, and the imaging moment of this pixel Synchronously send and receive the ranging pulse laser to the ground target point, provide distance data together with the pixel data, and form a point pair of ranging point and imaging point; (c) use the synchronous controller to control the attitude measurement device to provide flight attitude data (d) send electric pulse with synchronous controller, produce timing mark in GPS receiver, output the position data of timing mark moment by GPS receiver; Control GPS receiver with synchronous controller, output central pixel by GPS receiver Time position data; (e) collect and record said all data with data collection and recording device; (f) use data processing and imaging drawing device to process all data and draw into multi-dimensional remote sensing series images.

The optical-mechanical scanning imager 2 receives remote sensing image signals of ground target points by means of uniform-speed scanning imaging to form pixels one by one. Each bit of the photoelectric encoder (such as: 2048 bits) corresponds to a pixel, and each bit of the photoelectric encoder sends out a code signal so that the remote sensing image detector 16 receives the remote sensing signal of the ground target point to become a pixel. Within a predetermined angle range, such as ±22.5° or ±15°, scanning from one corner of the field of view to the other is a scan line, and the photoelectric encoder can sequentially send out 256 (or 512) code signal, the remote sensing image detector 16 can receive 256 (or 512)... and other fixed number of pixels. These pixels are imaged one by one with the rotation of the scanning mirror, and the collection of these pixels is the data volume of one scanning line. Each pixel is numbered according to the imaging sequence, such as: 1~256 (or 1~512), and these numbers are called pixel numbers. The central pixel of a scanning line refers to the pixel whose pixel number is 128 (or 256).

The synchronous controller (photoelectric encoder) controls the laser range finder in the range-finding imaging combination remote sensor to scan every predetermined number of pixels in a scanning line, such as: 4, 8..., and ground target points The pixel imaging time triggers the laser to send and receive the ranging pulse laser to the ground target point synchronously, and obtains the distance data of the ground target point at the same time as obtaining the image data of this pixel, and forms the ranging point and imaging point. point right.

The synchronous controller (photoelectric encoder) transmits electrical pulses to the attitude measuring device synchronously at the imaging moment of the central pixel of each scanning line, which is divided into two routes, one for controlling the attitude measuring device, and the attitude measuring device uses 1/1000 second The data update rate continuously outputs the attitude angle data stream, from which the flight attitude data (φ, ω, κ) at the time of the central pixel is taken out. The electrical pulse sent by the synchronization controller at the moment of the central pixel enters the global positioning system (GPS) receiver in another way. The time mark of the moment when the electrical pulse enters is formed in the GPS receiver, and the GPS receiver continuously outputs the position data stream with a data update rate of 0.1 second or 0.5 second or 1.0 second in time sequence. The time mark formed by the electric pulse of the center pixel is used to interpolate and extract the position data (x, y, z) at the time mark time according to the time.

The instantaneous viewing angle of each pixel in the optomechanical scanning imager 2 is a fixed value, for example, 3 milligulus (or 1 milliarc or 15 milliarc . . . ). The scanning mirror 7 rotates at a constant speed, and the distance-measuring point and imaging point are subtracted from the number of pixels from the center pixel by subtracting the pixel number to obtain the "difference". The angle γ between the ranging direction and the direction of the main optical axis of the combined remote sensor 25 for ranging and imaging can be obtained by multiplying the instantaneous viewing angle by the "difference".

The position data (x, y, z) of the ranging imaging combination remote sensor 25 in flight is given by the GPS receiver; the distance D of the ranging imaging combination remote sensor 25 from the ground target point is scanned by the optical machine laser rangefinder The direction cosine of the ranging direction is composed of the φ, ω, and κ angles given by the attitude measuring device 3 and the included angle γ between the ranging direction and the main optical axis direction of the ranging imaging combination remote sensor 25 . The geographic coordinates (Xi, Yi, Zi) of the ground target point can be marked by the following simple formula: Xi=X+ΔXiYi=Y+ΔYiZi=Z+ΔZi where: ΔXi=f ₁ (φ, ω, κ, γi, Di…)ΔYi=f ₂ (φ,ω,κ,γi,Di…)ΔZi=f ₃ (φ,ω,κ,γi,Di…)

After all such ground target points are obtained, they will cover the entire remote sensing image at approximately equal intervals. According to the geographic coordinates (Xi, Yi, Zi) of these points, the usual fitting interpolation method can be used to obtain Zi arranged in a two-dimensional array (Xi, Yi), that is, the ground digital elevation model (DEM). Similarly, according to the pixel points of these remote sensing images that already have geographical coordinates (Xi, Yi, Zi), according to the usual fitting, interpolation and re-sampling methods, geoscience coded images can be obtained. According to the point pairs of these imaging points and ranging points with geographic coordinates, the DEM (or interpolated contour lines) and the geoscience coded image can be simply combined to form a remote sensing image map. On this basis, remote sensing multi-dimensional series images can be made.

The data collection and recording device 5 collects and records original image data, distance data, position data, and attitude data. The data processing and imaging and drawing device calculates, returns, interpolates, and resamples all the above-mentioned data and draws them into remote sensing multi-dimensional series images.

Another embodiment of the remote sensing multi-dimensional information integration device and method of the present invention is that the optical-mechanical scanning imager 2 and the optical-mechanical scanning laser rangefinder 1 do not share a set of optical systems, but are still separate optical systems belonging to each instrument , but the purpose of the present invention can also be achieved by synchronously collecting image data and distance data through the synchronous controller 9, and such changes all fall within the scope of the present invention.

After the present invention compares with representative remote sensing technology systems such as INSAR, ALTMS, aerial camera, the advantage of the present invention is:

The present invention is an integrated technology that has dozens of bands in the range of visible light and infrared spectrum, can generate DEM, and can be widely used in various special applications; INSAR can generate relative DEM in the microwave range, and has only one band. The remote sensing topic has a narrow range of integrated techniques. ALTMS does not have remote sensing images, but only has the function of generating DEM. Aerial cameras can generate DEM, but the number of bands is too small, and the application range is limited.

Under the same conditions, the present invention should belong to the quasi-real-time system (period of several hours) in the field of geosciences according to the cycle theory of the operation process, and can realize the real-time system in special applications. INSAR takes 7 to 15 days under the same conditions, and ALTMS can only obtain DEM, but cannot be used for remote sensing special applications. Aerial cameras need more than 4 months under the same conditions.

This project has an obvious advantage over other schemes in terms of investment intensity.

Claims (10)

1. A remote sensing multi-dimensional information integration device, characterized in that it includes: A range-finding and imaging combined remote sensor, used to synchronously provide remote sensing image data of ground target points and distance data between the remote sensor and the ground target point; An attitude measurement device, used to provide the attitude data of the range-finding and imaging combination remote sensor; rigidly connected with the range-finding and imaging combination remote sensor; a Global Positioning System (GPS) receiver for providing position data of said ranging imaging combination remote sensor; A synchronous controller, used to control the combined range sensor, attitude measurement device and global positioning system (GPS) receiver to synchronously provide the image data, distance data, attitude data and position data; A data collection and recording device, used for synchronously collecting and recording the image data, distance data, attitude data and position data; A data processing and imaging and drawing device is used to process and draw all the data in the data acquisition and recording device into a series of multi-dimensional remote sensing images. 2. A remote sensing multi-dimensional information integration device as claimed in claim 1, characterized in that: The range-finding and imaging combination remote sensor described herein is jointly composed of an aircraft light-carrying machine scanning imager and an optical-machine scanning laser range finder in a manner of sharing a main optical system. 3. A remote sensing multi-dimensional information integration device as claimed in claim 2, characterized in that: The main optical system mentioned therein includes: Scanning mirror, the mirror surface of the scanning mirror forms an angle of 45° with the ground and its transmission shaft, and scans in a direction perpendicular to the moving direction of the range-finding imaging combination remote sensor, and receives image signals and synchronizes Send and receive laser ranging signals. 4. A remote sensing multi-dimensional information integration device as claimed in claim 3, characterized in that: The scanning mirror scans in a rotating manner, and receives image signals and sends and receives laser ranging signals within the predetermined field of view of the scanning mirror facing the ground, and forms a scanning line. contains a predetermined number of pixels and a predetermined number of ranging points. 5. A remote sensing multi-dimensional information integration device as claimed in claim 3, characterized in that: The scanning mirror scans in a swinging manner, and receives image signals and sends and receives laser ranging signals within the predetermined angle range of the scanning mirror swinging to the ground, and forms a scanning line. contains a predetermined number of pixels and a predetermined number of ranging points. 6. A remote sensing multi-dimensional information integration device as claimed in claim 1, characterized in that: The said attitude measurement device is a platform compass, which is used to continuously provide the flight attitude data of the range-finding imaging combination remote sensor. 7. A remote sensing multi-dimensional information integration device as claimed in claim 1, characterized in that: Wherein said ranging imaging combination remote sensor and said attitude measuring device are installed on a fixed platform together. 8. A remote sensing multi-dimensional information integration device as claimed in any one of claims 4, 5, and 6, characterized in that: The synchronous controller is a photoelectric encoder coaxially connected with the transmission shaft of the scanning mirror, which is used to: send a code signal to each of the picture elements; Send a trigger pulse to the laser rangefinder to generate a ranging pulse laser; send an electrical pulse at the moment of the center pixel to the attitude measurement device to control the flight attitude data at the moment of taking the center pixel from the device; send the moment of the center pixel The electric pulse of the GPS receiver generates the position data at the timing mark time as the position data of the combined remote sensor. 9. A remote sensing multi-dimensional information integration device as claimed in claim 1, characterized in that: Wherein said data processing and imaging drawing device include a computer for calculating, regressing and interpolating said total data, and A plotter for plotting all the remote sensing data processed by computer into a series of multi-dimensional remote sensing images. 10. A remote sensing multi-dimensional information integration device as claimed in any one of claims 4 and 5, characterized in that: Wherein said predetermined number of pixels in the scan line can be 256 or 512; In the scanning line mentioned above, a point pair of a distance measuring point and an imaging point can be formed every 4 pixels or every 8 pixels.

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