Table of Content

20 March 2014, Volume 43 Issue 3

Previous Issue    Next Issue

Photogrammetry Practice for the First time of LMCCD Camera Imagery

2014, 43(3):  221-225. 

Asbtract ( )   HTML   PDF (1401KB) ( )  

References | Related Articles | Metrics

The LMCCD camera is one of the payload in TH-1 satellite,which is the key step to ensure photogrammetry accuracy without ground control point.The camera parameters of TH-1 is calibrated on-orbit using LMCCD imagery and three-line-array CCD imagery, and the position accuracy are statisticed using different on-orbit calibration results especially the elevation error. The experimental results shows:The adjustment strip system deformation caused by satellite attitude change rate can be resisted in camera on-orbit calibration using LMCCD imagery compared with the single three-line-array CCD imagery.Under condition of the satellite attitude change rate in TH-1,it can be ensure o1 star of TH-1 photogrammetry accuracy without ground control point with camera parameters on-orbit calibration using LMCCD imagery.

Spatiotemporal Data Model for Real-time GIS

2014, 43(3):  226-232. 

Asbtract ( )   HTML   PDF (2368KB) ( )  

Related Articles | Metrics

Abstract: In order to satisfy the requirement of real-time observation data acquisition, storage, analysis and visualization for moving object and sensor, a new type of GIS – Real-time GIS – is needed to develop. A Real-time GIS spatiotemporal data model is proposed for dynamic geographic object and dynamic process simulation according to the characteristics of various geographic features and the requirements of storage management in Real-time GIS, the model integrates some related elements - spatiotemporal process, geo-object, event, event type and state. A new real time GIS based on the spatiotemporal data model has been developed. This paper takes spatiotemporal data real-time access, storage and visualization of four dynamic geographic objects (moving object, situ object, video object and process simulation object) as an example and verifies the feasibility of the model.

Study on Reference Datum of Global Vertical Crustal Motion by SLR Techniques

2014, 43(3):  240-247. 

Asbtract ( )   HTML   PDF (945KB) ( )  

Related Articles | Metrics

It is urgent and necessary to study crustal motion especially in vertical direction along with high frequency happening of Earthquake and geological disasters, while the precondition is to study and establish reference datum of vertical crustal motion. Aiming at the status of disunity of global vertical crustal motion reference datum in domestic and overseas, its essentiality was analyzed to study global uniform reference datum of vertical crustal motion. The project of global vertical crust motion reference datum was put forward and established through SLR vertical velocity field in ITRF2008 frame, whose rationality was demonstrated too. The systematic bias between other velocity field and SLR vertical datum was resolved by using GPS and VLBI observations, and realized the unity of other velocity field and global vertical crustal motion reference datum. Because of abundant geophysical information, expansibility, advancing and relative to the Earth Center, it is recommended that the vertical datum achieved by SLR techniques under the ITRF2008 framework is suitable as a reference datum of the global vertical crustal motion.

Regional Precise Troposphere Delay Modeling Based on Spherical Cap Harmonic Analysis

2014, 43(3):  248-256. 

Asbtract ( )   HTML   PDF (3981KB) ( )  

References | Related Articles | Metrics

The troposphere delay is one of the major error resources for the accuracy of GPS positioning. Empirical models were unable to provide sufficient accuracy for the precise positioning with increasing demand of precision, the Continuously Operating Reference Stations (CORS) built around the world shed lights on constructing more precise tropospheric delay model. Based on the analysis of drawbacks of common real-time regional tropospheric delay models, a new regional real-time troposphere model based on spherical cap harmonic analysis (SCHA) is proposed in this paper. Comparative analysis between SCHA model and four-parameter model show that internally coincident precision of the new model is obvious improved (RMS < 5 mm); its externally coincident precision increases about 50% (RMS < 1 cm). SCHA model could describe special variations of troposphere more reasonably and is adequate to regional real-time troposphere delay modeling for large areas.

Direct solution of SLR and VLBI antenna rotation center

2014, 43(3):  257-262. 

Asbtract ( )   HTML   PDF (2848KB) ( )  

Related Articles | Metrics

To accurately determine the rotation center of SLR (Satellite Laser Ranging) and VLBI (Very Long Baseline Interferometry) is a key problem in surveying co-located tie vector. This paper develops an approach of directly solving the collocated tie vector by using two kinds of constraints between SLR and VLBI’s antenna rotation center and observation marks. The first constraint is that the mark forms a planar circle when it rotates along with its rotation axis, which can be modeled as the intersection of a plane and a sphere. The second constraint is that the rotation center lies in the same plumb line with the rotation center of vertical axis, and in the same plane with the rotation center of horizontal axis. The corresponding condition equations are established according to the two kinds of constraints. The tie vector and its covariance matrix are directly resolved by using the observations of the mark points. The space differences baseline are solved based on the direct approach using measured data of seven GNSS (Global Navigation Satellite System) and SLR or VLBI co-location. The results show that the difference is better than 1mm compared with two step solutions.

APPLICATION OF ADAPTIVE SMOOTHING FUNCTION FILTERING BASEED ON GRADIENT IN InSAR IMAGE

2014, 43(3):  263-267. 

Asbtract ( )   HTML   PDF (4412KB) ( )  

Related Articles | Metrics

A new filtering algorithm smoothing function based on gradient was proposed. Based on gradient, noise points are identified. This algorithm is based on the spatial curved surface fitting, and then the surface is processed through smoothing function. The good pixels are unsmooth. The results of experiment, using the data which come from ALOS data of Beijing, show that the smoothing function filer has effectiveness and feasibility. The RMS (Root mean square error), PSNR (Peak signal-to-noise ratio), EPI(Edge preserve index) and PSD (Phase standard deviation) suggest that the algorithm can reduce the speckle noise and keep the edge information.

Automated Multispectral Remote Sensing Image Registration Based on Local Self-similarity

2014, 43(3):  268-275. 

Asbtract ( )   HTML   PDF (3743KB) ( )  

Related Articles | Metrics

This paper proposes an automated registration method for multispectral remote sensing images to address the significant non-linear intensity differences among such images. The proposed method first introduces the local self-similarity (LSS) feature, and builds the feature descriptors capturing the internal geometric layouts and shape properties of images in the log-polar coordinate. Then, a shape similarity measure is defined by combining LSS and normalized correlation coefficient, followed by the template-matching scheme to achieve image registration. Experimental results show that the proposed method is robust to non-linear intensity differences among images and achieves reliable registration accuracy，and obtains a higher correct matching rate in consideration of the computational efficiency compared with state-of-art registration methods.

A Super-resolution Model and Algorithm of Remote Sensing Image based on Sparse Representation

2014, 43(3):  276-283. 

Asbtract ( )   HTML   PDF (1796KB) ( )  

Related Articles | Metrics

In order to enhance the spatial resolution of a single remote sensing image, a super-resolution reconstruction method based on sparse representation is presented in this work. First, a pair of dictionaries for low- and high- resolution image patches are learned using the majorization minimization method. The method substitutes the original objective function with a surrogate function that is updated in each optimization step, and can guarantee to find local minima in each optimization step. Second, given a low-resolution remote sensing image, the high-resolution image is reconstructed based on the pair of dictionaries.Our experiments show that the state-of-the-art results have been achieved compared to conventional interpolation methods in terms of both PSNR,SSIM and visual perception.The results demonstrate that our algorithm can provide useful high-frequency details for a single low-resolution remote sensing image in super-resolution reconstruction, and therefore the proposed method is universal.

A precise method to measure the on-orbit point spread function of remote sensors

2014, 43(3):  284-289. 

Asbtract ( )   HTML   PDF (2188KB) ( )  

References | Related Articles | Metrics

A new approach to measure the on-orbit point spread function of remote cameras is proposed here. Based on the classical step-edge method, we made a profound analysis about the influence of the tilted angle, size, interpolation, contrast, pixel saturation and noise of the step-edge image. The conditional step-edge image is first detected and then processed to weaken the impact of sampling phase in order to improve the precision of the measurement. The experiment on real remote sensing panchromatic data demonstrates the effectivity and credibility of the new method. Furthermore, the degraded image is restored using the measured point spread function; the quality of the image is significantly improved.

An Automatic Registration Method for Multi-Temporal Remote Sensing Images Using Land Cover Patches

2014, 43(3):  290-297. 

Asbtract ( )   HTML   PDF (2829KB) ( )  

References | Related Articles | Metrics

An automatic registration method for multi-temporal remote sensing images using stable land cover patches was proposed in this paper, taking full advantage of multi-spectral features as well as stable and widespread land cover patches in remote sensing images. Rural regions, where significant land cover changes happened within-and between-year, were chosen as study area, and multi-temporal remote sensing images from same or different sensors were used. Experimental results showed the effectiveness and adaptability on extraction of stable land cover patches of this method, and registration accuracies of 0.57 and 0.65 pixels were achieved.

A Registration Approach Based for Airborne Repeat Pass InSAR

2014, 43(3):  298-305. 

Asbtract ( )   HTML   PDF (2609KB) ( )  

Related Articles | Metrics

As one of the basilica steps in InSAR data processing, the accuracy of registration affects the quality of subsequent processing. Because of different flight attitudes, there is large relative deformation between images obtain by airborne SAR system from different flight courses. Conventional methods cannot deal with the entire images. In this paper, the robustness of the SIFT matching algorithm and high precision of analytic search registration approach are combined, excluding the mismatch using the relationship between the flight path and statistical analysis of offset between images, and a method is proposed for registration of airborne repeat pass InSAR, which effectively solves the problem in registration of airborne repeat pass InSAR. First, SIFT matching algorithm to extract matching points, and then eliminate false matching points using the relationship between flight courses and statistical analysis of the offset of matching points, to complete the rough registration, and finally use analytic search method to complete the fine resolution. P-band airborne repeat pass InSAR data obtained by CASMSAR are processed and good results are achieved.

Research and Application of Two-peak Changing Law of Electronic Map Load

2014, 43(3):  306-303. 

Asbtract ( )   HTML   PDF (4163KB) ( )  

References | Related Articles | Metrics

Electronic map load is one of the most important factors that influence the clarity, smooth and gradation of the multi-scale display; and it is also an important indicator in multi-scale representation modeling. All of these make the research of electronic map load more significance. This article analyzed differences of the map load variation between paper map and electronic map; using RGB values-based approach to obtain a large number of electronic map data; explored two-peak changing law of electronic map load by making further research; discussed the curve shape and influencing factor of two-peak changing law of electronic map load. In the end, it established a more scientific and practical electronic map multi-scale model, and this achieved a preferable experiment results.

Urban Hotspot Detection and Commercial Area Analysis based on Check-in Data Using Exploratory Spatial Data Analysis

2014, 43(3):  314-321. 

Asbtract ( )   HTML   PDF (2921KB) ( )  

References | Related Articles | Metrics

Crowd sourcing geographic data is an open source geographic data which is contributed by lots of non-professionals and provided to the public. As a kind of crowd sourcing geographic data, check-in data contains multitudes of social attribute data and reflects people’s activities of daily living objectively and actually. The paper proposes a method of urban commercial area mining and analysis based on check-in data: Firstly, the paper studies the spatio-temporal distribution characteristics of check-in data and designs a spatio-temporal database model for check-in data; Secondly, the paper proposes an exploratory spatial data analysis method of check-in data and achieves commercial hotspot detection based on check-in data by spatial clustering analysis of check-in data; Finally, an experiment of urban commercial mining and analysis with the check-in data obtained from Jiepang by the deadline of September 30, 2011 in Wuhan is designed and implemented. The result shows that the urban commercial area distribution of Wuhan based on check-in data has a high correlation with urban planning and can be used for regional planning of urban society development.

Full Tensor Geomagnetic Gradient Reference Map Building and Its Integrated Navigation Algorithm

2014, 43(3):  322-328. 

Asbtract ( )   HTML   PDF (2838KB) ( )  

Related Articles | Metrics

In order to realize the INS/geomagnetic gradient added integrated navigation using geomagnetic gradient, the paper presented a new theorem of phase-shifted cosine transform time-differentiation. Meanwhile a formula for calculating the full tensor magnetic gradient components was deduced. The high accuracy reference map for geomagnetic gradient added navigation has been realized. The improved particle filter algorithm has been incorporated into the integrated navigation system to overcome the accumulated position error with time. Through the simulation, the results verify the effectiveness and robustness of the proposed method. The geomagnetic gradient added integrated navigation system has better estimation precision with approximately 100 m