Research On Adjacency Effect Correction Algorithm In Radiant Transfer Of Optical Remote Sensing Information

As the development of the quantitative remote sensing and popular application of remote sensing image data with high spatial resolution, it has become a hot topic to study the theory of remote sensing adjacency effect and explore the method of correcting the adjacency effect. The paper focuses on the adjacency effect in radiant transfer of optical remote sensing information, and analyzes the theory of adjacency effect. What's more, the paper chooses different algorithms corresponding to the two main methods—radiant transfer equation approximate solution and computerized simulation experiment—to make a comprehensive study as for the correction of adjacency effect.For the first kind of method, two algorithms are used:(1) The adjacency effect correction algorithm based on three-dimensional radiation transfer model SHDOM (Spectral Harmonics Discrete Ordinary Method) empirical equation for the nadir-viewing optical remote sensing image. Empirical equation proposed by Shunlin Liang in 2001 based on SHDOM is used to compute the background reflectance. The proportion of energy from target pixel to the whole energy received by the sensor is due to the ratio of relative transmittances.(2) The adjacency effect correction algorithm based on the synchronized measured spectral data. In 2006, Ma put forward this algorithm which makes use of the measured spectral data synchronizing with the remote sensing image to compute the proportion of energy from target pixel to the whole energy received by the sensor. The data sources are Landsat-5 TM image on the July 25th 2005 with synchronized measured spectral data of sand, and ASTER image on the May 23th 2008 with synchronized measured spectral data of grass.The paper also makes a comparative study between the two adjacency effect correction algorithms concerning algorithm principle and correction results.For the second kind of method, whole path backward Monte Carlo algorithm is chose to simulate the photon transfer and get the influence of adjacency pixels in the given atmospheric pattern, aerosol model and ground reflectance.The main contribution and innovation of the paper are:(1) The two algorithms based on the SHDOM empirical equation and based on the synchronized measured spectral data are analyzed deeply in terms of algorithm principle;(2) The whole path backward Monte Carlo algorithm which can simulate the photon transfer is proposed and realized roughly to study the adjacency effect.