林区GPS控制网的建立及应用

该文通过试验探讨了林区GPS控制网布设的方法和一般原则,研究了基于该网的GPS单点定位、小班边界空间定位和SPOT5、QuickBird等高空间分辨率遥感图像几何精校正地面控制点采集等GPS在林业中应用的主要问题.结果表明,通过以林区GPS控制网差分基准站作为控制点求解高精度的坐标转换参数,手持式GPS单机定位最大综合误差为3.86 m;小班边界平均位移和中心位置绝对位移分别为3.23、3.72 m,小班面积测量精度达到98%以上;所采集的地面控制点综合误差小于0.5 m,完全满足SPOT5、IKONOS及QuickBird等高空间分辨率卫星图像几何精校正的要求,对SPOT5和QuickBird图像进行多项式变换几何精校正,综合误差均小于1个像元.建立林区GPS控制网后,GPS在林区应用的精度和效率大大提高.

Foundation and application of GPS control network in forest districts.

This paper discusses the methods and principles of the foundation of GPS control network in forest districts by the foundation experiment,and studies the main problems of single plot positioning,boundary positioning of sub-compartment,determining the ground control points for geometric correction of high-spatial resolution remote sensing image such as SPOT5 and QuickBird which are based on the GPS control network.The results indicated that,by taking GPS control network as reference station and solving the high-precision coordinate conversion parameter,the largest RMS error of single plot positioning by portable GPS was 3.86 m. The average boundary displacement and absolute displacement of sub-compartment's center were 3.23 and 3.72 m and the accuracy of area measurement was higher than 98%.The RMS error of GCPs was lower than 0.5 m,which completely met the demands of geometric correction of the high-spatial resolution remote sensing image,and all of the RMS errors were smaller than 1 pixel after polynomial transformation geometric correction on SPOT5 and QuickBird images.The accuracy and efficiency of the application of GPS in forest districts were improved effectively after building the GPS control network.