Construction and Accuracy Analysis of a BDS/GPS-Integrated Positioning Algorithm for Forests

The objective of this study was to construct a BeiDou navigation satellite system (BDS)/global positioning (GPS)-integrated algorithm that meets the accuracy requirement forest surveys and analyze its provide theoretical technical support for accurate in forests. Quercus variabilis broad-leaved Jiufeng National Forest Park Sabina Coniferous Dongsheng Bajia farm were selected as area. A Sanding T-23 multi-frequency three-constellation receiver u-blox NEO-M8T multi-constellation receiving module used continuous observation under canopy. Compared with T-23, is much lighter more flexible forest. BDS/GPS-integrated forests constructed by temporally spatially unifying systems using reasonable observed value weighting method. Additionally, also written into RTKLIB software calculate three-dimensional (3D) coordinates point World Geodetic System 1984 (WGS-84) coordinate system. Finally, results compared obtained GPS alone. experimental indicated that, positioning, there 13–27 visible satellites available forests, far than Position Dilution Precision (PDOP) values ranged from 0.5 1.9, lower those positioning. signal noise ratio (SNR) signals both range 10–50 dB-Hz. However, because stronger had stable SNR significantly higher actual accuracies X, Y Z directions algorithm. This suggests can obtain complex environments.