Although multiple GNSS constellations such as GPS, GLONASS, and Galileo are now being realized, there are few analysis software for precise surveying that can handle multi-GNSS data including Japanese Quasi Zenith Satellite System (QZSS). The Geospatial Information Authority of Japan (GSI) launched a 4-year project from 2011 to develop and standardize a precise positioning technique that can fully utilize the potential of multi-GNSS data including QZSS for surveys in urban canyons or rapid detection of crustal deformation after large earthquakes. After a brief review of general GNSS software packages, this paper focuses on the status and findings of GSI's multi-GNSS project.
In the past time, “GPS” was the only one available satellite system for the global positioning. During the last decade, “GNSS” has become popular as a general term of satellite based global positioning system which includes GPS and other satellite systems such as GLONASS of Russia. Recently, as deployment plans, such as QZSS (=Quasi-Zenith Satellite System) of Japan, Chinese BeiDou, Galileo of EU, and IRNSS of India, progressed steadily and two or more global positioning systems can be used simultaneously, the multi-GNSS environment became realistic. This report expounds the effect of multi-GNSS and the latest information relating to the multi-GNSS receivers, especially the surveying instruments for which the positioning results of cm order are required.
The real time kinematic positioning (RTK) capability by satellite-based positioning system has been one of the main technology for the information integrated construction including construction survey, machine guidance, machine control and compaction quality control. The Ministry of Land, Infrastructure, Transport and Tourism has promoted the strategic plan for information integrated construction since 2008. With the advent of multi GNSS environment, the availability of RTK has improved under severe conditions such as urban canyon with buildings, wooded valley, and the information integrated construction by RTK has spread for several years. However, there remain some problems ; the accuracy of height by RTK does not satisfy the requirement level of road construction, it is difficult to obtain RTK fix solutions under multipath condition. Quasi Zenith Satellite System (QZSS) and other technical development are expected to contribute to solve the problems.
The forest road network, which has arranged the path through the forested area appropriately, is required for the suitable management of the forest resources to raise the productivity of the forestry. Especially the efficiency of the tree logging work using the forwarder is related to the connectivity of the strip road between the logging area and the main forest network. Therefore, appropriate designing of strip road is one of the important factors for considering the break-even point of the commercial forestry management. Generally, designing of strip road is carried out in following manners. 1) With reference to topographic maps, forest planning maps, aerial photos, etc., domains to be avoided in route locations, such as a steep slope and a danger zone, is classified. 2) Basic alignment of strip road that includes starting point, terminal point, and some major node points is drafted on a map. 3) Basic alignment is actually field surveyed for the final decision. In previous study, the method of designing the forest road network automatically adapting graph theory has been studied. Under consideration of previous study, it is thought possible to examine the way to determine automatically basic alignment of strip road. This research shall be examined on automatically designing of strip road using graph theory and DEM measured by airborne LiDAR. Especially the relation of the alignment of the strip road and the edge direction composed the network of graph theory is considered.
There are some Egyptian pharaonic sites discovered by the utilization of optical and microwave satellite data. Those discoveries suggested us that satellite data can be a powerful tool to detect unknown archaeological sites in the desert of Egypt. On the other hand, there are many Hellenistic archaeological sites at the Nile Delta. As a new application of satellite remote sensing, a wide variety of satellite data such as ALOS/PALSAR, Landsat-7/ETM+, CORONA, and WorldView-2 was used to detect Hellenistic archaeological sites distributed at the Nile delta. As a result of the study, a trace of the ground surface in a rectangular shape considered to be undiscovered Hellenistic archaeological site has been found. It is the first example in the history of archaeology of this area that a previously unknown and potential Hellenistic site of the Nile Delta was discovered by satellite data. This is a preliminary report about the discovery of Site No. 52.
Nakanihon Air Service has developed three types of multiple digital camera system (DCS) including oblique camera and vertical (nadir) camera for aiding airborne lidar. The high image resolution (about 5-10cm) and firm structure leads to good positional matching between lidar point cloud and image using exterior orientation parameter by GNSS-IMU. These images can be used for aiding lidar classification, orthorectified image, morphological analysis, facility monitoring as well as 3D city modeling.