45 research outputs found
Sensing Archaeology in the North: The Use of Non-Destructive Geophysical and Remote Sensing Methods in Archaeology in Scandinavian and North Atlantic Territories
In August 2018, a group of experts working with terrestrial/marine geophysics and remote sensing methods to explore archaeological sites in Denmark, Finland, Norway, Scotland and Sweden gathered together for the first time at the Workshop âSensing Archaeology in The Northâ. The goal was to exchange experiences, discuss challenges, and consider future directions for further developing these methods and strategies for their use in archaeology. After the event, this special journal issue was arranged to publish papers that are based on the workshop presentations, but also to incorporate work that is produced by other researchers in the field. This paper closes the special issue and further aims to provide current state-of-the-art for the methods represented by the workshop. Here, we introduce the aspects that inspired the organisation of the meeting, a summary of the 12 presentations and eight paper contributions, as well as a discussion about the main outcomes of the workshop roundtables, including the production of two searchable databases (online resources and equipment). We conclude with the position that the âNorthâ, together with its unique cultural heritage and thriving research community, is at the forefront of good practice in the application and development of sensing methods in archaeological research and management. However, further method development is required, so we claim the support of funding bodies to back research efforts based on testing/experimental studies to: explore unknown survey environments and identify optimal survey conditions, as well as to monitor the preservation of archaeological remains, especially those that are at risk. It is demonstrated that remote sensing and geophysics not only have an important role in the safeguarding of archaeological sites from development and within prehistorical-historical research, but the methods can be especially useful in recording and monitoring the increased impact of climate change on sites in the North
First Interferometric Trials with the Airborne Digital-Beamforming DBFSAR System
The Microwaves and Radar Institute of the German Aerospace Center (DLR) is known for its consistent work on the field of airborne Synthetic Aperture Radar and its application. Currently, the Institute is developing a new advanced airborne SAR system, the DBFSAR, which is planned to supplement its operational F-SAR system in near future. The development of DBFSAR was triggered by the various evolving digital beamforming (DBF) techniques for future space-borne SAR systems and the need for an airborne experimental platform for preparation of such missions. Additionally, there is a demand for very high resolution SAR imagery, which cannot anymore be fully satisfied with the existing F-SAR system. This paper should give an overview over the current status and performance of the DBFSAR system, including interferometirc results from test flights performed in spring 2017
Deir el-MĂ©dina (2022)
Ce rapport prĂ©sente les travaux rĂ©alisĂ©s en 2022 sur le site de Deir el-MĂ©dina par la mission archĂ©ologique de lâIfao, en partenariat avec plusieurs institutions europĂ©ennes, amĂ©ricaines et Ă©gyptiennes. Le ComitĂ© permanent du MoTA a approuvĂ© le plan dâactions proposĂ©, Ă savoir lâĂ©tude et la restauration de plusieurs monuments, dont la chapelle dâAmennakhte, les tombes TT 8 de KhĂą, TT 216 de Neferhotep, TT 217 dâIpouy, TT 265 dâAmenemipet et le temple ptolĂ©maĂŻque, ainsi que lâĂ©tude du mobilier..
DLR-HR Compact Test Range Facility
A Compact Test Range (CTR) facility shall extend the measurement capabilities at the Microwaves and Radar Institute of the German Aerospace Center (DLR) in Oberpfaffenhofen. Todayâs accuracy requirements in the RF-component characterization are decisive factors for the specification of a new measurement facility. Parts of a Compact Antenna Test Range (CATR) model 8074B, manufactured by March Microwave Systems B.V., have been purchased by the Institute in 2006. On the basis of these components, a compact test range in a new building named âHF-TechLabâ is currently under construction. It is planned to be operational at the end of 2009. An overview of the entire CTR facility is the objective of this paper
Accurate Antenna Characterization for Wideband Synthetic Aperture Radar Processing
The airborne F-SAR sensor, developed and operated by the DLR Microwaves and Radar Institute, provides very high resolution, fully polarimetric synthetic aperture radar (SAR) data in multiple frequency bands that are enhanced by several interferometric imaging modes. The high resolution/high bandwidth regime of operation introduces significant challenges regarding both data calibration and image formation, or focusing. This paper reviews the methods for accurate antenna characterization and the parameter extraction for SAR data processing. The antenna measurements must accurately portray interactions with the surroundings as mounted on the aircraft. The results presented concern the antenna characterization itself and illustrate how the quality of real polarimetric and interferometric SAR data is significantly improved
Horizontally Polarized Antenna Array for an Airborne Ka-PolInSAR System
This paper presents a design of a horizontally polarized antenna array for a new DLR airborne Ka â band polarimetric interferometric synthetic aperture radar system with the maximum gain of 24 dB, low cross - polarization level of - 40 dB and a shaped radiation pattern with low sidelobe level in both azimuth and elevation planes below - 18 dB. It has been designed using the slotted waveguide antenna technology for the center frequency equal to 35.5 GHz. The transverse slots have been cut into the narrow waveguide wall, where the use of iris pairs placed inside enables the radiation. A suitable feeding network consisting of a conventionally H - plane T - junction power divider and a directional waveguide coupler has been also described. Based on theoretical principles, the antenna array as well as the corresponding power splitter have been developed and fabricated while meeting mechanical and electrical system demands. The measurement results of the manufactured prototype have been presented and a good agreement with requirements has been achieved
Cinematic narration in VR - rethinking film conventions for 360 degrees
The rapid development of VR technology in the past three years allowed artists, filmmakers and other media producers to create great experiences in this new medium. But filmmakers are, however, facing big challenges, when it comes to cinematic narration in VR. The old, established rules of filmmaking do not apply for VR films and important techniques of cinematography and editing must be completely rethought. Possibly, a new filmic language will be found. But even though filmmakers eagerly experiment with the new medium already, there exist relatively few scientific studies about the differences between classical filmmaking and filmmaking in 360 and VR. We therefore present this study on cinematic narration in VR. In this we give a comprehensive overview of techniques and concepts that are applied in current VR films and games. We place previous research on narration, film, games and human perception into the context of VR experiences and we deduce consequences for cinematic narration in VR. We base our assumptions on a conducted empirical test with 50 participants and on an additional online survey. In the empirical study, we selected 360-degree videos and showed them to a test-group, while the viewerâs behavior and attention was observed and documented. As a result of this paper, we present guidelines which suggest methods of guiding the viewersâ attention as well as approaches to cinematography, staging and editing in VR
Design of a Horizontally Polarized Slotted Waveguide Antenna Element for Airborne Ka-PolInSAR System
This paper presents the design of a horizontally
polarized slotted waveguide antenna single element with low
cross-pol level, low side lobe level and high gain. This antenna
will be used for the DLR airborne dual polarized Ka-Band
PolInSAR system, which is an extension of the existing airborne
DLR F-SAR sensor [1] and it will be used to investigate
polarimetric interferometric Synthetic Aperture Radar
applications. Based on theoretical analysis an appropriate design
has been developed regarding to the electrical and mechanical
system specifications. The simulation results show a good
fulfillment of the requirements. The measurement results of an 8-
slot prototype of the antenna validate used technology and the
simulation model
Calibration Techniques for Active RCS-Targets
A Dual Reflector Compact Test Range is a versatile environment for measuring antenna radiation patterns as well as the Radar Cross Section (RCS) of radar targets. It is a common practice to achieve adequate accuracy for the antenna measurements by calibrating the test zone with a well-known standard, e.g. a calibrated standard gain horn. This method may not be sufficient for highly accurate measurement of test objects with antennas at offset positions. This paper shows a calibration technique used in the DLR Compact-Test-Range for an active C-band RCS-target with its TX- and RX-antenna at offset positions