Dynamic link budget simulation

A new simulator named DLBS (Dynamic Link Budget Simulator) was written to simulate the time-varying communication link between a vehicle that re-enters the atmosphere from the outer space, and a ground station. During the vehicle descent trajectory, communications blackouts typically occur due to the effects of plasma that forms around the vehicle. A companion simulator, AIPT (Antenna In Plasma Tool), evaluates the electric field at the input of the ground station antenna, taking into consideration the vehicle structure, its antenna, the characteristics of plasma at some specified points along the vehicle trajectory, and the obtained values are stored in a file. DLBS processes the data read from the AIPT output file and evaluates the corresponding channel transfer functions. DLBS then allows to simulate the typical telemetry and telecommand links, using both CCSDS standardised and some non standard channel encoding schemes and modulations. For each generated frame, DLBS uses a channel transfer function obtained by adequately interpolating the two nearest transfer functions evaluated in the initial phase. DLBS includes realistic frame, frequency, phase and bit synchronisation, so that synchronisation errors are also included as source of performance degradation, and measures both the average bit and frame error rates, and the bit error rate at frame level, so that it is possible to appreciate the dynamic system behaviour. The paper will show the results obtained for a case stud

The Road to the Antiquities Act and Basic Preservation Policies It Established

3 pages

Dynamic link budget simulation

A new simulator named DLBS (Dynamic Link Budget Simulator) was written to simulate the time-varying communication link between a vehicle that re-enters the atmosphere from the outer space, and a ground station. During the vehicle descent trajectory, communications blackouts typically occur due to the effects of plasma that forms around the vehicle. A companion simulator, AIPT (Antenna In Plasma Tool), evaluates the electric field at the input of the ground station antenna, taking into consideration the vehicle structure, its antenna, the characteristics of plasma at some specified points along the vehicle trajectory, and the obtained values are stored in a file. DLBS processes the data read from the AIPT output file and evaluates the corresponding channel transfer functions. DLBS then allows to simulate the typical telemetry and telecommand links, using both CCSDS standardised and some non standard channel encoding schemes and modulations. For each generated frame, DLBS uses a channel transfer function obtained by adequately interpolating the two nearest transfer functions evaluated in the initial phase. DLBS includes realistic frame, frequency, phase and bit synchronisation, so that synchronisation errors are also included as source of performance degradation, and measures both the average bit and frame error rates, and the bit error rate at frame level, so that it is possible to appreciate the dynamic system behaviour. The paper will show the results obtained for a case study

Technical Brief 17: Developing an Archeological Site Conservation Database

Though the conservation and long-term management of archeological sites is not generally accepted wisdom, it wasn’t always so. A traditional bias toward excavation and the keeping of only basic site data has had effects that longer on today. Historically, and to the detriment of long-term site care, information has been collected with only fundamental concerns such as location and interpretation in mind. Excavation was favored over in-place conservation, under the assumption that the latter was too complicated and expensive. But the true cost of the excavation if often more than anticipated, and often grows as the curation of objects is projected into the future. Toward Proactive Management Archeological Site Management Dat

Technical Brief 17: Developing an Archeological Site Conservation Database

Though the conservation and long-term management of archeological sites is not generally accepted wisdom, it wasn’t always so. A traditional bias toward excavation and the keeping of only basic site data has had effects that longer on today. Historically, and to the detriment of long-term site care, information has been collected with only fundamental concerns such as location and interpretation in mind. Excavation was favored over in-place conservation, under the assumption that the latter was too complicated and expensive. But the true cost of the excavation if often more than anticipated, and often grows as the curation of objects is projected into the future. Toward Proactive Management Archeological Site Management Dat

Sites and Monuments: National Archaeological Records, edited by Carsten U. Larsen, The National Museum of Denmark. DKC, 1992

This volume includes most of the presentations made at the first National Records Conference, hosted by the National Museum of Denmark during May 1991, in Copenhagen. The three day meeting was attended by representatives of 60 countries. This collection brings together revised versions of 19 of the papers presented at the conference. With the exception of two presentations about national records in Poland and one from the United States, all the papers describe systems or initiatives in Western European countries, including six from the United Kingdom

Hope in dirt: report of the Fort Apache Workshop on Forensic Sedimentology Applications to Cultural Property Crime, 15—19 October 2018

A 2018 workshop on the White Mountain Apache Tribe lands in Arizona examined ways to enhance investigations into cultural property crime (CPC) through applications of rapidly evolving methods from archaeological science. CPC (also looting, graverobbing) refers to unauthorized damage, removal, or trafficking in materials possessing blends of communal, aesthetic, and scientific values. The Fort Apache workshop integrated four generally partitioned domains of CPC expertise: (1) theories of perpetrators’ motivations and methods; (2) recommended practice in sustaining public and community opposition to CPC; (3) tactics and strategies for documenting, investigating, and prosecuting CPC; and (4) forensic sedimentology—uses of biophysical sciences to link sediments from implicated persons and objects to crime scenes. Forensic sedimentology served as the touchstone for dialogues among experts in criminology, archaeological sciences, law enforcement, and heritage stewardship. Field visits to CPC crime scenes and workshop deliberations identified pathways toward integrating CPC theory and practice with forensic sedimentology’s potent battery of analytic methods

Using Ethnographic Methods to Articulate Community-Based Conceptions of Cultural Heritage Management

How can ethnographic methods help communities articulate and enact their own conceptions of heritage management? This and related questions are being explored through an international research project, ‘Intellectual Property Issues in Cultural Heritage’. The project includes up to twenty community- based initiatives that incorporate community-based participatory research and ethnographic methods to explore emerging intellectual property-related issues in archaeological contexts; the means by which they are being addressed or resolved; and the broader implications of these issues and concerns. We discuss three examples that use ethnography to (a) articulate local or customary laws and principles of archaeological heritage management among a First Nations group in British Columbia; (b) assemble knowledge related to land/sea use and cultural practices of the Moriori people of Rekohu (Chatham Islands) for their use in future land and heritage manage- ment policies; and (c) aid a tribal cultural centre in Michigan in crafting co-management strategies to protect spiritual traditions associated with a rock art site on state property. Such situations call for participatory methods that place control over the design, process, products, and interpretation of ‘archaeology’ in the hands of cultural descendants. We hope that these examples of community-based conceptions of archaeological heritage management, facilitated through ethnographic methods and participatory approaches, will increase awareness of the value of these and other alternative approaches and the need to share them widely

Participatory Augering: A methodology for challenging perceptions of archaeology and landscape change

Public engagement is a significant feature of twenty-first-century archaeological practice. While more diverse audiences are connecting with the discipline in a multitude of ways, public perceptions of archaeology are still marred by stereotypes. Community excavations of ‘sites’ to discover ‘treasures’ which tell us about the ‘past’ overshadow other forms of public research output and hinder the potential of the discipline to contribute to contemporary society more widely. This paper proposes participatory augering as an active public engagement method that challenges assumptions about the nature of archaeological practice by focusing on interpretation at a landscape-scale. Through exploration of recent participatory augering research by the REFIT Project and Environmental Archaeologist Mike Allen, this paper demonstrates how the public can contribute to active archaeological research by exploring narratives of landscape change. Evaluation of the existing case studies reflects the potential of the approach to engage audiences with new archaeological methods and narratives which have the potential to transform perceptions of the discipline and, through knowledge exchange, drive community-led contributions to contemporary landscape management