Deep Space Network information system architecture study

The purpose of this article is to describe an architecture for the Deep Space Network (DSN) information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990s. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies, such as the following: computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control

Cognitive Radio for Emergency Networks

In the scope of the Adaptive Ad-hoc Freeband (AAF) project, an emergency network built on top of Cognitive Radio is proposed to alleviate the spectrum shortage problem which is the major limitation for emergency networks. Cognitive Radio has been proposed as a promising technology to solve todayâ?~B??~D?s spectrum scarcity problem by allowing a secondary user in the non-used parts of the spectrum that aactully are assigned to primary services. Cognitive Radio has to work in different frequency bands and various wireless channels and supports multimedia services. A heterogenous reconfigurable System-on-Chip (SoC) architecture is proposed to enable the evolution from the traditional software defined radio to Cognitive Radio

Coarse-grained reconfigurable array architectures

Coarse-Grained Reconfigurable Array (CGRA) architectures accelerate the same inner loops that benefit from the high ILP support in VLIW architectures. By executing non-loop code on other cores, however, CGRAs can focus on such loops to execute them more efficiently. This chapter discusses the basic principles of CGRAs, and the wide range of design options available to a CGRA designer, covering a large number of existing CGRA designs. The impact of different options on flexibility, performance, and power-efficiency is discussed, as well as the need for compiler support. The ADRES CGRA design template is studied in more detail as a use case to illustrate the need for design space exploration, for compiler support and for the manual fine-tuning of source code

Getting better all the time - The Continued Evolution of the GNSS Software-Defined Radio

Software Defined Radio (SDR) has an infinite number of interpretations depending on the context in which it is designed and used. By way of a starting definition the authors choose to use that of ‘a reconfigurable radio system whose characteristics are partially or fully defined via software or firmware’. In various forms, SDR has permeated a wide range of user groups, from military, business, academia and to the amateur radio enthusiast

Mapping DSP algorithms to a reconfigurable architecture Adaptive Wireless Networking (AWGN)

This report will discuss the Adaptive Wireless Networking project. The vision of the Adaptive Wireless Networking project will be given. The strategy of the project will be the implementation of multiple communication systems in dynamically reconfigurable heterogeneous hardware. An overview of a wireless LAN communication system, namely HiperLAN/2, and a Bluetooth communication system will be given. Possible implementations of these systems in a dynamically reconfigurable architecture are discussed. Suggestions for future activities in the Adaptive Wireless Networking project are also given

Spectrum sensing through software defined radio

Dissertação apresentada para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores, pela Universidade Nova de Lisboa, Faculdade de Ciências e TecnologiaA change in paradigm when it comes to controlling radio transmissions is in course. Tasks usually executed in an exclusive class of hardware systems are increasingly controlled by software systems. A deep change to the software domain is foreseeable, creating a true Software Defined Radio. At the same time this change occurs, the radioelectric spectrum is almost completely licensed. However, the spectrum is rarely used to its full extent over time, enabling its opportunistic use while the licensed devices do not communicate. This is a part of the notion of Cognitive Radio, a new kind of radio capable of using the spectrum in an opportunistic way. These two new paradigms in radio access can be combined to produce a exible and reliable radio, overcoming the issues with radioelectric spectrum scarcity. This dissertation starts an exploration in this area by combining these two paradigms through the use of an Energy Detector implemented in a Universal Software Radio Peripheral device and using the GNURadio suite. The performance of such a system is tested by calculating the Probabilities of Detection and False Alarm in real scenarios and comparing them to the expected theoretical values. A method for defining thresholds for narrowband signals is also tested based on works in Information Theory concepts, i.e.,the Akaike Information Criteria and the Minimum Description Length. The results are tested for a real transmission using two USRP platforms communicating with each other,one acting as the licensed user and the other acting as the secondary, opportunistic user. Finally, we highlight the technological work developed in this dissertation, which may support future research works through the use of the developed scripts, allowing a faster method to test algorithms with different parameterization

State of the art baseband DSP platforms for Software Defined Radio: A survey

Software Defined Radio (SDR) is an innovative approach which is becoming a more and more promising technology for future mobile handsets. Several proposals in the field of embedded systems have been introduced by different universities and industries to support SDR applications. This article presents an overview of current platforms and analyzes the related architectural choices, the current issues in SDR, as well as potential future trends.Peer reviewe