Altay Aksulu Schulich School of Business, York University aaksulu@schulich.yorku.ca

/pdf/a-comprehensive-review-and-synthesis-of-open-source-research-5fkclzdy77.pdf

A Comprehensive Review and Synthesis of Open Source Research

New techniques in cross-layer wireless networks are building demand for ubiquitous channel sounding, that is, the capability to measure channel impulse response (CIR) with any standard wireless network and node. Towards that goal, we present a software-defined IEEE 802.11b receiver and CIR measurement system with little additional computational complexity compared to 802.11b reception alone. The system implementation, using the universal software radio peripheral (USRP) and GNU Radio, is described and compared to previous work. We validate the CIR measurement system and present the results of a measurement campaign which measures millions of CIRs between WiFi access points and a mobile receiver in urban and suburban areas.

/pdf/channel-sounding-for-the-masses-low-complexity-gnu-802-11b-3hp8fjkai2.pdf

Channel Sounding for the Masses: Low Complexity GNU 802.11b Channel Impulse Response Estimation

We present the details of a portable, powerful, and flexible software-defined radio development platform called the Kansas University Agile Radio (KUAR). The primary purpose of the KUAR is to enable advanced research in the areas of wireless radio networks, dynamic spectrum access, and cognitive radios. We describe the KUAR hardware implementation and software architecture and present example application of the KUAR to modulation, spectrum measurement, channel estimation, and rapid configuration and adaptation. We outline research directions enabled by the KUAR

COGNITIVE RADIOS FOR DYNAMIC SPECTRUM ACCESS - An Agile Radio for Wireless Innovation

Networked Cyber-Physical Systems (NCPS) present many challenges that are not suitably addressed by existing distributed computing paradigms. They must be reactive and maintain an overall situation awareness that emerges from partial distributed knowledge. They must achieve system goals through local, asynchronous actions, using (distributed) control loops through which the environment provides essential feedback. Typical NCPS are open, dynamic, and heterogeneous in many dimensions, and often need to be rapidly instantiated and deployed for a given mission. To address these challenges, we pursue a declarative approach to provide an abstraction from the high complexity of NCPS and avoid error-prone and time-consuming low-level programming. A longer-term goal is to develop a distributed computational and logical foundation that supports a wide spectrum of system operation between autonomy and cooperation to adapt to resource constraints, in particular to limitations of computational, energy, and networking resources. Here, we present first steps toward a logical framework for NCPS that combines distributed reasoning and asynchronous control in space and time. The logical framework is based on partially ordered knowledge sharing, a distributed computing paradigm for loosely coupled systems that does not require continuous network connectivity. We illustrate our approach with a simulation prototype of our logical framework in the context of networked mobile robot teams that operate in an abstract instrumented cyber-physical space with sensors.

/pdf/toward-distributed-declarative-control-of-networked-cyber-22ydti7erg.pdf

Toward distributed declarative control of networked cyber-physical systems

Physical layer security mechanisms have drawn increasing research interest recently along with the development of software defined radio (SDR) techniques. This paper proposes a physical layer watermarking technique named Watermarked Direct Sequence Spread Spectrum (DSSS) or WDSSS technique, which embeds authentication information into pseudonoise (PN) sequences of a DSSS system. The design and implementation of the WDSSS prototype system on the GNU Radio/USRP SDR platform are discussed, as well as two embedding methods, the maximized minimum distance method and the sub-sequence method. Theoretical analysis and experimental results on the WDSSS prototype system are presented to evaluate the performances of both the content signal and the watermark signal. Results show that, for the 11-chip PN sequence, the impact of artificial chip alteration to the content signal is quantitatively predictable, with 2 dB extra signal-to-noise ratio (SNR) required to maintain an acceptable packet error rate for one additional flipped chip. The properties of embedding methods are also analyzed and compared.

/pdf/physical-layer-watermarking-of-direct-sequence-spread-28v164fvvn.pdf

Physical Layer Watermarking of Direct Sequence Spread Spectrum Signals

The ADROIT project is building an open-source software-defined data radio, intended to be controlled by cognitive applications. The goal is to create a system that enables teams of radios, where each radio both has its own cognitive controls and the ability to collaborate with other radios, to create cognitive radio teams. The desire to create cognitive radio teams, and the goal of having an open-source system, requires a rich and carefully architected system that provides great flexibility (enabling cognitive applications to change the radio's behavior) and also has a clear structure (both so that others may add or enhance the software, and also so that the system can be clearly modeled for cognitive applications). What follows is a summary of the ADROIT system and the key architectural features intended to enable cognitive radio teams.

/pdf/adaptive-dynamic-radio-open-source-intelligent-team-adroit-5afzet8v1m.pdf

Carl Livadas

Papers

Adaptive Dynamic Radio Open-source Intelligent Team (ADROIT): Cognitively-controlled Collaboration among SDR Nodes

Enabling open-source cognitively-controlled collaboration among software-defined radio nodes