This high-risk high-reward project is concerned with the urgent need to design and deploy wireless networks that withstand time in hazardous, radioactive environments, such as a nuclear plant disaster. A hazardous, radioactive environment is particularly insidious because sensing and communication devices deployed in the environment are exposed to radioactive emissions - hence, their extraction for recharging/repair is challenging, and their efficient operation may be seriously impacted if hardware not hardened for radiation is used, and because in this physical space non-cooperating wireless communication technologies, e.g., wireless mesh and sensor networks, need to coexist. This EAGER project explores a pathway and solutions towards achieving a significant increase in the operation time of coexisting wireless mesh and sensor networks deployed in a hazardous environment. The intellectual merit lies in a radical new approach (anchored in a new and solid Markov chain-based theoretical foundation, for achievable throughput, delay and energy efficiency) for a crosslayer design of ultra-energy efficient wireless communication protocols that employ duty cycling and network coding. The broader societal impact of the proposed research goes beyond the traditional impact of scientific research, literally affecting life and death. Results of the proposed research will be integrated with RESPOND-R, an NSF-funded instrument for emergency response research, deployable in hazardous environments throughout the US, where it could possibly save lives. This project will also offer research opportunities to graduate and undergraduate students and to underrepresented groups.
This high-risk high-reward project was concerned with the urgent need to design and deploy wireless networks that withstand time in hazardous, radioactive environments, such as a nuclear plant disaster. A hazardous, radioactive environment is particularly insidious because sensing and communication devices deployed in the environment are exposed to radioactive emissions - hence, their extraction for recharging/repair is challenging, and their efficient operation may be seriously impacted if hardware not hardened for radiation is used, and because in this physical space non-cooperating wireless communication technologies, e.g., wireless mesh and sensor networks, need to coexist. This EAGER project explored several pathways and solutions towards achieving a significant increase in the operation time of coexisting wireless mesh and sensor networks deployed in a hazardous environment. The intellectual merit consisted in a radical new approach (anchored in a new and solid Markov chain-based theoretical foundation, for achievable throughput, delay and energy efficiency) for a crosslayer design of ultra-energy efficient wireless communication protocols that employ duty cycling and network coding. To meet the objectives of the proposed EAGER research the major activities we performed were: a) we performed fundamental research in wireless networking; b) trained PhD students for cutting edge research and disaster responders at the Texas Task Force 1 - the entity that responds to disasters nationwide and in the State of Texas; and c) we have disseminated our results through research articles, course materials, and released open source code. To meet the objectives of the proposed EAGER research, we conducted research in severak distinct, but inter-related areas: a) multiple access control and routing protocols for aggressive energey efficiency in Disaster Response Scenarios; b) wireless coexistence modeling and analysis for, ultimately, aggressive energy efficiency in Disaster Response, where coexistence of WiFi and ZigBee networks is challenging; and c) applications and middleware for Disaster Response situations, with the goal to save energy, but to also provide other QoS guarantees to users. Our results in the aforementioned research areas are as follows: a) we developed algorithms and protocols, that provably, achieve near optimal performance. We demonstrated the effectiveness of our solutions through simulations and real system implementations.; b) we derived, for the first time, closed form solutions for throughput and delay in WiFi and ZigBee coexisting networks. Using our proposed models, our research developed a novel approach for joint protocol tuning, that satisfies delay constraints of ZigBee (while maximizing WiFi throughput). Additionally, and important for the research community, we extended the ns-3 framework with coexistence simulation capabilities, verified on real hardware, that validate our proposed model and protocol tuning methods; c) we developed portions for the first design and implementation of a complex system (i.e., sensing, networking, data management) for emergency response that addresses US&R responder requirements and is evaluated in a realistic environment, utilizing over 1500 man-hours worth of deployment experiences and data.
