Investigations into radio communications during 9/11 rescue efforts revealed that many first responders experienced difficulties communicating because of oversaturation of radio channels, lack of interoperability between the radio systems of responding agencies, and damaged or failed network infrastructure. Interoperability of radio systems and intelligent spectrum access could be vital in large-scale emergency situations, enabling the multiple responding agencies to communicate and coordinate their efforts.
The Wireless Innovation Forum recently challenged teams from universities around the nation to build a dynamic router or spectrum sensor that can be used by public safety agencies. Stevens Institute of Technology doctoral candidates Vidya Sagar and Adonis Hong, advised by Dr. R. Chandramouli and Dr. K.P. Subbalakshmi of the Department of Electrical and Computer Engineering, were awarded second place in the Software-Defined Radio challenge at the 2012 Wireless Innovation Forum held at Virginia Tech. The Stevens project was titled “SpiderRadio: A Programmable Multi-radio Dynamic Spectrum Access Mobile Router.”
“Radio communications have proven to be crucial in crisis response situations, and the development of more versatile and sophisticated radio technologies will greatly enhance their usefulness,” says Dr. Michael Bruno, Dean of the Charles V. Schaefer, Jr. School of Engineering and Science. “We are tremendously proud of Vidya and Adonis for distinguishing themselves in what is a national research imperative.”
SpiderRadio is a low-cost, software-driven cognitive radio prototype that scans the radio spectrum, detects users or interference on a channel, and switches dynamically to the best available communications channel. “A poor connection on a leisurely phone call is a minor nuisance, but for public safety officials and the citizens they are protecting, even a short-term drop in quality can be devastating,” says Dr. Chandramouli. SpiderRadio therefore uses two levels of 'sensing' mechanisms to predict a potential outage of network connectivity and 'switch' applications from one network to another in order to provide robust and secure network connectivity. Furthermore, SpiderRadio achieves interoperability and optimal performance at a cost that could potentially allow for public safety agencies to adopt the technology.
Vidya Sagar is pursuing a PhD in Computer Engineering at Stevens. He recieved the Stevens I&E fellowship in his first semester. Prior to Stevens, he studied in India, recieving a B.S. in Electronics and Communication Engineering and a master's degree in Information Technology. As a master's student, his research resulted in several publications and patent applications in the areas of communication systems and network research.
Kai Hong is also pursuing a PhD in computer engineering at Stevens. He received the Stevens I&E fellowship in his first two years at Stevens. Prior to Stevens, he studied in China and received a B.S. in automatic control and an M.S. in image processing. His graduate research in China included work on image recognition, ultrasonic guided wave testing of pressure vessels, and a distributed steel mill control system.
SpiderRadio can also benefit the general public use because of its ability to connect to multiple wireless technologies that include Wifi and 3G/4G. It intelligently combines all these different technologies so that user applications (such as a browser or instant messaging application) can operate seamlessly even when connectivity falters. As of now SpiderRadio is prototyped as mobile router but it can be easily be implemented as an application for smart phones and portable devices.
At the Wireless Innovation Forum, undergraduate and graduate students or teams of students, advised by a faculty member, proposed and solved problems related to software-defined radio. Topic areas included dynamic spectrum access, public safety applications, and interoperability/bridging. The projects were evaluated by wireless communications industry professionals based on the importance and timeliness of the problem addressed, performance of solution, flexibility, degree of automation/adaptive capability, ease of use, size, weight, power, and cost effectiveness.
The Stevens cognitive radio group is a world-recognized leader in the field. Dr. Subbalakshmi is the Vice-Chair of the IEEE Technical Committee on Cognitive Networks, as well as being an invited keynote speaker, panel speaker, or tutorial speaker at numerous major international conferences on cognitive and software defined radio. Dr. Chandramouli was invited to a White House roundtable to give input on cognitive radio for public safety, and he is the founding editor of IEEE Journal on Selected Areas in Communications—Cognitive Radio Series .
Dr. Chandramouli and Dr. Subbalakshmi’s research on cognitive radio is funded by two NSF grants, as well as a grant from National Institute of Justice. Along with their doctoral candidates and undergraduate researchers, they have been studying fundamental research problems as well as developing and refining their SpiderRadio prototype.
Established in 1996, The Wireless Innovation Forum (SDR Forum Version 2.0) is a non-profit mutual benefit corporation dedicated to driving technology innovation in commercial, civil, and defense communications worldwide. Members bring a broad base of experience in Software Defined Radio (SDR), Cognitive Radio(CR) and Dynamic Spectrum Access (DSA) technologies in diverse markets and at all levels of the wireless value chain to address emerging wireless communications requirements.