Dr. Hongwei Zhang receives NSF CAREER Award to redesign wireless networking
Posted: Friday, May 20, 2011
The World Health Organization (WHO) estimated in a 2009 report that each year more than 1.2 million people die of road traffic injuries, which may become the fifth leading cause of death worldwide by 2030. To combat this trend, the WHO encourages stricter enforcement of more comprehensive traffic laws. At Wayne State University, one researcher is working on another emerging idea: helping vehicles avoid collisions.
To make this idea, known as "active safety," a reality, Hongwei Zhang, Ph.D., assistant professor of computer science in WSU's College of Liberal Arts and Sciences and resident of Troy, Mich., was awarded a $425,000 National Science Foundation Faculty Early Career Development (CAREER) Award to develop a central component of active safety - wireless networks systems.
Wireless network systems are common in cellphones and Wi-Fi. But the wireless networks that make these everyday applications possible are not always reliable, as users whose calls drop daily can attest. And this unreliability can stunt the development of other wireless applications, like wireless vehicular control.
"There's an emerging trend of using wireless networks for mission-critical applications," said Zhang. "In the auto industry, there seems to be an effort to design the next generation of vehicles so that you have zero accidents. But then you may ask, ‘Can we use the wireless technology we have today to support these mission critical applications?' The answer, generally, is no."
One of the issues with today's wireless technology is scheduling transmissions of information between devices, or nodes, in the network. "This issue has been around for decades," said Zhang. "If you have two nodes that want to transmit at the same time, you need to schedule the transmissions so they don't collide with each other." Otherwise, the transmission quality will be reduced. In applications like vehicular or power grid control, this could be dangerous.
Another challenge Zhang hopes to overcome involves sensing and controlling the transmission of information between devices - for example, linking traffic lights with vehicles. If a controller, which controls how the device in the network behaves, is embedded in a traffic light that has turned red, an approaching vehicle would be sensed and the controller would wirelessly signal the vehicle to stop. But in current wireless network technology, the probability of these wireless messages reaching the vehicle would change rapidly over time. "There's a complex pattern and the question is how to deal with this complexity in design," said Zhang.
As Zhang addresses today's limitations in control and scheduling of wireless networks in the Motor City, his focus is predominantly on vehicular control. But, he also sees the potential for wireless systems in health care. "It's something that's being explored heavily and, because we have a strong medical campus, I'd like to look in that direction for future research," Zhang said.