By Tony Chan
New technologies need to be explored to meet the surging demand for mobile broadband capacity, according to a post on the Cisco blog. “Today, we are facing a big problem,” wrote Steve Wildstrom, a contributing writer on Cisco’s blog and veteran technology writer. “All of the usable spectrum has been allocated, but the explosive growth of smartphones and other wireless devices is creating rapid growth in the demand for bandwidth.”
Finding more spectrum and driving efficiency of mobile networks are potential solutions, but “neither spectral efficiency nor the slow process of freeing and reassigning spectrum seem adequate to meet soaring demand,” Wildstrom noted. He highlighted the recent proposal by the President’s Council of Advisors on Science & Technology to create shared spectrum resources for mobile data, as a starting point in finding alternative solutions.
The PCAST report called for the creation of large spectrum superhighways – unified bands of up to 1000MHz – that can be shared among different applications and service providers. A key component of the proposal was the development of new technologies that allow for applications to share radio resources.
“To do that, one possibility being debated is the use of ‘smart,’ ‘agile,’ or ‘cognitive’ radios that are able to operate on a wide variety of frequencies, using software to sense unused and available channels,” Wildstrom said. “One recent twist on cognitive radios is to have them interact with a secure database that will warn them away from protected radio systems, such as military radar.”
According to Wildstrom, there are already early experiments in “what is likely to become a much broader move toward spectrum sharing as a way to use bandwidth more efficiently.”
Wildstrom acknowledged potential challenges to these new technologies, such as their impact on mobile handset battery life, and paid due to critics of the unproven technologies, including Richard Bennett of the Information Technology and Innovation Foundation, who favours a multi-faceted, market driven approach – rather than backing shared spectrum on its own, which “tilt the scales in favour of one and only one system.”
At the end of the day however, the urgency of the need for new mobile capacity should not discount any new technology, Wildstrom wrote. “The problem is that it is growing increasingly hard to find spectrum that can be easily cleared. The time and effort needed to clear bandwidth means we will need major technological advances in efficiency to close the gap, including potentially, the development of more ubiquitous frequency-sharing technologies.” – www.commsday.com
