While cat videos, memes and the various other clips and images shared via the Internet provide endless hours of viewing pleasure, they are creating a stress on conventional wireless networks. They produce a huge demand for wireless capacity that cannot be satisfied simply with increases to the existing spectrum.
"According to industry projections that are widely quoted, mobile broadband data demand will grow by a thousandfold between 2010 and 2020," said Upamanyu Madhow, a professor in UC Santa Barbara's Department of Electrical and Computer Engineering. "We are in the middle of this period, and wireless carriers and equipment providers are scrambling to come up with solutions." The demand, he said, is driven by bandwidthhungry multimedia applications, such as streaming services, games and cloud storage, as well as web conferencing and remote desktop services. Should the network become overloaded, Madhow noted, users of these apps would experience the familiar and very frustrating slowdown of service.
However, with the help of $2.4 million in funding from the National Science Foundation, Madhow and fellow UCSB researchers Jim Buckwalter, Mark Rodwell and Heather Zheng, along with Amin Arbabian of Stanford University and Xinyu Zhang of the University of WisconsinMadison, plan to investigate an emerging approach to wireless connectivity. Their research focuses on what is called the "millimeter wave band," an area of the electromagnetic spectrum that operates at a much higher frequency than the radio waves used in conventional wireless communications.
"Frequencies from 30 to 300 GHz are termed 'millimeter wave' because their wavelength is of the order of millimeters," explained Madhow. "Current wireless systems operate in the 1to5 GHz range, with wavelengths of the order of centimeters." Not only would the tiny wavelengths offer additional real estate on the electromagnetic spectrum but their relatively smaller coverage area (called "cells") lends itself to better efficiency.
"The millimeter wave spectrum is a vital component of the next generation of wireless standards, which are being called '5G,' and we at the National Science Foundation have been funding extensive fundamental research in this area over the past three years," said Thyaga Nandagopal, NSF program director for the Networking Technology and Systems program. "This particular collaborative project involving multidisciplinary researchers across three institutions aims to demonstrate the feasibility of a largescale millimeter wave wireless data network that can operate at gigabit speeds." The goal, he added, is to develop the technology by realizing innovative ideas that span circuit design, signal processing, network protocols and communication architecture.
The change in wave scale, however, also means a rethinking of existing wireless infrastructure design principles. For instance, millimeter waves are easily attenuated by relatively small objects, such as human bodies, in addition to the larger objects that are known to interrupt signals in conventional technology, such as buildings.
Photo credit: Matt Perko