It’s not easy to give over 1.3 billion people access to the internet especially if that population is spread across, like China. As of June this year, 538 million Chinese people had access to the internet. But that leaves lots of people offline. Researchers at the Beijing University of Posts and Telecommunications are seeking a technology that could revolutionise how internet access is distributed. Existing internet infrastructure typically uses different physical components for different services: cell towers for 3G and 4G, cable or phone lines for home broadband. But a government-backed project in China aims to pack all those connectivity standards together and transmit them through single fibre-optic lines in a technique called radio-over-fibre.
“Repetitive construction is a huge waste of money, time and energy, and the coverage is still limited,” says Kun Xu of the Beijing University of Posts and Telecommunications. “Our aim is to build a broadband access network using just one integrated intelligent system of radio-over-fibre and distributed antennas.”
RoF works by encoding different types of wireless signals into a beam of light and sending them down a fibre-optic cable. At the end of the fibre, those signals are broadcast using a radio antenna, providing 3G and Wi-Fi access simultaneously, for instance. All of the processing that enables internet traffic to turn into radio signals happens at a central station, so RoF is much cheaper to build, run and maintain than typical wireless distribution networks. It also means that new wireless standards such as Long Term Evolution, a common coding standard for 4G wireless, and the latest Wi-Fi protocol, 802.11ac can replace older standards simply by changing equipment at a central point. So far, Chinese authorities have mainly installed RoF in industrial settings such as harbours, hospitals and supermarkets. The aim is to expand coverage into rural areas, along high-speed rail lines, and in the booming construction of new residential and commercial spaces, says Xu.
Jeff Heynen, an analyst at Infonetics Research, which is based in Campbell, California, agrees that RoF is the way forward. “You could carry an entire town’s wireless traffic over a single fibre-optic cable,” he says. Heynen also notes that China’s huge user base means that its demand for RoF will quickly push down the price of the equipment needed to implement it. “The way China goes is the way that the entire worldwide market goes,” he says.
“The future city will not need big, high-power cell towers, expensive coaxial cables, or repetitive network infrastructures for different wireless services,” Xu says. “All the services, wired or wireless, will be supplied by this system and controlled by one central office.”
Via: Beijing University of Posts and Telecommunications
