We think of our mobile phones as connecting to mobile networks, but that’s really not the case. When it comes to mobile data, our smartphones are far more reliant on Wi-Fi. Given that’s the case, why are carriers so single-mindedly focused on acquiring new licensed spectrum and building expensive new 3G and 4G networks, when they could implement more Wi-Fi and tap into other sources of unlicensed spectrum? That’s the question a new study is asking.
In a recently released report on unlicensed spectrum, wireless consultant and former Ofcom economist Richard Thanki argues that the wireless industry and its regulators have their priorities all wrong. If the idea is to build ubiquitous networks offering plentiful and cheap data, then carriers and governments should pursue the cheapest and most efficient technologies, which in most cases isn’t cellular infrastructure. That report will be one of the key topics of Center for Internet and Society conference held Wednesday at Stanford University (Our own Stacey Higginbotham will be moderating one of the panels). You can watch the live stream here.
Thanki argues that the ‘spectrum crunch’ is a misnomer. Carriers can support far more capacity if they deploy smaller cells, reusing the spectrum it already has to nth degree. What the mobile industry faces, Thanki says, is an “infrastructure crunch”: It hasn’t built out the density of cells necessary to support the demands for mobile data.
This isn’t a new concept by any means – operators like AT&T, Verizon Wireless and Sprint are now planning their first small cell deployments with an aim of implementing multitechnology heterogeneous networks in the future. But while their plans include Wi-Fi to varying degrees, those operators are still leaning heavily on small cells built over licensed spectrum they own and control, which to Thanki makes absolutely no sense.
“For example a cellular picocell costs from $7,500 to $15,000 whereas a much higher capacity carrier-grade Wi-Fi access point costs around $2,000,” Thanki wrote. “The cost of a Wi-Fi chipset for a consumer device is around $5, whereas 3G cellular chipsets costs around $30.
Thanki said that the insistence on licensed airwaves isn’t a function of efficiency or utility, rather it’s one of control:
Cellular operators are calling for ever more exclusive-use spectrum, in some cases up to 1,000MHz of additional bandwidth. Fulfilling these requests will lead to a substantial concentration in the ownership of the most valuable spectrum, risking both decreased competition and innovation. As part of a balanced approach to meeting the growing demands for data, policy makers should also enable more dynamic spectrum sharing and licence-exempt access across the spectrum. As shown in this report, licence-exemption promotes methods of broadband delivery that are overwhelmingly more efficient in their use of spectrum than their licensed counterparts. In addition, the licence-exempt ecosystem has been notable for creating contestable and competitive markets, characterised by disruptive innovation.
Standards like Wi-Fi, Bluetooth and emerging “super Wi-Fi” technologies can not only support more capacity at a much lower cost, they will be key to connecting rural and underserved areas as well as creating the Internet of Things, in which not just our phones, tablets and laptops are connected but also our homes, cars and appliances. The high costs of mobile data carriage and cellular hardware have already made Wi-Fi a much preferable alternative to mobile broadband, according to Thanki:
Another way of understanding the scale of global Wi-Fi deployments is to compare the aggregate capacity of Wi-Fi networks to global cellular networks. The aggregate capacity of the world’s Wi-Fi networks can be conservatively estimated to be well over 16,500 terabits per second. In comparison, the total capacity of the world’s 3G and 4G radio networks is probably no more 600 terabits per second.
Unlicensed spectrum is already the way the world is heading. Instead of trying to overcome their dependence on Wi-Fi and other unlicensed technologies, Thanki said, carriers and regulators need to embrace them. In his report he doesn’t say that the industry should do away with spectrum ownership completely, but he does recommend that regulators quash their bias for carrier-owned frequencies and strike a balance between licensed and unlicensed. Specifically Thanki recommends that regulators throw open TV white spaces spectrum for unlicensed use, which would trigger the next wave of wireless broadband innovation.