I am a regular weekly reader and subscriber to the www.economist.com I could have scanned the entire article, but you can go to the web site and download. This is from February 13th-19th, 2010, page 65. It is simply describing how the current rapid growth in data traffic is overwhelming the current wireless infrastructure. The carriers remember built out their macro infrastructure (cell towers), for voice and never intended for all the data traffic. All the more reason why to expand the network to move the BTS to the in-building environment, hence the growth of the DAS market.
Here are some excerpts from the article.
"In the mid 1990s, cheaper personal computers, faster modems and the birth of the web drove demand. Today it is success of smart phones and devices known as "dongles", which connect laptops to mobile networks. "Cisco, which has a vested interest as the world's biggest maker of network equipment, expects mobile-data traffic to increase 39-fold over the next five years. "Meanwhile operators are scrambling to catch up". AT&T, Americans second biggest mobile operator, is just the most visible example. To secure exclusive rights to the iPhone, it acceded to Apple's demand that the the device come with a simple flat-rate plan. But instead of selling only a few million as expected, AT&T now has an estimated 12-14m iPhones on its network. Its data traffic has grown by 5,000% in the past three years. Things have improved recently, but the network may clog up again if the iPad, Applies newest tablet computer, for which AT&T is providing mobile access, proves a similar success.
Mobile operators are duly beefing up their networks and preparing to roll out LTE, the next generation of wireless technology. But wireless technology is not improving as fast as the kit behind the fixed-line internet services did in the 1990's The number of mobile connections in America has balloned from 2.7m in 1989 to 277m in mid-2009.
Experts predict that to meet the growing demand, operators in developed countries may have to treble the number of base stations (hence the growth of femtocells and BTS/BDA tied to a DAS). The politics of wireless networks is also different. The cheapest way to increase capacity is to add more spectrum or move the network to a lower frequency which allows radio waves to penetrate walls more easily. So operators tend to lobby governments for more and better spectrum before investing in expensive kit. Operators will try to manage traffic in all sorts of ways. One tactic is to offload it to the fixed internet, the iPhone, for instance switches to a Wi-Fi network whenever possible. Another way is to try to get households (could include hospitals), to install what are known as femtocells, wireless base stations for the home. Users would like fixed and mobile internet to be the same, but the huge capacity gap between fiber and radio links is unlikely to ever happen, says Mr.Odlysko. Mr. Metcalfe, meanwhile may have to eat another of his columns. It is my sad duty to inform you, he wrote in 1993, that the resounding flop in wireless mobile computing will be, alas, permanent.