Heterogeneous networking is another promising tool in the new standard, Jarich said. It includes mechanisms to make conventional macro cells work better with the smaller cells now being developed to better serve crowded and indoor areas. For example, it could prevent subscribers from being bounced back and forth between large and small cells because of small differences in power between them, he said.
Although all these features may add up to the potential for a true 100Mbps mobile service, it's not clear that carriers could build one or that subscribers even need it. Analyst Phil Marshall of Tolaga Research estimated it would take 50MHz of spectrum to deliver that much speed. To put that in perspective, Verizon Wireless uses just 10MHz each for its upstream and downstream channels today.
With most mobile applications, users couldn't even see any additional speed beyond 20M bps, said Chetan Sharma, principal of Chetan Sharma Consulting. "It's not like the market is crying for 100Mbps," Sharma said.
Most LTE networks aren't even heavily loaded yet, because compatible devices haven't been on the market very long and are still relatively expensive, Marshall said. However, service providers and users may want some of the performance advantages of LTE-Advanced soon, just to preserve or extend the good experience subscribers enjoy now, he said.
"Service providers will rapidly use features of LTE-Advanced that don't dramatically impact their spectrum or network requirements," Marshall said. The result may be just the kind of invisible competence that carriers want. "The speeds will hold better," he said. "You won't see as much variation in performance as you move about the network."