Chips that can use a 40MHz band could give device makers the headroom to use better networks as they roll out. But there are other factors that come into play with mobile performance, Ovum analyst Daryl Schoolar said. For one thing, a wireless network with that much bandwidth would need a fat wireline pipe at the base station, probably using fiber, to complete the connection, he said.
"You could see carrier aggregation being used in some areas where the backhaul doesn't support it," Schoolar said. Where that's the case, the maximum speed a subscriber could get for viewing a video or downloading a file would be limited by the wired network. But even so, the additional spectrum could make the user experience more consistent from the center to the edge of a cell's coverage area, he added.
Such performance quotes harken back to lessons consumers learned in the early days of Wi-Fi, said analyst Peter Jarich of Current Analysis.
"Yes, in theory you're going to be able to get 300Mbps with some of this stuff, if you're right next to the base station, and there's no one else using it, and you've got fiber backhaul, and/or there's content right at the base station," Jarich said.
How to estimate real-world performance from such a network? Verizon still quotes the speed of its LTE network at 6Mbps to 12Mbps where it has just 10MHz of spectrum. That would indicate a conservative guess of just 48Mbps with four times as much bandwidth. But the gains from carrier aggregation won't just be linear, Jarich said. Subscribers can get an extra boost because at higher speeds, each user on the network can finish their downloads and uploads sooner and free up the network for the next user, he said.
No matter how fast these networks may be, the game never really ends, according to analyst Phil Marshall of Tolaga Research.
"Consumers can expect operators to market tremendous bandwidth improvements," Marshall said via email. "However, these improvements will be relatively short-lived as subscriber usage network capacity demands increase."
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