“If you assume they use one carrier for HSPA, the upcoming mobile data traffic growth may be so high that no matter how they evolve to HSPA+ – by implementing 64QAM or MIMO – they may not have enough capacity regardless,” he said at the CommunicAsia Summit Thursday. “In that case they will look at LTE for additional spectrum, to include a TDD option.”
Which raises an even bigger issue for LTE: spectrum fragmentation.
“2.6GHz is the main band for LTE but it raises serious problems with coverage, especially indoors, and it’s not available in all markets,” said Ovum analyst Nathan Burley. “So everyone is looking at digital dividend bands and refarming of 900 MHz and 1800 MHz bands, as well as TDD bands. You’re not going to be able to support all of those in one device, so that will have serious implications for the devices and the LTE ecosystem.”
A related issue is the amount of LTE spectrum cellcos can get, which could limit LTE’s speed advantage over HSPA+, Burley added.
“If you don’t have a 20-MHz channel for LTE, the peak speeds aren’t going to be a big advantage over HSPA+. And there are not a lot of 20-MHz carriers available,” he said.