Clearwire Makes its LTE Advanced Plans Officialby Brian Klug on August 3, 2011 7:58 PM EST
We've suspected for a long time now that this was inevitable, but Clearwire today announced its official intent to build an "LTE Advanced-ready" network alongside its existing WiMAX network. The move isn't particularly surprising, considering the growing momentum behind the 3GPP camp's competing 4G standard, LTE. Verizon Wireless, AT&T, and LightSquared all have thrown their their might behind LTE in the US, while WiMAX has seen comparatively little momentum beyond an initial growth spurt.
Moreover, Clearwire has been running 20 MHz FDD LTE trials in Phoenix, AZ for some time now. For comparison, Verizon Wireless is running 10 MHz FDD LTE on its 700 MHz band and AT&T will use both 5 MHz and 10 MHz FDD LTE depending on the band (700 MHz and 1700/2100 AWS, respectively).
In today's announcement however, Clearwire indicated that it will use TDD-LTE (Time Division Duplexing, rather than Frequency Division Duplexing, or FDD) on an unnamed "utra-high" amount of spectrum. In all likelihood, that probably means that 20 MHz TDD LTE (3GPP Rel. 8) is in the works initially, followed by a 3GPP Rel.10 "LTE-Advanced" rollout with some number of 20 MHz channels all aggregated (a core LTE-Advanced feature).
The 3GPP camp even has a potential 2x20 + 2x20 TDD carrier aggregation scenario which is prioritized as shown above. This is more than an adequate fit for Clearwire's current spectrum holdings, and could enable the carrier to run more than bandwidths of up to 100 MHz through an aggregation strategy with LTE-Advanced.
One thing is for certain - Clearwire does have a considerable amount of spectrum in its 2.5 GHz band to deploy into, with 194 MHz in the Phoenix market alone as shown above. The upgrade will also have to happen alongside a live WiMAX network which Clearwire will continue running indefinitely in the same 2.5 GHz band.