Clearwire today released a short video showing early results from the company’s trial of LTE and WiMAX technology in 10x10MHZ and 20x20MHZ spectrum configurations. Clearwire says the spectrum resources available to a carrier can be as important as the underlying network standard.
John Saw, Clearwire’s CTO, explained why these trials were conducted, why spectrum size matters, and what these trials mean for the future of Clearwire.
“Today we are simply conducting trials in order to plan for the future, see what’s possible, and consider all of our options. We’re a technology agnostic company – we always have been – and we’re focused on doing what’s best for the customer. Today that’s WiMAX. Potentially in the future that could be WiMAX and LTE. The great thing about our network is that it’s built in a way that if we did add LTE at some point we could reuse our existing core infrastructure, backhaul, and spectrum.
Clearwire’s majority owner, Sprint, will start selling a WiMAX-enabled BlackBerry PlayBook tablet. Sprint also sells the Samsung Galaxy Tab – but only on Sprint’s 3G network. Sprint will obviously need to implement 4G (WiMAX or LTE) tablets in the near future.
Sprint Nextel CEO Dan Hesse said their decision to opt out of further investment in Clearwire was a simple business decision and that nothing deeper should be read into that decision.
“Clearwire is our 4G strategy,” Hesse reiterated. “We will continue working with them going forward.”
Interestingly, he didn’t mention “WiMAX” in that sentence.
Keith Shaw of Network World rans some speed tests on Verizon’s LTE network, using the LG VL600 USB data modem, which can access Verizon Wireless’ new 700 MHz LTE network that uses 10 MHz channels.
In speed tests, he was able to achieve about 6-8Mbps of download speed, and almost the same (5-7Mbps) of upload speeds.
TeliaSonera’s LTE network, uses 20 Mhz channels in the 2.6GHz band, similar to Clearwire’s approach in Phoenix. Like Clearwire’s test, TeliaSonera can deliver speeds at up 59Mbps when used at 2.6GHz – but it also reveals how the technology sometimes struggles when used indoors.
With IEEE 802.16m, a single 20 MHz-wide channel can be used, combined with MIMO antennas for about 4X the speed in an upgrade that is backwards compatible with today’s devices. That could result in typical throughput rates of 25 Mbps (up from 6 Mbps).
That could be enough for internet television.
It’s tempting to think that a wireless carrier like Clearwire could compete with cable television operators like Comcast or T/W Cable, although the typical throughput per month could skyrocket from 10 GBs to over 100 GBs. The biggest obstacles may not be technical, as Google TV discovered.
