LTE Issues

Light Reading published an article based on discussions from the LTE World Summit. Carriers there identified a number of issues that need to be resolved before they deploy LTE, including:

• Support for voice and SMS services including circuit switching as well as packet switching.
• Building enough back haul capacity into the network to realize LTE's performance promises.
• Intellectual property rights.
• Spectrum

Much of this discussion revolved around lessons learned from 3G. It does point out the real problems carriers will have rationalizing both their 3G and 4G strategies. I think that they will either stay with 3G or replace their 3G networks with 4G networks. I think that trying to provide both will be a real mess.

Verizon to Deploy 4G by 2014

Light Reading has published a Verizon interview that states that the timetable of Verizon's planned LTE deployment of a couple of test markets in 2009 and "30 or so" markets in 2010. He then suggests that the build out could be completed relatively quickly after that.

This is an aggressive deployment schedule and I expect that it will be 2012 or 2013 before Verizon's 4G build out is complete.

Nokia Siemens Introduces Multi Radio BTS

Nokia Siemens has introduced a based station that will support GSM, WCDMA, HSPA, and LTE. It includes integrated Ethernet switching and transport. It expects to ship this system starting in 2011. This base station significantly reduces power requirements at 790 watts.

This is the kind of system that will facilitate the operation of multiple networks (2G, 3G, and 4G) as well as the evolution to 4G for all services. I expect to see other major vendors to introduce similar systems.

U.S. Delay in Analog Sunset

The U.S. will delay the completion of the conversion to digital broadcasting from February 17, 2009 to June 12, 2009. This will allow stations to continue their analog broadcasts until that date. There are more than 1,000 stations that have permission from the FCC to shut off their analog broadcasts on February 17. Nearly all stations will have to do it by June 12.

This shows what a mess the cessation of analog TV broadcasting can be. Frankly, I don't think it will be much better on June 12. This move is going to cause problems for a lot of people who have not prepared for themselves. I doubt three more months will change much.

This will delay the availability of 700 MHz spectrum for mobile applications. I expect that Verizon will use this as an opportunity to move its LTE trial to 2010 and commercial deployment to 2011.

Altair 4G OFDM Chips

I recently spoke with Altair, which is an Israeli company that is building OFDM chips to support both WiMAX and LTE. It is focusing on 4G technologies by building handset chips. The company currently has chips for WiMAX and for XGP, which is an OFDM technology deployed by Willcom in Japan.

Altair plans to introduce an LTE chip in the middle of 2009 and a multimode chip by the end of 2009 that will support WiMAX, XGP, and LTE. This will enable support of all three technologies in a single hand held device. The company is also working with a 2G/3G supplier to offer the ability to add WiMAX, XGP, or LTE to a 2G/3G device using the Altair chip as a coprocessor.

This is interesting because it shows that progress is being made on chips that will facilitate the integration of 2G, 3G, and 4G WiMAX and LTE networks. This will help with the evolution of existing networks to WiMAX or LTE. It may also facilitate roaming between WiMAX and GSM, WCDMA, and LTE networks, which may keep WiMAX from becoming the dead end that CDMA has become.

T-Mobile Sets Standards for LTE

Light Reading published an article that discusses statements from T-Mobile about what they are looking for in LTE. T-Mobile believes that the cost to deliver a Mbps must go down by a factor of 10 because data traffic is increasing at a higher rate than revenues. It also wants LTE networks to be self-organizing and to be software upgradeable.

T-Mobile also believes that femto cells will be important for extending coverage. It also is looking for the early availability of mass market LTE terminals.

T-Mobile plans to go to Ethernet backhaul either over high-speed wireless links or optical links to keep network costs down.

All of these are clear requirements for LTE. Without these, there will be no reason to upgrade from 3G.

Will Femto Cells Rule LTE?

A Light Reading article describes a picoChip presentation that femto cells will be used rather than macro cells for 4G LTE deployments. picoChip believes that the reduction in speeds that come at longer distances will require reducing cell radii in order to keep performance high. It states that its femto cell technology will solve this problem when used in place of macro cells.

This is an interesting minority position. The mobile operators seem to be adopting a macro cell LTE architecture. However, picoCell's point is a good one. The recent 3G iPhone experience is showing that there is low user tolerance for major variation in data performance across wireless networks.

China Mobile Poised to Jump to 4G LTE

A Light Reading article stated that China Mobile is poised to jump to 4G LTE before it has widely deployed its 3G TD-SCDMA network. It plans to launch LTE in 2010 and says that 60 percent of its TD-SCDMA investment will migrate to LTE. It plans to use TD-LTE, which uses spectrum in a similar manner as TD-SCDMA.

It will be interesting to watch how this situation progresses. I think the transition will be more problematical than this article indicates, but it show that China Mobile recognizes that 4G LTE is the right technology in the long run.

Qualcomm Backs LTE

Qualcomm will abandon its UMB 4G technology in favor of LTE. UMB was intended to be the 4G evolution for its CDMA and EV-DO customers.

LTE has been accepted by most of Qualcomm's CDMA and EV-DO customers as their 4G technology choice. UMB has received little or no support. By removing UMB from the table, it seems clear that LTE will dominate the 4G mobile networks. WiMAX has been adopted by some but is likely to be used more for wireline broadband replacement services in under served areas.

White Space: Taking the Internet Back to the Future?

The FCC decision this week to open up the TV "white spaces" to unlicensed wireless services has great potential to break the hammer lock that the cable and Telcos have on the consumer Internet business today.

Ten years or so ago, before the advent of cable modem and DSL services, there where hundreds, if not thousands, of ISPs providing dial up consumer Internet access. There were a few large ones such as Prodigy and AOL along with many, many small providers. It was easy and inexpensive to set up a dial up ISP service. Get a T1 line and attach a dial up mux, and you were in business.

The advent of broadband services brought this to an end. The cable modem and DSL services had the ISP service bundled in with them. This gave the cable companies and the Telcos a strong strategic advantage. AOL continues to exist, but is a shadow of its former self. EarthLink provides Internet services on top of Telco DSL services, but has a very small share of the market. Almost all broadband Internet users subscribe to cable or Telco Broadband services.

The white spaces spectrum is the UHF TV spectrum that is not being used to broadcast TV content. There is generally 100 MHz of vacant spectrum that can be used for white spaces applications in the major metro areas. There is 200 MHz or more of vacant spectrum in more rural locations. This is enough to support several ISPs that want to offer services.

WiMAX and LTE 4G technologies can support wireless broadband data services that will provide a 1 to 5 Mbps. This will compete well with broadband cable and DSL services. These wireless services will share the conveniences of mobile voice service that have made them popular. These white spaces services have the potential to dominate the low end of the broadband data market. People will like their personal nature and their go anywhere convenience.

This will drive the cable companies to DOCSIS 3.o and the Telcos to fiber, which will give us all that still want them much higher performance on our home broadband services. Enabling start ups to compete will be a good thing for all of us consumers.

T-Mobile to Adopt LTE

Light Reading has and article that describes T-Mobile's wireless network evolution plans. T-Mobile plans to continue to make software upgrades to its HSPA network to improve its performance; however, the company will not make hardware upgrades. Instead it will move to LTE at that point.

With software upgrades, T-Mobile can boost its current 7.2 Mbps HSDPA network up to 14.4 Mbps on the downlink. Beyond that, HSPA Evolution (or HSPA+) can boost 3G network speeds to 28.8 Mbps or more but requires MIMO antennas. That is where T-Mobile draws the line.

T-Mobile also stated that it is considering deploying TD LTE in currently unused TD spectrum that it owns in Europe.

T-Mobile's approach makes sense. It will put them onto the OFDM track earlier than later.

The 4G Conundrum

The announcement by Cox Cable this week that it is going to build two wireless networks as well as utilize Sprint's wireless network got me thinking again about what I call the 4G Conundrum. I just don't understand how 3G and 4G networks will coexist.

Both 3G and 4G networks will be targeted to the same set of users: laptops, smart phones, and the iPhone class of handsets. Sure, operators can deploy 4G in areas were there is a high level of 3G use as a more economical way to add capacity. But it they provide higher speeds on these 4G hot zones, people will see a significant decrease in speed when they move to a 3G zone. The recent problems with iPhones on the ATT network show that these uses see this kind of performance decrease as a network failure. I think that this kind of zone based 4G deployment will just not provide the level of service that the Internet heads that use iPhone like devices will want.

The other thing is that 3G HSP continues to be enhanced. Performance is getting better. These advanced 3G networks are adopting the same flat IP architectures that is part of 4G networks. The question here is if 4G is really enough better than these advanced 3G technologies to justify deploying it.

There is one situation where the the case for 4G seems clear. The CDMA operators are moving to 4G LTE technologies to enable international roaming. Today the lack of international roaming is a big disadvantage for CDMA operators compared to GSM/WCDMA 3G operators. Verizon is adopting 4G LTE as are many other CDMA operators.

I do think that nearly all carriers will migrate to 4G LTE by 2020. There will be a few such as Sprint and Korea Telecom that will operate WiMAX 4G networks. It is very likely that handsets will be able to support roaming between WiMAX and LTE by that time. Operators will bite the bullet as HSPA's WCDMA reaches its limits and is surpassted by 4G OFDM technologies.