Admittedly, mobile technology evolves at a very fast pace. But somewhere along the way we seem to have skipped an entire generation of networks.
This week Broadcom unveiled its first LTE chipset for mobile devices, but it wasn’t just any LTE chip, it was an LTE-Advanced chip. Sprint and T-Mobile were late to the LTE party, but that’s okay. They aren’t building any old LTE networks. They’re building LTE-Advanced networks.
Everywhere you look, some infrastructure vendor is bragging about its LTE-Advanced base station or some carrier is talking up its LTE-Advanced-capable network. With these claims, it’s hard to imagine that just two years ago plain-Jane LTE was on the cutting edge of mobile technology.
It’s all hogwash.
You may remember that a few years back T-Mobile and AT&T magically transformed their HSPA networks from 3G systems into 4G systems by waving their marketing wands. That technology inflation, however, began years began years before when Sprint first attached the 4G moniker to its WiMAX networks.
Even today, mobile technology purists would argue the world has yet to see its first 4G network, since no carrier system yet meets the original 4G guidelines established by the International Telecommunication Union. Instead of condemning the industry’s fast-and-loose play with the term, the ITU simply caved, retroactively defining 4G as pretty much anything the carriers wanted it to be. 4G has always been an iffy term, but after the ITU dropped the ball it became a meaningless one.
Now the same thing is happening with LTE. In an effort to seem more progressive than their competitors, carriers, infrastructure vendors and chipset makers are finding loopholes in the technical standards to elevate their LTE technologies to the rarified status of LTE-Advanced. Basically, the industry is carrying around a Cadillac keychain but it’s really driving a Buick.
For a more detailed explanation of what LTE-Advanced actually is, you can check out these posts from Stacey Higginbotham and me about the technology’s nuts and bolts (If you’re a GigaOM Pro subscriber there’s also this more in-depth piece). Here’s the general twist: LTE is an iterative technology much like 3G HSPA before it. Just as the industry started out with slower UMTS networks and migrated to faster HSPA and HSPA+ systems, LTE will go through the same evolution process over the next decade or so.
With each new step on that evolutionary path, downlink and uplink speeds will get faster and more resilient, latency levels will drop and overall network capacity will balloon. At some point we’ll follow that path into a set of technologies and techniques that the mobile standards bodies have defined as LTE-Advanced.
We’ll start seeing big changes in how cellular networks and devices are designed. Infrastructure and handset makers will start bolting multiple pairs of antennas onto their towers and devices. Carriers will be able to bond disparate bands of spectrum together to create super-connections. Small cells and Wi-Fi access points will merge into the fabric of our big umbrella cellular grids creating the heterogeneous network. But we’re nowhere near that point today.
The devil is in the technical specs
It’s important to note that LTE-Advanced isn’t a monolithic technology, it’s really a collection of technologies. You can think of LTE-Advanced as a menu, from which carriers will order from depending on their needs. Some will order up the improved air interfaces, while others will munch on multiple antenna or advanced interference mitigation techniques — many operators will do all of the above.
One operator’s LTE-Advanced is going to look very different from another operator’s LTE-Advanced, but there are some minimum guidelines. One of those guidelines is the amount of capacity the network will support over a single 20 MHz swathe, or “carrier,” of spectrum. According to the standards group that defines these things — the 3GPP — at the very least an LTE-Advanced carrier should deliver more than 300 Mbps of downlink capacity or more than 50 Mbps of uplink capacity.
I’m going to pick on Broadcom for a minute, only because it happens to be the most recent offender. In its materials, Broadcom clearly states its super-chip supports 150 Mbps on the downlink and 50 Mbps on the uplink. Impressive, yes, but it’s not LTE-Advanced. What Broadcom has built is known in industry parlance as an LTE user equipment category 4 chip. LTE-Advanced doesn’t start until category 6. This is fairly technical, but take a look at this chart of user equipment categories compiled by Wikipedia editors (A quick reference guide: Release 8 is LTE and Release 10 is LTE-Advanced):
Broadcom is only halfway to even the minimum definition of LTE-Advanced’s speed specs of 300 Mbps. The same goes for Qualcomm and any other LTE chip vendor. In fact, today’s networks are right smack in the middle of the regular LTE standard (maxing out at 100-150 Mbps on the downlink), and they’re probably going to remain that way for some time.
So how is everyone getting away with calling their products LTE-Advanced? Why, through marketing of course. They’ve latched onto a single spec in the LTE-Advanced standards, a technique called carrier aggregation. Carrier aggregation is the super-connection technology I mentioned earlier, and in truth it’s older than the hills. T-Mobile and many other global carriers already use it in their networks to support their 42 Mbps services.
By boasting technical support for carrier aggregation on LTE networks, marketers have made the huge leap to LTE-Advanced, which is ridiculously misleading. It’s the equivalent of ordering a Coke and then claiming you’ve indulged in a full meal.
We’re going to get to LTE-Advanced eventually, and those networks will be truly awesome. But the industry isn’t doing itself any favors by promising us technology it can never deliver. It’s 4G’s overhype all over again, and it needs to stop.
Feature image courtesy of Shutterstock user B & T Media Group Inc.