Today’s video-streaming, videoconferencing smartphones have an almost insatiable appetite for data. These devices don’t just sip bits, they gulp them down in a movable feast of apps, video and Web browsing. But all that data has a downside: surfing the once-wide-open 3G freeways can now seem like slogging through rush-hour gridlock. At times, even basic tasks on a smartphone can bring you back to the dial-up days, when Web pages took minutes to load. Enter 4G.
With promises of cable-modem-like speeds, these next-gen networks could change the way we use mobile devices. The first 4G networks are up and running in certain parts of the world. When 4G eventually reaches South Africa, should we think twice before signing the two-year contract?
So what is 4G?
First, a bit of history: 3G has been available since 2003. In the USA, these networks came in a jumble of competing standards from various carriers, offering download speeds ranging from 300 Kbps to 1,5 Mbps and turning phones into true data devices. South Africa’s enhanced 3G standard, also called 3,5G, using the HSDPA (enhanced high speed downlink packet access), offers speeds over 20 Mbit in selected areas.
The first 4G network in the US rolled out in select cities in 2008, and 4G gained serious momentum last year as more networks came online.
As you might expect, the higher the Gs, the greater the speed. (Those Gs, by the way, stand for “generation” as in “third generation”, “fourth generation”, etc.) But that doesn’t mean there’s a standard definition of what constitutes a 4G network. Like “natural flavouring” and “new and improved”, the 4G label is as much marketing as technology. “What defines 4G is a matter of opinion,” says Roger Marks, chair of the Institute of Electrical and Electronics Engineers broadband wireless working group. “There is no formal authority that decides what 4G is.”
As a result, cellphone networks have resorted again to a variety of different – and completely incompatible – technologies, all stamped with the 4G label.
Semantics aside, users can expect to get a substantial speed boost by switching to 4G. In recent testing, we found the 4G networks able to achieve real-world speeds ranging from 5,8 Mbps all the way to 24,3 Mbps.
How does it work?
Like 3G before it, 4G offers up an alphabet salad of standards. For the US market, Verizon is using LTE (Long Term Evolution); Sprint, in partnership with Clearwire, is behind WiMAX (Worldwide Interoperability for Microwave Access); T-Mobile is using HSPA+; and AT&T is offering a combination of LTE and HSPA+.
Each technology has its advantages. Verizon’s and AT&T’s LTE signals live primarily around the 700-MHz band, used for analogue TV broadcast. These relatively low-frequency signals can travel long distances and reach deep into buildings, meaning LTE devices should get a stronger signal in places such as basements and elevators.
The WiMAX network operates in the higher-frequency 2,5-to-2,7-GHz band. According to the IEEE’s Marks, WiMAX antennas should be able to handle more data traffic; this extra capacity should help avoid the sort of network overload that often chokes up and slows down today’s 3G networks.
HSPA+ networks offer less potential bandwidth than WiMAX or LTE, but they are easier to deploy. Because HSPA+ is essentially an upgrade to existing infrastructure, it will result initially in a far larger footprint than the select cities and airports typically covered by WiMAX and LTE.
Which technology will prove best? It depends on how 4G evolves. LTE is the fastest now, but that may not matter if it gets overcrowded with data-hogging users. And if plans to expand the footprint of LTE and WiMAX stall, the slower HSPA+ networks may come to seem like a smarter bet.
Which gadgets use 4G?
So far, there are three basic types of 4G devices: smartphones, USB modems and mobile hotspots that harness 4G service to create portable Wi-Fi networks for multiple devices. (Mac users, watch out: some of the USB modems we tested are Windows-only – check before you buy.) None of these devices can replace a home Internet connection yet (see “Home router test”), but our tests showed 4G speeds to be, at their best, good enough to tackle most high-bandwidth tasks, including streaming video from a variety of sources, such as Netflix, Hulu and YouTube.
There are also a number of laptops and tablets with 4G access built in. Although they may seem less expensive than a Wi-Fi-only version of the same device, they typically require users to sign a multiyear contract, which can add up to thousands of rand. And unlike a USB modem or mobile hotspot, their connections cannot be shared by multiple devices.
Since 4G network coverage can be limited, most 4G devices have the ability to fall back on a slower 3G network. This safety net isn’t just useful for people who find themselves outside of cities covered by 4G – even in 4G service areas, we found that devices frequently lost the speedier connection and got bumped down to 3G.
The 4G networks are power hogs that can strain a phone’s battery. “As 4G chipsets mature and we see more multicore devices, battery life should improve,” says Ross Rubin, executive director of industry analysis at market research specialists the NPD Group. Until then, many 4G phones give users the ability to switch off 4G to preserve battery life – something we found ourselves doing to get through a day between charges.
Sexy devices and fast networks are great – if you can stomach the monthly bill. The thing is, the cost of 4G can sneak up on you, even in the fiercely competitive US market. Zooming past a data cap can cause fees to add up quickly. One network charges $10 (R70) per gigabyte over its data caps. And the high speeds of 4G put those caps within surprisingly easy reach: just 3 hours of HD Netflix streaming will get you to the 5 GB monthly limit.
The drawbacks of 4G are many – limited equipment, spotty coverage, confusing plans – but temporary. Yet 4G networks do offer one huge benefit to early adopters: because these networks are new, they are still running under capacity. If you’re lucky enough to live in an area with coverage, using a 4G device today is like driving a Lamborghini on a new highway with light traffic. And that may not last. If the history of 3G has taught us anything, it’s that when carriers build capacity, users will come.
Real-world torture test
When it comes to the 4G future, speedy Web browsing is just the beginning. To see how the carriers’ new networks handle higher performance tasks, PM editors Glenn Derene and Seth Porges put the networks through a battery of tests designed to push them to their limits – and beyond.
HD video test To evaluate how 4G handles video, we used a Sprint mobile hotspot to stream Netflix to an Xbox 360. The result was stunning HD video – at first. After a few minutes, Netflix bumped us down to standard def (interrupting our movie). Minutes later, it was back up to HD, and then down again. Seems like 4G isn’t yet ready for home-theatre heavy lifting.
Home router test
Can a 4G network really replace a home wireless router? To find out, we set a houseful of Wi-Fi gear on a mobile hotspot running a 4G WiMAX network. Our test gear included a Netflix-streaming TV, two video-streaming computers (one playing YouTube, the other handling Hulu) and a Web-surfing iPad. On their own, each of these devices worked, at least intermittently. But when used all at once, Netflix skipped down from HD, Hulu lowered its frame rate to once every few seconds and YouTube slowed to a crawl. Bottom line: we’ll be keeping our cable – at least for now.
Whip-fast 4G networks should be a commuter’s dream. But how do the networks handle a laptop roaring along at 100 km/h in a train? We found that all three services we tested lost their grip on a 4G signal 50 km out of a big metropolitan centre. Despite coverage maps that show strong 4G signals along all or most of the route, the USB modems from all three carriers routinely reverted back to slower 3G connections as we sped away from the city centre.