Making sense of 4G and other myths

If you're confused about 4G, welcome to the fastest-growing club! AT&T claims to have the nation's largest 4G network. Verizon touts America's fastest 4G LTE network with "a higher standard of coverage." The advertising war is on. AT&T recently befuddled millions of iPhone 4S customers. After upgrading to iOS 5.1, users discovered that the 3G network indicator next to the signal bar had mysteriously changed to 4G. Many thought, "Lucky me!" Not so fast. Since the carriers and gadget makers won't call the whole thing off, it's time to take a fresh look at the state of 4G. The term 4G refers to the fourth generation of cellular wireless technology. It all began in the 1980s with those 1G analog wonders that were the size - and weight - of a brick. Late, digital networks allowed users of 2G cellular phones to send text and email. 3G networks, of course, ushered in the age of smartphones and data. With 4G technology, the distinction between voice and data goes away. It essentially turns a cellular phone into a Voice-over-IP system. That means faster, clearer communication. How fast? The International Telecommunication Union defines 4G as the ability to download data at speeds of 100 megabits per second to 1 gigabit per second. The 1Gbps standard is for home and low-mobility situations, such as someone walking around with a phone. The 100Mbps standard is the theoretical maximum download speed that a user traveling in a car or train would experience. Although current networks in the U.S. are nowhere near those kinds of speeds - and won't be for a few more years - the rollout of 4G LTE is an important interim leap. LTE (Long Term Evolution) theoretically maxes out at 100Mbps. Real-world speeds are more like 20Mbps or less. Mobile Internet speeds can vary greatly from one location to another. Cell towers are scattered, and when many users are connected to a tower at the same time, speed bogs down. Still, LTE speeds can put some home broadband connections to shame. Verizon has brought 4G LTE to more than 200 million people in 203 cities. More than 260 million customers in 400 markets will be able to access 4G LTE by the end of the year. AT&T's 4G LTE network is live in 28 markets. The carrier expects to complete its LTE network by the end of 2013. Sprint customers in Baltimore, Kansas City, Dallas, San Antonio, Houston and Atlanta are slated to receive 4G LTE service by mid-2012. T-Mobile will launch 4G LTE next year. If you're an AT&T customer in a city that doesn't have LTE yet, your 4G is actually HSPA+. T-Mobile 4G users are also on a HSPA+ network. Current Sprint 4G customers, meanwhile, are using the WiMAX standard. Although marketed as 4G, HSPA+ and WiMAX are more like souped-up 3G. If you're going to be buying a smartphone in the near future, it's important to know exactly what you're getting. If it's an HPSA+ or WiMAX phone, it'll only be a little faster than 3G. It's also a good idea to check whether you're in a 4G LTE coverage area (or will be soon). AT&T says the iPhone 4S can take advantage of its HPSA+ network speeds. However, the phone doesn't have the chipset that would allow it to join a true 4G LTE network. The new iPad does. But it's currently only compatible with the 700MHz and 2,100MHz LTE bands that North American carriers use. That's why the 4G LTE iPad doesn't work in Australia; carrier Telstra uses the 1,800MHz frequency. This points out what could be a looming problem for globe-trotting Americans. In order to feed the mobile data beast, carriers in Europe and elsewhere may adopt entirely new bands as they build out their 4G networks in coming years. Your "world" 4G smartphone or tablet may revert to slower standards if it isn't compatible with some of those new frequencies. So, are you ready for 5G?