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LTE is 4G – Forbes

LTE is 4G – Forbes

A man reads an advertisement leaflet that promotes China Mobile’s 4G iPhone 5s on the opening day of sales of China Mobile’s 4G iPhone 5s and iPhone 5c at a shop of the world’s largest mobile phone operator in Beijing, China, Friday, Jan. 17, 2014. (AP Photo/Alexander F. Yuan)

For once there is a logic in the acronym. The standards committee for 3G is called 3GPP, or 3G Partnership Program. Its job initially was 3G standards, and explicitly not anything which might come after. Discussion on what 4G might be was distinctly out of remit. But engineers, you know. So they called what they were discussing 3G Long Term Evolution. See it’s got 3G in the name and says “Evolution” it can’t possibly be about 4G.

Except of course it was.

Where LTE improved on the radio technology of 3G’s WCDMA is that it introduced OFDM or Orthogonal Frequency-Division Multiplexing. All the previous technologies had used a single carrier frequency, it might hop around a bit but the user hopped from one frequency to another. If you think of the data stream as being a hosepipe with the previous technologies you could only have one pipe at a time. With LTE you could have multiple pipes, what’s more pipes were a bit squidgy so they overlapped in frequencies. The effect was like moving from a 2D image to a 3D one.

While the previous Gs had launched with something of a fanfare the 4G technology for the 2010s just crept into phones. It was nothing like as expensive for the networks to move from 3G to 4G as it had been to roll out the previous technologies and while the extra capacity reduced the cost of calls and megabytes it was possible to just phase it in.

LTE was all about data, it moved mobile from having a voice channel with some data attached to having voice as an application which turned your voice into data. Indeed voice was so unimportant the standards bodies forgot to include it. The view was that if you wanted to make a call you’d install Skype or some other app to do it. Ultimately the powers that be realised their mistake and introduced VoLTE or Voice over LTE. Still, if you make a call on your 4G phone today it’s most likely that it will be a 3G call. This is a shame because for all the improvements in bandwidth the sound quality has lagged behind. GSM was optimised for the German, male voice.  GSM saw some improvements over its lifetime and 3G added Wideband AMR  which some networks sold as HD Voice but generally audio quality for calls stagnated. The standards committees failed to grasp this with 4G. In part this may be down to handset design. A 4G phone has lots of radios. There are over 40 different frequencies in the LTE spec and while no phone has them all there is still a huge need for lots of space to be taken up by the antennas they need. The vast majority of 4G phones also do 3G and 2G so just being a phone takes up lots of space. Add Bluetooth, wifi, cameras with flash, GPS, tilt sensors, NFC and fingerprint scanners and there is a lot of competition for space in a phone which consumers and marketing departments want as thin as possible. Although this year’s Samsungs are actually a shade thicker than last years. So everything is a compromise. Audio often takes the back seat. Putting in a speaker which sounds as good as a landline needs a lot of space. Speakers really want a big diaphragm and space behind them to work.

Behind the technology changes over the generations there had been big industry changes. In the 1G, 2G and 3G generations the industry had been vertically integrated. The companies which made handsets also made the chips within them and the mobile phone networks. When Orange launched it bought pretty much everything from Nokia. A Siemens network might have Siemens phones with Siemens chips in. The same was true of Ericsson, Nokia, NEC and others. Each manufacturer had it’s own software platform or platforms. Over time the companies separated out the divisions, which then were sold, merged with rivals or closed. Today the only major chipset vendors are the Chinese MediaTek and the American Qualcomm. While small specialists like nVida and Frontier exist they are really targeted at non-handset applications like ATMs, cars and industrial equipment.

There is some pioneering chip design by Apple which bought National Semiconductor, and both Huawei and Samsung have substantial chip design organisations. But even these companies buy from MediaTek and Qualcomm.

With the strength of these two companies has come homogenisation. Phones all look pretty much the same and have the same features. One of the major factors in this is that there are now only two operating systems: Android and iOS. All the others, Sailfish, Windows, Tizen, and the one which created the smartphone – Symbian – have fallen by the wayside.

The dominant handset manufacturers of 4G have been Samsung and Apple. As phones have become something everyone has the value of brand has overtaken innovation. Each year when new phones are launched the improvements are only incremental. Reviewers pretty much always say it’s not worth upgrading from last year’s model, but it is worth moving from the year before. With two-year contracts being the norm we’ve seen replacement rates tumble. Whence people got a new phone every nine months it’s now every 24. You tend to be either and odd model number or even model number person.

4G really saw the change from phones as phones to phones as computers. In the analogy where I’ve see 1G as being like vinyl records, 2G as CD and 3G as DVD, 4G is Blu-Ray. Not a huge change but that is to come. We’ll look at 5G tomorrow.

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