Feeds

Femtocells, not 4G, will solve spectrum crisis

Ofcom bets big on small cells

Boost IT visibility and business value

4G will improve capacity by only 1.2 times, according to the latest research, so better network topologies will be needed if we're going to get the bandwidth it seems we'll need.

Solving the widely anticipated data crunch will require better-designed networks, rather than new generations of radio standard, according to the latest research (PDF, surprisingly dull) carried out by Real Wireless on behalf of the UK regulator Ofcom.

The independent consultancy reckons that 4G (LTE) deployments will only improve spectral efficiency by about 20 per cent, despite offering much-improved speeds to individual users. So the best way to increase the overall capacity of the mobile networks is to build a lot more base stations rather than depend on magical new technologies to do more with less.

That conclusion isn't very surprising: the later versions of 3G (including HSPA and those other variants that Americans already call "4G") are very spectrally efficient. The limit on 3G is really a physical restriction on how much data one can squeeze into the 5MHz channel defined by the 3G standard.

Some extensions to that standard are already lashing together 5MHz channels for greater speed, but 4G (LTE) is much better at dynamically allocating a channel from 1MHz up to 20MHz in width depending on the application being used. That enables LTE to achieve headline-grabbing speeds for individual users, without being significantly faster than 3G.

The best way to carry more data, therefore, is to transmit it less far, so that frequencies can be reused more readily. If my nearest base station is 10 miles away, then the signal from that transmitter is sent into an area 50 square miles in size, while the one coming from my phone fills a circle of 314 square miles. Put the base station a mile away and those figures drop to a shade over a tenth of a square mile for the base station, and .8 from the handset.

Those figures are our own back-of-an-envelope stuff, but it is obvious that packing base stations closer together means frequencies can be reused more often, and thus the capacity of the network increases proportionally. LTE has many features to facilitate exactly that; OFDM reduces interference from neighbouring cells and LTE enables a very fast soft hand-off between cells, reducing the signalling load on the network.

So we will need 4G to make the future happen. Not because it can carry more data than its predecessors, but because it enables a greater density of base stations to be deployed. Good news for base station manufacturers, but bad news for those who want to know where all those base stations are going to go. ®

The essential guide to IT transformation

More from The Register

next story
UK fuzz want PINCODES on ALL mobile phones
Met Police calls for mandatory passwords on all new mobes
Canadian ISP Shaw falls over with 'routing' sickness
How sure are you of cloud computing now?
Don't call it throttling: Ericsson 'priority' tech gives users their own slice of spectrum
Actually it's a nifty trick - at least you'll pay for what you get
Three floats Jolla in Hong Kong: Says Sailfish is '3rd option'
Network throws hat into ring with Linux-powered handsets
Fifteen zero days found in hacker router comp romp
Four routers rooted in SOHOpelessly Broken challenge
New Sprint CEO says he will lower axe on staff – but prices come first
'Very disruptive' new rates to be revealed next week
US TV stations bowl sueball directly at FCC's spectrum mega-sale
Broadcasters upset about coverage and cost as they shift up and down the dials
Trans-Pacific: Google spaffs cash on FAST undersea packet-flinging
One of 6 backers for new 60 Tbps cable to hook US to Japan
Tech city types developing 'Google Glass for the blind' app
An app and service where other people 'see' for you
UK mobile coverage is BETTER than EVER, networks tell Ofcom
Regulator swallows this line and parrots it back out at us. What are they playing at?
prev story

Whitepapers

5 things you didn’t know about cloud backup
IT departments are embracing cloud backup, but there’s a lot you need to know before choosing a service provider. Learn all the critical things you need to know.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.
Rethinking backup and recovery in the modern data center
Combining intelligence, operational analytics, and automation to enable efficient, data-driven IT organizations using the HP ABR approach.
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.