Wireless Waffle - A whole spectrum of radio related rubbish
Is 5 better than 2.4 (GHz)?signal strength
Thursday 9 August, 2012, 15:13 - Radio Randomness, Spectrum Management
Posted by Administrator
wi five logoAlthough the standard for WiFi at 5 GHz has been around for a long time, most manufacturers have focused upon producing equipment for the 2.4 GHz band. The reason for this is a simple one - it's cheaper! The higher you go in frequency, the more difficult, and therefore expensive, it becomes to transmit and receive radio signals. As a result, home routers, laptops, smart phones and other devices have almost exclusively been equipped to use the 2.4 GHz band for their WiFi connection.

Previous Wireless Waffle articles have discussed how to select the best WiFi channels in the 2.4 GHz band, and other techniques, to maximise coverage and signal quality, however we have not looked at the 5 GHz band. Recently, there seem to be a slew of articles which are claiming that using 5 GHz will produce better range and more reliable connections compared to 2.4 GHz. The logic of these articles seems to go '5 is a bigger number than 2.4 - in fact it is more than double - so it must be at least twice as good'. This, sad to say, is not the case. Here are the real facts:
  • Signals at 5 GHz only travel HALF as far as those on 2.4 GHz as higher frequencies have poorer coverage than lower ones.
  • Signals at 5 GHz will struggle almost TWICE AS HARD to get through walls than signals at 2.4 GHz due to their poorer propagation characteristics.
  • 5 GHz WiFi equipment is subject to exactly the same POWER RESTRICTIONS as that for 2.4 GHz, so there is no inherent advantage in terms of the technology itself.
  • The use of some of the 5 GHz channels is subject to the requirement to STOP TRANSMITTING if a nearby radar is detected. No such restriction applies at 2.4 GHz.
  • 5 GHz equipment will be (slightly) more POWER HUNGRY than its 2.4 GHz counterparts, increasing battery drain especially in mobile devices.
  • 5 GHz receivers are likely to be LESS SENSITIVE than 2.4 GHz receivers because of the increased difficulty of making low noise devices at higher frequencies.
  • The 5 GHz band consists of up to 25 (territory dependent) independent channels which can be used without interfering with each other meaning there is much GREATER CAPACITY for more networks, whereas the 2.4 GHz band has 13 channels of which only 3 can be used independently.
  • The 2.4 GHz band is also used for Bluetooth, microwave ovens, wireless cameras and many other applications meaning it can be subject to a lot of background interference. The 5 GHz band is MUCH CLEANER, though the band is not exclusive to WiFi systems.
  • There are still fewer 5 GHz devices around than 2.4 GHz once and hence it is likely to be LESS SUSCEPTIBLE TO SNOOPING.
As coverage is determined both by signal strength and by the amount of interference, it is therefore possible that people in particularly densely populated areas where there are lots of 2.4 GHz users around might find that the 5 GHz band provides a more reliable connection and may even provide greater coverage. In most cases, however, the 2.4 GHz band has many advantages and the claims being made that 5 GHz is somehow 'twice as good' are just plain wrong.

For a home network, in a small house or apartment, using 5 GHz may offer some advantages given the lower interference it will suffer from other devices, but in large family homes a 5 GHz WiFi router is unlikely to be able to outperform the coverage and range that a 2.4 GHz router achieves.

five is betterWhere the 5 GHz band may come into its own is when the not-quite-yet-finalised IEEE 802.11ac standard is adopted. This works in the 5 GHz bands and uses the greater capacity of the band to deliver connection speeds of up to 1 Gbps. For streaming media around, this has clear advantages. As a wireless distribution for a home internet connection, however, there is unlikely to be any improvement noticeable using 802.11ac than with the existing 802.11n standard which can already offer connections of over 100 Mbps - much faster than most home internet connections!
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Gareth Emery feat. Christina Novelli - Concrete Angelssignal strength
Wednesday 4 July, 2012, 21:40 - Chart Predictions
Posted by Administrator
Another random pop prediction from the Wireless Waffle team. This time it's Southampton's very own Gareth Emery who has teamed up with the daughter of television chef Jean-Christophe Novelli to cook up a delightful tune called 'Concrete Angels'.

It seems unlikely that this will ever truly make the charts (not least it was released 5 months ago and is yet to challenge the chart countdown). But here at WW we thought that the clever use of the lights in tower blocks to represent electronic volume meters was pretty suave. Definitely a late night tune, headphones on, lights out, eyes closed. Or is that just us?
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Fjarskip taste of nunsignal strength
Monday 4 June, 2012, 21:29 - Much Ado About Nothing
Posted by Administrator
A friend recently alerted us to the fact that 'fjarskiptastofnun' is the Icelandic word for 'telecommunications'. Is this the best word for 'telecommunications' you have ever heard? Maybe, then again maybe not. Here are Wireless Waffle's favourite foreign phrases for the word 'telecommunications'.

Armenian: Հեռահաղորդակցման
Finnish: tietoliikenne
Georgian: სატელეკომუნიკაციო
Hungarian: távközlés
Irish: teileachumarsáide
Maltese: telekomunikazzjonijiet
Nonsense: dreskidooloo beepbeep
Swahili: mawasiliano ya simu
Vietnamese: viễn thông
Welsh: telathrebu by there, see?
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Pirate Radio disposal squad called into action in Surreysignal strength
Sunday 27 May, 2012, 17:50 - Pirate/Clandestine
Posted by Administrator
A report recently arrived on the Wireless Waffle newsdesk of the discovery of some kind of (probably illegal) transmitter discovered on land in Surrey next to a military establishment. According to the report:
Army bomb disposal experts were called to Camberley on Monday morning to deal with a "suspicious" object that turned out to be a radio device... Shortly before 3pm, Surrey Police said the unit had been confirmed to be a "transmitter or repeater for a citizen or pirate band radio station", and that roads had been reopened and cordons lifted.

Of course this piqued the interest of the Wireless Waffle team. Let's look at the possible options:

CB Repeater
Such things do exist but require a great deal of technical skill to install and operate. As CB radio operates at 27 MHz, they generally require large antennas, and as transmitter powers are usually at least 4 Watts, need power supplies the kind of size that wouldn't easily be left lying around in a piece of woodland.
Probability rating: ***** (2 out of 5)

Pirate Repeater
Not something that is often heard of, in fact, do a 'google' search and nothing of any substance comes up. One possibility is that it could have been a PMR446 repeater which, whilst not strictly legal, is not fully pirate as it operates on an unlicensed basis. Such devices would (sensibly) be located on high ground, though they could be operated from batteries for some time. Ideally, they would be high off the ground too (the news report does not indicate whether the so-called repeater was on the floor or up a tree).
Probability rating: ***** (1 out of 5)

FM Pirate Transmitter
piratelistenerMost FM pirate stations in the UK use transmitters on top of tower-blocks. The area in question is clearly not one bedecked with such skyscrapers, it is woodland. It is not unheard of for pirates to put transmitters up trees but there are better places, especially those with power and somewhere dry to put the transmitter. There aren't that many pirates in this area, Point Blank FM was one which used to broadcast specifically to the area but it hasn't been on air in that part of the world for many months. Pressure FM (also known as 'Presha') is another station in that part of the world. It is possible they would use a site such as that, but if they were locals, presumably they would know the area was largely military and steer clear of it?
Probability rating: ***** (4 out of 5)

Short-Wave Pirate Transmitter
Short-wave pirates are almost uniquely confined to woodlands in order to string up the large antennas necessary given the frequencies they use. They often use hidden battery powered equipment. On the face of it then, this is exactly the kind of place you would expect to find such a transmitter. The bigger question is whether any such pirates operate from that part of the country, the answer to which is, of course, 'who knows?' Certainly there is some history in the area including Radio Fax which used to operate from Surrey in the late 1980s, and of course, the infamous Radio Jackie which used to operate from the London end of Surrey. There's also a vague recollection of a maildrop for short-wave pirates that was in that part of the world (though my memory is a bit hazy on that). Anyhow, it's not impossible but the number of UK-based short-wave pirates seems very much in decline.
Probability rating: **** (3 out of 5)

Our conclusion then - probably an FM pirate - but a bit of a stupid one to go so near to ministry of defence land!
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