Wireless Waffle - A whole spectrum of radio related rubbish
Hear no Alien, See no Alien, Speak no Aliensignal strength
Tuesday 18 April, 2017, 15:37 - Radio Randomness
Posted by Administrator
alien radio transmissionsHere at Wireless Waffle, we have taken quite an interest recently in deep space communication with Mars and Jupiter and the search for extra-terrestrial intelligence (SETI), considering whether we are, for example, listening on the wrong frequency.

It seems, however, that even the professionals are having difficulty in detecting any signals from remote solar systems. The Guardian newspaper reports that 'the most ambitious alien search to date draws a blank'. The Breakthrough Listen project had found a number of promising signals, however despite innovative software and algorithms and $100 million of funding, all of these turned out to be terrestrial in origin.

At the same time, whilst we are listening, should we not also be attempting to transmit signals for others out in the great black beyond to receive. After all, no-one would know that we are here unless we shout about it.

Many fear the consequences of us raising awareness of our existence. They claim that if we were to announce to the universe that we are here, 'minds immeasurably superior to ours would regard our Earth with envious eyes' (to paraphrase HG Wells). The 2015 Hugo award winning novel The Three-Body Problem by Cixin Liu explores this precise issue (as well as providing a tantalising glance of a futuristic on-line game designed to route out only the most intelligent). Originally written in Chinese, the book picks up the story of a remote Chinese 'radar' station whose function is not quite as navigational as it seems. It's in the process of being made into a feature length movie too (albeit in Chinese).

It stands to reason, however, that if we shy away from transmitting the occasional signal to alert anyone that is listening that we are here, it would be logical to assume that any other intelligent civilisations may have taken the same cautious approach. Hence we will never hear from them and they will not hear from us. This doesn't mean we should give up, but it does question the logic of listening intently, whilst not speaking.

hear speak see no alien
add comment ( 53 views )   |  0 trackbacks   |  permalink   |   ( 3 / 15713 )

A Jovial Receptionsignal strength
Wednesday 29 March, 2017, 09:15 - Radio Randomness, Spectrum Management
Posted by Administrator
Wireless Waffle has previously discussed the idea that it might be possible to receive radio transmissions from alien planets, but it might not be widely recognised that it is possible to receive radio transmissions from planets within our very own solar system!

mobile phone on jupiterIt turns out that the planet Jupiter emits a range of different radio transmissions, not from people using mobile phones on the planet's surface, but so called long 'L' bursts and short 'S' bursts which are generated by the planet itself and its interaction with its moons, and that these signals are relatively easy to receive here on good old planet Earth. These emissions range in frequency from a few kHz to around 40 MHz. The Jovian signals get weaker the higher in frequency you go, but the lower frequencies are often absorbed by the Earth's ionosphere. In addition, many of these frequencies can be replete with short-wave transmissions. What is needed, therefore, is a frequency that is high enough to pass relatively unperturbed through the ionosphere, but low enough to be receiveable, without too much interference.

An obvious place to start would be the Radio Astronomy frequency allocation between 25.55 and 25.67 MHz as these frequencies should theoretically be free of all other radio transmissions. But it seems the frequency of preference for catching the latest bursts from Jupiter is actually 20.1 MHz, which is the frequency selected by NASA's Radio Jove project. From a radio spectrum perspective this is a relatively odd choice of frequency (e.g compared to the theoretically clean Radio Astronomy allocation). At an international level, frequencies around 20.1 MHz are allocated primarily to the fixed service, with a secondary allocation to mobile services. A quick scan of the Globaltuners database shows AT&T usage on 20.095 MHz and US Civil Air Patrol on 20.107 MHz. However, it seems that the signals from Jupiter at higher frequencies are much weaker, even by the time 25 MHz is reached.

radio jove antennaSo what do you need to listen to these mysterious signals? A simple short-wave radio should do the job, however it is said that there are two additional things which need to be done in order to tune in to Jupiter:
  • Turn off the AGC (automatic gain control) on the receiver. The AGC apparently tends to mask the bursts. A software radio is ideal for this.
  • Build a simple directional antenna.

The latter of these is the most difficult. A two-element array is what the experts say is needed, and at 20 MHz, this is roughly 8 metres (26 feet) square as the diagram on the right shows.

Notwithstanding a lack of the correct antenna, Wireless Waffle sought to attempt to receive Jovian radio signals using a short-wave receiver and a normal short-wave antenna (not the fancy two-element arrangement). Sadly, our attempts did not yield any L or S bursts that could be definitively identified as transmissions from Jupiter. We did however manage to receive:http   allbum it  ash girl from mars remixSo though we failed to receive any Jovian signals, we did receive some jovial ones and therefore maybe it wasn't such a pointless exercise as at first it might have seemed! Why not give it a go yourself and let us know how you get on?
2 comments ( 163 views )   |  0 trackbacks   |  permalink   |   ( 3 / 3320 )

Repairing Skin Laxity with Radio Wavessignal strength
Friday 30 September, 2016, 15:57 - Radio Randomness, Much Ado About Nothing
Posted by Administrator
kylie minogue red dressVarious media outlets reported that singer Kylie Minogue (and other famous television personalities) are using radio waves to get a facelift. At Wireless Waffle we like a good radio related story and if it involved Kylie then we are triply interested.

So what are the 'collagen waves' that the report claims are giving Ms Minogue her youthful look? It turns out that it is not strictly radio waves that are being used, but that very high frequency ultrasound is to blame. There are several articles online with titles such as: Reading these articles carefully it seems that the method of treament is:
to induce thermal damage to thus stimulate neocollagenesis in deep layers of the skin and subcutaneous tissue

So, effectively, the treatment causes damage to the various bits of the skin under the surface, presumably older bits, and the body then repairs the area, presumably with new bits. This is done by introducing:
a selective and controlled rise in tissue temperature.

Wireless Waffle decided to test the approach using similar equipment available in our test facilities using the following, scientifically accurate procedure:
  • First we took the only thing hanging around that needed an improvement in its 'skin laxity' this being a chicken thigh that was in the fridge destined for a nice casserole or being barbequed.
  • As we did not have 3 MHz ultrasound equipment available, we opted instead for the 2.4 GHz waves induced by our microwave oven.
  • It is also said that Ms Minogue uses Pond's cream to improve her skin tone. To replicate this, we coated the chicken thigh in a layer of mayonnaise.
  • As the areas surrounding the face will absorb some of the radio signal, we placed the chicken thigh on some cold, pre-cooked pasta and a few carrots and a piece of broccoli to simulate the neck and shoulders.
  • As the power levels used for the collagen wave treatment are claimed to be between 50 and 200 Watts, and as our microwave was 900 Watts, we set it to '10%' to simulate a 90 Watt collagen wave signal.
After 30 minutes of 'treatment' we concur with the studies which say that the sub-dermal tissue's temperature had been raised and that skin laxity is improved. Indeed the skin was tightened and nicely coloured, and the chicken thigh was plump and tender, and very tasty to boot.

collagen radio waves   ultrasound collagen waves
Before   After
It therefore seems very plausible that the reason Ms Minogue remains to tasty as she approaches her 50th birthday is due to the application of high power ultrasound radio-waves. Maybe others would like to replicate our experiment and report back on how tasty they were able to make their thighs.
add comment ( 40 views )   |  0 trackbacks   |  permalink   |   ( 3 / 342 )

SETI listening on the wrong frequency?signal strength
Friday 27 May, 2016, 03:40 - Radio Randomness, Spectrum Management
Posted by Administrator
Since the 1980s, extensive amounts of time and resources around the world have been focussed on the search for extra-terrestrial intelligence (SETI). One of the primary methods of doing so, is listening for radio transmissions from far away worlds. But how do you decide what frequencies to listen on?

alien lightning 2The main frequency that SETIologists believe would be the primary real-estate for aliens wishing to make themselves known is around what is termed the 'water-hole' at frequencies close to 1.5 GHz. This frequency range includes the so-called hydrogen line (1420.4 MHz) and hydroxyl line (1666 MHz) which are frequencies that are generated by naturally occuring processes within atoms. The other advantage is that Earth's atmosphere, which comprises quite a large percentage of water, is relatively transparent at these frequencies making Earth based observations easier. The logic is that any intelligent life would be as aware of these lines in the spectrum as we are, and would figure that these are good places to transmit. Whether the transparency of the atmosphere at these frequencies on the planets they inhabit would also point them in the direction of the water-hole is a moot point.

Other frequencies that have been considered are twice the water-hole frequencies (after all, intelligent life would surely be able to multiply by 2 - assuming their number system used the same integers as we do), or 4.462 GHz which is the hydrogen line times pi (because circles are a universal phenomena, right?)

But could we actually receive a transmission on such a frequency? Let's do the link budget calculation...
  • The path loss from our nearest star, Alpha Centauri, which is 4.37 light years (41,315,094,156,000 km) away at 1.5 GHz is 368 dB.
  • If we use a BIG dish, say 30 metres in diameter, to receive the signal, it would have a gain of 51 dBi.
  • Let's also assume that the aliens are transmitting using a similar sized dish (and they are pointing it directly at Earth).
  • If the signal is very low bandwidth data (say 100 bits per second) we would need a receiver bandwidth of around 100 Hz, giving a noise floor for a cryogenically cooled receiver of -168 dBm.
  • The necessary transmitter power to overcome the noise is therefore 368-51-51-168 or 98 dBm or 6.3 MegaWatts.
A 6.3 MegaWatt transmitter is not out of the question at these frequencies, so in theory, it might be possible. Of course planets orbiting more distant stars would need even bigger transmitters and the one slight flaw in this calculation is the need for the aliens to be pointing their dishes directly towards Earth. Take this out of the equation and you need a transmitter 51 dB bigger, meaning a transmitter power level of around 800 GigaWatts would be needed, even at Alpha Centauri, if an omni-directional transmit antenna was used.

But path loss is dependent on frequency, and so if a lower frequency was used, say 100 kHz instead of 1500 MHz, the path loss (from Alpha) drops from 368 dB to a more managable 284 dB (84 dB less). Unfortunately the gain of the receive dish also falls from 51 dB to a measly -33 dB (also 84 dB different). But instead of a dish, we could use a long-wire to receive the signals, at 1.5 km long, it would have a gain of 2 dBi, so overall we would gain 33 dB in our link budget calculation.

"A-ha", you say, "but the transmitting antenna would have a lower gain too, so nobody really wins. If I do the maths right, the required transmitter power is now 284+0+0-168 which is 116 dBm or 400 MegaWatts, which is a bit far fetched isn't it?" Maybe, but it's easier to generate 400 Megawatts at 100 kHz than it is at 1.5 GHz (or it is for humans anyway). In fact, this kind of power is generated every day on Earth by... lightning storms.

It may come as no surprise, therefore, that researchers at the University of St Andrews believe that signals that were received in 2009 from exoplanet HAT-P-11b might well have been caused by lightning storms on the distant planet. But what use is this, it doesn't represent extra-terrestrial intelligence, just extra-terrestrial weather (and we already know that even the other planets in our own solar system exhibit different weather characteristics).

alien lightning 1The point, if there is one, is that if we could modulate lightening storms, or perhaps induce them in a way that allowed them to occur in a predictable fashion, we could make signals big enough to be transmitted across inter-stellar space. According to Climate Viewer:
DARPA wants to trigger lightning to protect infrastructure, satellites, and use the artificially generated ELF waves to send messages worldwide. Lightning strikes are “triggered” at the University of Florida and University of Arizona, a network of sensors called the Holographic Array for Ionospheric Lightning (HAIL) collects info on these strikes, and HAARP has a large role in the whole process.

But if lightning can be heard many light years away, perhaps these artificially induced lightning strikes are nothing to do with their stated objective but are actually to 'send messages extra-terrestrially'. Maybe the signals received from HAT-P-11b are not just random lightning storms and despite the Daily Mail claiming that these are not messages from space, perhaps they are an attempt at communication after all. After all, stranger things have been true!

haarp antenna array
add comment ( 173 views )   |  0 trackbacks   |  permalink   |   ( 3 / 1398 )


<<First <Back | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | Next> Last>>