White Space competitors fight dirty Microsoft and Spectrum Bridge, both competing to provide databases of available White Space radio frequencies, stand accused of demonstrating surprising incompetence in managing their own meagre spectrum use. Filings with the FCC argue that neither Microsoft nor Spectrum Bridge should be allowed to run White Space databases, …
BBC London's frequency would contain the "I'm here signal", still decodable in Birmingham. Which is exactly where & how the whitefi (!?) products would be operating, but now they can't because of the signal. Making the whole thing impossible.
See, maybe a few engineers have thought longer on this than you.
For a second, that will completely screw up the intended transmission modulation of the "I am here" beacon
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For thirds, televisions are supposed to be receive only. If they tried to transmit an "I am here" on the frequency they were listening to, what do you think would happen to what they were receiving? not to mention a significant part-number increase for the transmitter...
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Fourth and finally, there are an absolutely huge number of places where if the TV multiplex transmitter were sending the "I am here" (hint, it is ALREADY sending a known modulation pattern, you'd think that would be enough?), it would be exactly as receivable to the white-fi unit as the TV signal, that the houses are using a nice, big, high-gain antenna to receive. Chances are that the little omni stick used by the white-fi would never hear the TV signal. But would be more powerful locally than the TV signal.
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Oops.
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Detect and avoid provably does not work. Databases are the fall-back position (and there are examples where they won't work even when competently implemented) and depend on the competence of the administrators.
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Mine is the one with the little SDR receiver in the pocket.
If you've got multiple databases then one or more is likely to be out of date so just how long will it take them to knock out ITV in one or more regions? Hopefully the UK will have one database, then there's only one useless organisation to complain to (and wait 2 weeks for anything to be done).
The problem isn't the databases, its persuading people to use them. What about touring groups, will they remember to look up & reset their systems for every performance? Or a static bit of equipment that gets used for years, and then one day you move house & forget that it needs to be changed, or have lost the instruction book, or...
Disaster waiting to happen.
The problem is that they will probably say the equipment has to automatically locate itself by pinging something on the internet which will geolocate it from IP address.
That's great, except that when I am in the UK, my IP address is for Madrid. When I am in Madrid, depending on the wind direction and other such things, my IP address is Madrid, Docklands, or Portsmouth!!
Also in Madrid, the town 8km from me uses different frequencies, and the main transmitter for most of the city uses yet still different ones. If you consider the whole Madrid area in total, there probably isn't much whitespace with all the fill-in transmitters to overcome the hills and moutains. Meanwhile, the IP addresses don't resolve to anywhere near that level of accuracy because the IP address pool seems to be shared across the whole area.
"There is nothing wrong with your television set. Do not attempt to adjust the picture. We are controlling transmission. If we wish to make it louder, we will bring up the volume. If we wish to make it softer, we will tune it to a whisper. We will control the horizontal. We will control the vertical. We can roll the image, make it flutter. We can change the focus to a soft blur or sharpen it to crystal clarity. For the next hour, sit quietly and we will control all that you see and hear. We repeat: there is nothing wrong with your television set. You are about to participate in a great adventure. You are about to experience the awe and mystery which reaches from the inner mind to..."
our propaganda machine?
the pockets of our shareholders?
the delivery of our software?
our control of the airwaves?
all of the above?
"Both complaints conclude that any company unable to follow the rules can't be trusted to hold the data on which everyone else will rely to avoid similar infractions, and they may have a point".
Not really. It's like saying a bank manager who loses their wallet shouldn't be trusted to run a bank, or that if a standards body fails to follow its own standards it cannot be allowed to define standards.
The fact is the "building and provision of database" and "using and abiding" by it are separate functions which have no true bearing on each other.
Potentially taking out TV service in a large U.S. city is not a trivial infraction, and if MS had really messed up they might have done more than take the latest reality show off the air.
I have no real love for the bit telcos, but they do know how to manage spectrum.
an old wired network protocol parody that included:
If a collision occurs, double the voltage and resend the packet.
Perhaps a similar protocol could be implemented for White Space:
If interference is detected, double the transmission power and resend.
The access point with it's own power station wins!
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