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http://insidegnss.com/node/4608
As GAvin as posted before, it seems the airways are getting very crowded. I suspect that if GNSS was still only the domain of surveying that we would have lost a long time ago. The request is for a good cause and my limitied knowledge of frequencies and fluids allows me to understand why the device won't work at higher frequencies, but it shows how much pressure there is on frequencies in general.
I can see this device creating a few localized cases of interference. But on the good side it is low power, directed into the patient, not used for communications, and will not be super-numerous. I didn't see anything stating the power, but I'd hope that it wasn't more than a fraction of a watt for a short time, or else it could cause some problems for the patient.