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FCC to fight wireless devices that receive signals from the wrong frequencies

The Federal Communications Commission unanimously voted to launch an inquiry into poorly designed wireless devices that receive transmissions from outside their allotted frequencies. The Notice of Inquiry (NOI) approved Thursday could result in new receiver regulations and is the first major step in the FCC's quest to prevent future conflicts like the high-profile battle between the aviation and cellular industries, in which a 5G rollout was delayed because airplane altimeters receive… ( More...

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Kenneth Crips 12
This is cute. Talk about closing the gate after the horse was let out. The ground radars on Commercial airlines were designed to FCC specs when first approved by the FCC, and FAA. Now you are letting the wireless industry off the hook for your stupid decisions.
Remember to inform the Chinese manufacturers of the final outcome.
sparkie624 3
That is going to be an interesting battle! Will be interesting to see exactly what they do with it.
Seems to me that the plain meaning of the quoted language establishing FCC's regulatory authority only authorizes regulation of transmitters and does not permit the proposed foray into regulating receivers. That will be the position that the profit-over-safety folks will take, and they will be right. When the receiver is part of an altimeter, one would have thought market forces, if not ordinary corporate responsibility, would have kept unsafe products off the market. Since the feckless corporate class doesn't give a shit about safety (only the appearance of safety) we must rely on the feckless Congress to legislate (i.e: enact a law) conferring appropriate regulatory authority, perhaps narrowly limited to receivers used by aircraft, such as in altimeters. This is not rocket science. It's pretty straight forward. I do not understand why industry leadership would not advocate for this kind of regulation. After all, if every has to live with it, it doesn't put anyone at a competitive disadvantage.
I hope you're right, but I fear they will take steps. Most consumer receivers have an FCC Type Acceptance certificate that specifically states it will accept any interference and will not cause harmful interference. Ham radio has to solve any interference it creates out of its bands. Aviation equipment used in navigation has an FAA TSO number certifying it meets technical standards. But, as has been made clear by the recent AD, the FAA can change its mind pretty much when it wants to as to compliance. You are right the phone companies don't care, unless someone starts transmitting on their guard bands and then the FCC will DF the signal and cart the broadcaster away.
Sorak 1
This is Part 15. What I don't understand is why all devices don't have to be Part 15 compliant not just the one operating in what are technically so called unlicensed spaces.
wtwisniewski 2
Part of the problem is that the FAA and ICAO operate with a "live in the past" mindset when it comes to electronic technology. Businesses like 5G telecoms use the latest. Even hollywood predicted most of today's radio gadgets, but aviation refused to look ahead. Manufacturers don't warrant nor expect their gear to be used as long as actually is and in the past there was little C band interference to worry about.I suppose the FCC was acting in concordance with FAA's system outlooks and culture. Examples: COM is 1930s voice technology, mode C, S, and ADSB haven't advanced the radio signalling past 1950s IFF technology. To be fair, GPS/WAAS is modern as is UAT.

We went through this with Harbin's LightSquared when the FCC sold the GPS guardband frequency at auction cheaply to Lightsquared. The physics of radio signal generation and transmission require spacing between frequencies. That's why the original FCC, charged with administering the spectrum before it became an Obama/Biden profit center, placed the guardbands and strictly limited radiated power in these guardbands. The GPS fiasco we dodged is exactly the same situation. The FCC was prepared to let Lightsquared put ground stations blasting away, equivalent to having your teen age kid's stereo at full volume next to your closed bedroom door while you're having a quiet conversation. To make those two uses compatible, you'd have to build a soundproof wall and door as thick as a bank vault.

The only reason the FCC and Lightsquared (who contributed heavily to Obama/Biden campaigns) got stopped was the Military, Airlines, General Aviation, State Highway Departments, Garmin, John Deere and the agriculture lobby who depended on receiving very faint GPS signals accurately to plant crops, navigate aircraft, ships and cars, survey land, etc, came together to oppose this.

The present fiasco only affects a certain safety segment of aviation and not nearly everyone in the country.

Bandpass filters in those frequency ranges are large and bulky and there isn't room in aircraft for them. This will require a redesign of the whole radio altimeter system, or we can tell the cellular people they have to pay for the ground and aircraft equipment they need to replace, and compensate the operators for the downtime.

The FCC needs to get out of the business of making money by ill advised sales of radio spectrum and back in the business of making sound technical decisions and coordination of users on the frequencies before they permit incompatible uses of adjacent spectrum.
I just received a news release. It seems I was wrong about Lightsquared and the threat to GPS. Lightsquared went bankrupt. Its remains became Ligado Networks and the new improved FCC granted them a Redo. This is after a low powered test of the Lightsquared plan in the Nevada desert disrupted GPS for 1000 miles at the flight levels from a single station running at reduced power in the L-band GPS guard band.

On April 25, a collection of GPS users, aviation groups, agriculture groups, nearly every important GPS user group in the country just wrote a letter to the Congressional Leadership prostesting the FCC's decision to reverse its decision from a decade ago asking for a Stay of the newest FCC order allowing Ligado to proceed with the original disruptive implementation plan as early as September 2022.

I was criticized for keeping an ADF and a VHF ILS system in the aircraft as backup to GPS navigation. I'm keeping the stuff in the airplane until sanity returns to our government. I will not hold my breath.
Chuck Wain 3
I disagree with your analysis. Bandpass filters in this frequency range are small, think millimeters, at 4.2 to 4.4GHZ. When the altimeters were originally designed, a long time ago the spectrum in this frequency range was not being used very heavily. My thought is that the engineers doing the design were not concerned with keeping the pass band tight. They got away with it because no one challenged them. Times change, now the GHz bands are being used extensively, for example your 5G WiFi is at 5Ghz. I suggest that part of the problem is the antiquated way the FAA does certifications. Once a part is certified the manufacturer has no incentive to makes updates, since that requires a time consuming and expensive re-certification. There is only so much spectrum available. We need to be able to make efficient use of it with up to date design methodology.
Sorak 1
I agree. All receiver portions need to be treated with part 15 type rules which mitigate interference. It should follow that certification includes a devices ability to ignore interference from outside its own operating band.
Gary Eldridge 3
This is a slippery slope! The FCC has already outstepped the bounds of it's jurisdiction. They have been auctioning off frequencies (that IT DOES NOT OWN) to the land mobile industry and made many millions of dollars. Now that they have sold off the frequencies right next to the radar altimeter band they want to impose more regulations to try to fix their mistake. When restrictions are imposed upon receivers how far will this go? It could go much farther than just tightening up the receiver specs but could go to restricting what frequencies a receiver is capable of receiving. They already once imposed an unconstitutional restriction on receivers back in the 80's to block the cellular band from receivers. What's next?
strickerje 1
I tend to agree; if this is an issue with the instruments, isn't their certification the FAA's jurisdiction?
Sorak 1
What I don't understand is why band specific receivers don't have the same restrictions as enforced by Part 15. Which is that receivers have to ignore signals from out of band. I don't think we need new laws, we just need to enforce the ones already on the books.
wtwisniewski 1
I hope the FCC will also scrutinize out of band emissions of the 5G radios, both the base stations/towers, and the consumer client devices - That's billions of radios that can wreak havoc and disable or confuse avionics.
Sorak 1
Why not require all device manufacturers to take steps on reducing out of band reception if that will cause failure of the device? We require the transmission to be on frequency. Why not say receivers need to be on frequency if it will cause themselves interference.
Ed Chapman 1
It’s about time.
R C 0
Standby for the wave of opinions informing us that the the private sector is always the place to go for solutions- the same private sector that created the problem …
Marc Rodstein 8
It wasn’t the private sector who created this problem. It was the government agencies who were derelict in their duty to prevent this.
srobak 4
Nothing takes to the airwaves without the FCC's approval. No matter who created the device - or the problem - the FCC gets the final say on if it is allowed to operate as a radio device. Just like the FAA with aircraft - and even again for aviation related radio devices. The Fed had ample opportunity to test, certify and approve or disapprove the devices - and bounce it back to the manufacturer with a list of deficiencies against attaining approval.
wtwisniewski 2
So, why don't they?
(Rhetorical question.)
Sorak 1
Because no one was whining about problems from neirby bands.


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