5G Bandits Hijack GPS Frequencies - Granite Grok

5G Bandits Hijack GPS Frequencies

GPS Satellite

Steve asked me: “What’s up with 5G? Not the crazy health conspiracy theories – that’s just dumb, but I’m hearing of issues in relation to other communications bands. What’s the primary objection to it?” Well, Steve, as usual, had spotted a newsworthy item….

5G mast on fire
5G mast burns in the UK
As Steve said, the crazy health conspiracy stories are just that: 5G base stations are mostly made by Huawei, and they are accused of broadcasting the Chinese Coronavirus, or at least damaging our immune systems! As ridiculous as that is, conspiracy theorists in Europe, especially the UK, have been whipping up mobs to burn down 5G antenna masts, or in some cases, good old 4G/LTE masts, even disabling communications used by first responders. Hey, nobody said conspiracy theorists were smart!

Huawei phones home
Huawei phones home
Coronavirus aside, there are good reasons why we don’t want our 5G mobile infrastructure (next generation ultra-fast mobile internet) to be built by Huawei, prime amongst them that these base stations can be remotely managed, and our security agencies have excellent reasons to believe that data passing through them could be transferred to China. Apparently what’s good for the NSA to do, is not so good for the Chicom People’s Liberation Army to copy! (All of your bits are belong to us.)

That’s the Chicom connection dealt with, for now, so it’s time to look at the domestic communications company which is trying to bypass the rules to operate 5G communications on the cheap. Meet Ligado, formerly known as LightSquared, and before that, known as SkyTerra. They first came to our notice in 2012 as Obama cronies who even the Obama FCC would not license because their plans would render GPS useless for miles around each base station. Multiple government agencies, including the military, objected strenuously, and LightSquared did not get their license. Investors, who should have smelled a shady deal, lost bigly.

That was then, and this is now. The Trump Administration and FCC Chair, Ajit Pai, are deregulators at heart, and the renamed company, Ligado, risen (again) from bankruptcy, hired some big guns, including former Verizon CEO Ivan Seidenberg as Chairman of the Board, and Reed Hundt, former Clinton FCC Chairman and Obama advisor (just look at his book titles!), as a board member – who better to lobby even a Republican FCC, with some street cred, than those fine “upstanding” telecom experts, eh? Grok friend and contributor, Weegee alerted me to this scam arisen from its grave just before Steve asked me “What’s up with 5G?”

Ars Technica 5G graphic
Ars Technica 5G graphic: FCC approves ‘5G’ network despite military saying it will harm GPS

The basic problem is this: Ligado is not conventional 5G cellular communications, and they are not playing by the rules. Back in 2012, and again today, rather than compete for mobile telecommunications spectrum by bidding for it, or by suing the incumbents to level the playing field, like Microwave Communications Inc (MCI) did three decades ago when they broke the long distance telephone monopoly, SkyTerra/LightSquared/Ligado chose to cheat, to make an end run around the rules, to stake a claim to a frequency band reserved for space to ground communications, and specifically used for GPS and satellite telephony, knowing full well that their systems would render the current generation of GPS receivers useless. Nice guys!

Inverse Square Law
Wikipedia: Inverse Square Law
Spectrum plans for military, commercial, and amateur use always separate frequency bands used for local/broadcast/strong signals from those used for long distance transmission. In particular, bands used for transmission TO space and reception FROM space are kept well separated because after the long journey, the signals are weaker than anything you’d find on your short wave radio. This is due to something called the the “inverse square law” which states that a light, a sound, or a radio wave, gets weaker in proportion to the square of your distance from it.

Now, remember that Ligado plans to use channels cut from a roughly 100MHz slice of spectrum around 1.6GHz (1600MHz) which is EXCLUSIVELY for Space to Ground communication and is used by Inmarsat (satellite phones), GPS, and similar systems like the European Gallileo satellites. Other space-based transmitters in this band are no problem because their signals are greatly diminished by the journey, just like GPS signals are, and the GPS receivers have no trouble picking out the wanted signal from the band. BUT, current GPS receivers do not filter out signals within the Space to Ground band because they do not expect strong local signals within it. Indeed, the digital GPS receiver works best with minimal filtering.

CDMA type signal
CDMA signal and sidebands
When Ligado adds GROUND based transmitters, a deafening level of noise is added to the band which can disable GPS receivers a kilometer or more away (In their 2012 design, up to ten kilometers away!) Digital cellular signals are broad, and have significant noise “sidebands” which spill into adjacent channels, and reducing those sidebands to a negligible level requires very expensive filtering by the base station. (Would you trust cheapskates to do that?)

The collision course is simply this: GPS receivers are designed for maximum sensitivity to pick up the very weak satellite signals, and take advantage of the fact that (until now) there could not be powerful ground-based signals in the satellite band used for GPS. Ligado did not bid for 5G spectrum like other carriers, and now plans to transmit powerful, ground-based, signals in the satellite band used by GPS. Any current GPS receiver, including some used by the military and by civilian aircraft, cannot handle the Ligado base station transmissions without losing track of the satellites and giving you a “bum steer” as it were. The “compromise” under which the FCC was persuaded to allow Ligado’s operation uses lower transmitter power, and channels a little further spaced from GPS signals, but still WITHIN the space to ground exclusive band. (I keep using that word “exclusive,” but apparently it no longer means what I thought it meant!)

So, Steve, there is nothing wrong with, or unsafe about, 5G mobile networks as long as they are not made by Huawei, and they are using the agreed 5G frequency bands – they don’t interfere with GPS or other critical military or aviation technology. Ligado is something else, entirely, and is going to pose a major technical challenge for GPS in particular.

I close out with a thought I posed to my friend “Weegee” – “If I were a ChiCom plant, I couldn’t [mess] up US navigation and the military better than launching LightSquared/Ligado.” The answer? “YES”

Original Grok article on Skyterra/LightSquared
Ars Technica article on FCC approval of Ligado’s (slightly) less interfering plan
Ars Technica article on military objections to Ligado
Space News article on DoD’s new rebuke of FCC and the Ligado approval

This nugget from House Armed Services Committee Chairman Adam Smith (D-Wash.) via Space News:

“While the United States must be a leader in the implementation of 5G networks, our creation of these networks must not hamper our military’s operational capacity in any way,” said Smith. “China’s aggressive, global promotion of its 5G companies presents a considerable security challenge that must be addressed. However, Ligado’s proposal, which seeks a portion of spectrum adjacent to that used for Global Positioning Systems, poses an even larger security risk.”


WeegeeMany parts of this article based on a tip from, and discussions with “Weegee” An engineer and avid photographer who admires New York’s iconic crime photographer, Weegee, the author is an NH native, a conservative who believes that small government is the best government and the goverment’s proper role is that of referee rather than of playmaker as it is far too often today. And he believes in ‘bright line’ business regulations which are clear and unambiguous and not subject to ‘what’s the definition of is.’