5G Hubris | Learning by Proxy

The FAA is left to clean up the mess that the Trump administration created.

At the fag of the 19th century, Mr Marconi discovered that we could send voice over radio waves. Since then we have learnt to exploit the entire spectrum for one thing or the other. The waves that he used were low frequency and therefore he could only transmit sound.

At around the same time, Dr J.C. Bose started researching transmission over millimetre waves, which were high-frequency waves. It is this technology that makes most of the modern cellular communication possible.

Source GSMA

A frequency of 1 Hz implies a wave per second; a kilohertz is a thousand waves per second; a megahertz is a million waves per second and a gigahertz is a billion waves a second. If you were to suppose that each wave carried a bit, you would be able to see how higher frequency waves would be able to deliver higher data speeds.

Lower frequency waves tend to penetrate buildings better, so you can listen to the radio even if you are sitting in your basement. But they have a lesser capacity to carry data as fewer waves are available. High-frequency waves tend to have poorer penetration, they bounce off buildings but have a higher capacity to carry information.

Unfortunately, the same bands must be shared with the military, the aviation industry, the broadcasting industry, GPS, Weather radar, satellite communication and the telecom industry.

Various governments and standards agencies, therefore, work together to outline the parts of the spectrum that can be used for various activities.

Mobile Technolo-G

1G - Was a single band network that operated at 800MHz or 900Mhz. This was created in 1973 and was only good to carry voice.

2G - moved into dual-band and operated in the 800 MHz, 1800MHz, 900 MHz and 1900 MHz. The first use of data on these networks allowed the creation of the Short Messaging Service (SMS). Then the higher frequency band was used to transfer data through the General Packet Radio Service (GPRS) which could transfer data at 114Kbps and was known as 2.5G.

3G - moved to operate in the 800 MHz, 850 MHz, 900 Mhz, 1700 Mhz, 1900 MHz and 2100 MHz. With higher frequencies and multiple bands, it became possible to allow separate voice and data sessions to be carried across different frequencies. Also, the development of the High-Speed Packet Access sped up data speeds.

4G - was not about the spectrum as much as it was about increasing the efficiency with which that spectrum was harnessed. This is why it is called Long Term Evolution (LTE). The network itself was upgraded based on Internet Protocol. A technology called Orthogonal Frequency Division Multiplexing (OFDM) made spectrum utilisation far more efficient.

5G - Operates with many of the same technologies used in 4G. But where 3G had reached up to 2.1 GHz, this additionally used spectrum in the 3 GHz - 4GHz band.

Mobile phone companies in the United States are rolling out 5G service in a spectrum of radio waves with frequencies between 3.7 and 3.98 GHz. The companies paid the US government $81 billion in 2021 for the right to use those frequencies, known as the C-Band. But in Europe, 5G services use the slower 3.4 to 3.8 GHz range of spectrum.

The aviation industry is worried that US 5G service is too close to the spectrum used by radar altimeters, which is between 4.2 and 4.4 GHz. Europe does not face the same risk, according to the industry, because there is a much larger buffer between the spectrum used by radar altimeters and 5G.

Source: CNN

The higher the frequency, the faster the data transfer can be. American service providers in their hubris strayed upstream and ended up with a spectrum block that is very close to the range at which the radio altimeters in planes operate.

Now, a few things about the FAA. The FAA was created through the Federal Aviation Act in the 1950s after a spate of accidents that involves mid-air collisions over the Grand Canyon. While they had to regulate civil aviation, they were also tasked with aviation safety. They created the National Transportation Safety Board and took all of the safety-related issues under their wings.

The work that the FAA has done over the second half of the 20th century has made air travel safe not just in the US but all over the world. Their work has led to phenomenal changes in the design and construction of planes. Since US is the largest aviation market, almost all plane manufacturers use their guidelines.

Because of their work, the odds of riding a cycle and dying, are greater than the odds of getting killed flying in a plane. So what they say cannot be taken lightly.

The Federal Aviation Administration (FAA) has warned that potential interference could affect sensitive airplane instruments such as altimeters and significantly hamper low-visibility operations.

"This means that on a day like yesterday, more than 1,100 flights and 100,000 passengers would be subjected to cancellations, diversions or delays," the letter cautioned.

[...]

"With the proposed restrictions at selected airports, the transportation industry is preparing for some service disruption. We are optimistic that we can work across industries and with government to finalize solutions that safely mitigate as many schedule impacts as possible," plane maker Boeing (BA.N) said on Monday.

Source: Reuters

Add to this, the American idiosyncracies.

As wireless carriers are fond of pointing out, 40 other countries have already rolled out some version of C-band 5G networks without causing chaos at airports. But the FAA argues that US 5G networks pose extra challenges to flight safety because of their unique design:

Stronger signals. In order to extend their range, particularly in rural areas, US 5G towers are allowed to broadcast wireless signals 2.5 times more powerful than French 5G towers.

Antenna angles. Unlike other countries, the US does not require wireless carriers to angle their 5G antennas down toward the ground to reduce interference with airplanes.

Higher frequencies. The US will eventually allow wireless carriers to use frequencies as high as 3.98 gigahertz for 5G, which makes the American 5G band closer to the frequency range used by airplane altimeters (4.2-4.4 GHz).

Smaller airport buffers. US 5G buffer zones protect airplanes from signal interference for the final 20 seconds of flight before a plane reaches the runway. French 5G buffer zones, by comparison, protect planes for the final 96 seconds.

Source: Quartz

The American telecom providers have paid $81 billion to buy the 5G spectrum and then spent several billion dollars to upgrade their infrastructure to deliver 5G services. Then they had to deal with the delays and disruptions that were caused by COVID lockdowns and then due to the shortfall in chip manufacturing.

It is time for them to milk this cow and they are paying interest every day. This delay will cost them dearly - actually not that much, given how low, interest rates are right now - but it will cost them some.

When the 5G auction took place in the US, the Trump administration was still in place. An absolute lunatic was running the FCC. Lobbying is just another form of corruption. There was no shortage of corruption in the Trump administration. Hubris trampled sensibility and this problem exists.

The telecom companies have spent hundreds of Billions and would not be in a position to afford changes now. The FAA will have to find a solution.