Simon Baker (Program Director)

The mobile world is pushing hard in the US, and potentially globally, to take spectrum from the satellite industry, which is under pressure as linear TV gives way to video streaming.

The mobile industry, with its massive data growth rates, is hungry for more and more of the radio spectrum.

5G is a bit of a bandwidth land grab, and has already hoovered up sections of what was left in the middle bands and then at the less occupied top of the spectrum.

It has been pretty usual in the allocation of frequency for new cellular generations to get two separate blocks of frequency, but 5G has mid bands (sub-6GHz) and then a big gap to the mm wave. The mm wave demands network towers much closer together. Most countries are not even thinking about using it yet.

So it is not surprising that attempts are being made to make some more spectrum available lower down the bands in the sub-6GHz zones.

Satellite Operators Saw Big Bucks in Selling Off C-Band

Nor is it a surprise that such initiatives are most advanced in the US, where 5G mid-band frequency is currently in short supply — operator Verizon has very little, needing to move straight to mm wave for much of its deployment.

An initial target for more frequency is the satellite TV industry, which is taking a hit as viewing patterns change and “cord-cutting” becomes prevalent in the US — the satellites feed the cable networks.

Their worlds were formerly very separate. The mobile industry used completely different terms for the initial frequency band which it is now trying to prise from the satellite community — what the satellite folks call “C-Band”, focused on 3.7 to 4.2GHz for the downlink signals and between 5.925 to 6.425GHz for the signals sent up to the satellites.

Just like mobile, satellite usage has been moving up the spectrum to find more bandwidth as technology has advanced. In the US, C-Band could be fairly easily swapped out for satellites for higher frequency, albeit with new antennas and reception electronics and some new satellites launched.

A grouping of satellite operators had hoped to do a private deal with US mobile networks for handing over 300MHz of C-Band for a cool sum estimated by analysts at $30 billion and up. In November, however, the Federal Communications Commission decided that it should run the reallocation of frequency itself (with most of the money presumably going to the US government, rather than companies outside the US — the key satellite players involved, SES and Intelsat, are based in Luxembourg).

Spectrum as a Fungible Investment

C-Band is not used for satellite TV broadcasting in Europe. It has, however, advantages in countries with heavy rainfall, which can degrade satellite signal quality, and so is employed for instance in parts of Southeast Asia and in Africa.

In Africa there is not much current pressure on frequency use for mobile, but in Southeast Asia there is, with the GSMA, which represents the interests of mobile operators, pushing for C-Band reuse for 5G in the 3.3–3.8GHz band.

5G Free Satellite

From C-Band to Ku-Band

In the US spectrum is considered an asset class much more than in other parts of the world. Serious discussion is brewing there of freeing up some of the next satellite band up, the “Ku-Band” to the satellite crowd, which lies in the 12–18GHz range.

Though they would involve smaller service areas from a cellular tower than C-Band, such signals would provide much more extensive coverage from a single point than mm wave.

One person who potentially could benefit from any move here is Michael Dell, founder of the eponymous PC maker, who has Ku-Band holdings in the US. This autumn he called for that spectrum to be made available to 5G, according to Light Reading.

Michael Dell: Not just PCs — he has investments in US Ku-Band spectrum

Internationally, moves on switching Ku-Band satellite use to 5G will be much more problematic than on C-Band. Ku-Band is the bread and butter of the direct to home satellite TV industry in many regions, including the Americas and Europe.

In addition, there are other new contenders in the satellite business for its use — Elon Musk’s Starlink and the OneWeb low earth orbit satellite constellations both plan to operate in this band.

Planning for Even Higher Frequencies

TV and telecommunications satellites use a third frequency allocation, the “Ka-Band” (26.5–40GHz), which is yet higher up the spectrum with wavelengths from slightly over 1cm to 7.5cm.

This is about as high up the spectrum telecom and TV satellite signals can be received easily, and so may become the satellite industry’s last bastion. A third contender in low earth orbit satellite systems, Jeff Bezos’ Kuiper constellation, aims to work in this band.

Individual countries have discretion to alter frequency use within their territories, but the general bands are set globally or regionally by meetings of the Radiocommunication Assembly, an offshoot of the International Telecommunications Union (ITU), itself part of the United Nations. Its decision-making process may appear rather byzantine, and its spectrum get togethers infrequent, but the outcomes can be very important.

The latest sessions, known as the WRC — World Radio Conference, were held in Sharm El Sheikh in November. With a lot of lobbying from the GSMA, more frequency was set aside for 5G in the 40GHz and 66GHz ranges, well up in the mm wave, but also at the lower 26GHz. The next important round for 5G will be the next WRC in 2023.

Lower Bands May Also Become Available

The last area to look in the search for 5G bandwidth is away from satellites, at changes lower down the spectrum. Such refarming of frequencies has been common in the past.

Some low-band frequency has been allocated to 5G at 600MHz, which T-Mobile is already bringing into use in the US.

Mobile operators also have their eyes on the 700MHz band in what is known as the “digital dividend”, spectrum which has become or may become free from country to country as analogue TV signals are switched off following the move to digital multiplexes. Simple things first.

 

 

If you want to learn more about this topic or have any questions, please contact Simon Baker, or head over to https://uk.idc.com and drop your details in the form on the top right.

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