6G promises to merge the human and digital worlds

While the deploy­ment of 5G is still in its infan­cy, research centres and ope­ra­tors are alrea­dy wor­king on 6G. This tech­no­lo­gy is expec­ted to be avai­lable around 2030. What will it be used for and what will the bene­fits be ? What chal­lenges will need to be addressed ?

5G net­work tech­no­lo­gy, known as mobile broad­band, was laun­ched in France in Novem­ber 2020. It is gra­dual­ly being rol­led out across the coun­try but will only be ful­ly deployed by 2030. At the end of Sep­tem­ber 2021, Arcep (the French regu­la­to­ry autho­ri­ty for elec­tro­nic com­mu­ni­ca­tions, posts, and press dis­tri­bu­tion) lis­ted some 22,600 anten­nas ins­tal­led by the four ope­ra­tors Bouygues Tele­com, Free Mobile, Orange and SFR. These sites trans­mit in the three 5G fre­quen­cy bands (700–800 MHz ; 1.8–2.1 GHz and 3.5 GHz). Motor­ways and main roads should be cove­red in 2025 and 2027 respectively.

Major mobile com­mu­ni­ca­tions equip­ment manu­fac­tu­rers and spe­cia­list research centres have not wai­ted to deve­lop next gene­ra­tion tech­no­lo­gies. If it takes a decade to ful­ly deploy a tech­no­lo­gy, it takes at least as long to deve­lop and stan­dar­dise it so that it is rea­dy for the mar­ket. This explains why R&D work on 6G star­ted before 5G was even launched.

In its three fre­quen­cy bands, the 5G mobile net­work alrea­dy offers speeds 10 times fas­ter than 4G. The 6G net­work is expec­ted to offer speeds 100 times higher than those of 5G, thanks to the use of tera­hertz waves. In fact, the fre­quen­cies allo­ca­ted to 6G are bet­ween 100 GHz and 30 THz.

Howe­ver, these very high fre­quen­cies pose some pro­blems research labo­ra­to­ries are cur­rent­ly trying to solve. In tele­com­mu­ni­ca­tions, the lower the fre­quen­cy the fur­ther it car­ries and the lower the through­put. A higher fre­quen­cy does not car­ry as far, but with a bet­ter band­width. The­re­fore, we need to find a way to boost power of 6G to improve its per­for­mance over dis­tance while main­tai­ning high bandwidth.

In sum­mer 2021, the South Korean com­pa­ny LG and the Ger­man research ins­ti­tute Fraun­ho­fer car­ried out a test and suc­cess­ful­ly trans­fer­red data over a dis­tance of 100 metres. The pre­vious test had been car­ried out a few weeks ear­lier by ano­ther Korean com­pa­ny, Sam­sung, over a dis­tance of ~15 metres.

Ano­ther dif­fi­cul­ty with very high fre­quen­cies is the loca­tion of the anten­nas. For the per­for­mance and speeds expec­ted from 6G to be achie­ved, the anten­nas must be spa­ced about 100 metres apart. While this does not pose a pro­blem of tech­ni­cal fea­si­bi­li­ty in urban areas – apart from public accep­ta­bi­li­ty – net­work cove­rage becomes more dif­fi­cult to ensure in rural areas. This is why ope­ra­tors are alrea­dy deve­lo­ping alter­na­tive solu­tions, in par­ti­cu­lar HAPS (High Alti­tude Plat­form Sta­tion). In Janua­ry 2022, Air­bus announ­ced that it was wor­king with NTT, DoCo­Mo and Sky to stu­dy the fea­si­bi­li­ty of satel­lite plat­forms that would pro­vide wire­less connec­ti­vi­ty ser­vices to areas poor­ly cove­red by mobile tech­no­lo­gies, such as the oceans, airs­pace, and areas that are iso­la­ted or hit by natu­ral disasters.

After voice (2G), text and SMS (3G), data and apps (4G), the Inter­net of Things and indus­trial auto­ma­tion (5G), 6G aims to open up a whole new field of appli­ca­tions. By inte­gra­ting the phy­si­cal and digi­tal worlds and com­bi­ning ima­ging, loca­tion and arti­fi­cial intel­li­gence, these appli­ca­tions will enable full immer­sion in digi­tal space for vir­tual rea­li­ty com­mu­ni­ca­tion, inter­ac­tion and col­la­bo­ra­tion expe­riences, as well as real-time tele-sur­ge­ry, 16K video strea­ming, auto­no­mous vehicles and digi­tal twins.

Accor­ding to Nokia, 6G will bene­fit from advances in six key tech­no­lo­gies. Advances in arti­fi­cial intel­li­gence and machine lear­ning (AI/ML) will improve com­mu­ni­ca­tion bet­ween two ter­mi­nals. Thanks to the tera­hertz fre­quen­cy spec­trum allo­ca­ted to it, 6G will offer speeds up to 100 times fas­ter than 5G. The net­work will be sen­si­tive to its envi­ron­ment, objects and people, which will allow it to locate and also mea­sure various para­me­ters (speed, tem­pe­ra­ture). The low laten­cy of 6G (micro­se­conds vs. mil­li­se­conds for 5G) will make reliable connec­ti­vi­ty pos­sible for real-time appli­ca­tions such as auto­no­mous vehicles or video confe­ren­cing. With this connec­ti­vi­ty, new net­work archi­tec­tures will replace wire­line net­works and faci­li­tate the deploy­ment of cus­to­mi­sed and auto­ma­ted net­works. Final­ly, 6G will be made with “secu­ri­ty by desi­gn” in mind, incor­po­ra­ting advan­ced secu­ri­ty fea­tures right from the start.

The tech­no­lo­gi­cal advances enabled by 6G will lead to dis­rup­tive inno­va­tion in seve­ral areas, inclu­ding auto­no­mous vehicles, indus­try 4.0 and tele­me­di­cine or health. This will trans­late into tan­gible eco­no­mic oppor­tu­ni­ties. In a recent sta­te­ment, the Lan­nion tech­no­lo­gy park (Brit­ta­ny) esti­mates that the rise of “5G could represent 20,000 new jobs and €15bn by 2025”. These figures sug­gest that 6G will have a signi­fi­cant impact.

Howe­ver, seve­ral chal­lenges remain. The issue of stan­dar­di­sing 6G tech­no­lo­gy on a glo­bal scale raises ques­tions of sove­rei­gn­ty and secu­ri­ty. In addi­tion, the issue of public accep­tance is like­ly to come up again, simi­lar to the debates on health risks and the real need for such tech­no­lo­gy that accom­pa­nied the launch of 5G.