{"id":77853,"date":"2026-04-03T14:40:17","date_gmt":"2026-04-03T12:40:17","guid":{"rendered":"https:\/\/www.iemn.fr\/?p=77853"},"modified":"2026-04-03T14:45:40","modified_gmt":"2026-04-03T12:45:40","slug":"seminaire-martine-lienard-7_04_2026-seminaire-de-vulgarisation-scientifique","status":"publish","type":"post","link":"https:\/\/www.iemn.fr\/en\/a-la-une\/seminaire-martine-lienard-7_04_2026-seminaire-de-vulgarisation-scientifique.html","title":{"rendered":"S\u00e9minaire : Martine LIENARD 7_04_2026 – S\u00e9minaire de vulgarisation scientifique"},"content":{"rendered":"

SEMINAIRE<\/span><\/h2>\n
\n

<\/h3>\n<\/div><\/section>
\n

Martine LENARD<\/h4>\n

Les \u00ab\u00a0myst\u00e8res\u00a0\u00bb de la propagation en tunnel<\/b><\/h4>\n<\/div><\/section>
\n

Mardi 7 avril 2026
\nde 12h15 \u00e0 12h45
\nEspace \u00e9v\u00e9nementiel de Lilliad
\nCampus Cit\u00e9 scientifique
\nPr Martine Lienard IEMN<\/span><\/span><\/strong><\/p>\n

\"\"<\/a>Dans un monde o\u00f9 la connectivit\u00e9 doit \u00eatre partout, m\u00eame sous terre, les tunnels ferroviaires et routiers posent un d\u00e9fi unique : comment assurer des communications fiables dans un environnement confin\u00e9 et complexe ?
\nCette pr\u00e9sentation explore d\u2019abord les besoins croissants en connectivit\u00e9 dans les tunnels, avant de poser les bases de la propagation des ondes. On y d\u00e9couvre pourquoi le signal peut fluctuer (\u00e9vanouissements) et comment la g\u00e9om\u00e9trie du tunnel rectiligne, courbe ou pr\u00e9sence de r\u00e9tr\u00e9cissements influence directement la distance couverte par un \u00e9metteur. Ces \u00e9l\u00e9ments permettent ensuite de comprendre les choix d\u2019ing\u00e9nierie n\u00e9cessaires pour d\u00e9ployer efficacement des antennes, illustr\u00e9s par un cas concret en tunnel de m\u00e9tro.
\nLa question cl\u00e9 est ensuite pos\u00e9e : la 5G peut-elle r\u00e9ellement apporter du tr\u00e8s haut d\u00e9bit en tunnel ? En milieu urbain, et sous certaines conditions, elle promet des gains importants en d\u00e9bit par rapport \u00e0 la 4G. Mais que deviennent ces gains en environnement confin\u00e9 ?
\nEnfin, la pr\u00e9sentation s\u2019ouvre sur les enjeux futurs : accompagner l\u2019arriv\u00e9e des v\u00e9hicules autonomes, avec des exigences accrues en termes de continuit\u00e9 de service, de robustesse et de performance.<\/p>\n<\/div><\/section><\/p><\/div>","protected":false},"excerpt":{"rendered":"","protected":false},"author":20,"featured_media":73855,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,313],"tags":[],"class_list":["post-77853","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-a-la-une","category-accueil-etudiants"],"_links":{"self":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/77853","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/users\/20"}],"replies":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/comments?post=77853"}],"version-history":[{"count":9,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/77853\/revisions"}],"predecessor-version":[{"id":77858,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/77853\/revisions\/77858"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media\/73855"}],"wp:attachment":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media?parent=77853"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/categories?post=77853"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/tags?post=77853"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}