{"id":48737,"date":"2021-12-07T10:16:47","date_gmt":"2021-12-07T08:16:47","guid":{"rendered":"https:\/\/www.iemn.fr\/articles-temporaires-anglais\/et-si-le-monde-de-linternet-des-objets-netait-pas-gaussien-2.html"},"modified":"2022-01-06T11:08:05","modified_gmt":"2022-01-06T09:08:05","slug":"et-si-le-monde-de-linternet-des-objets-netait-pas-gaussien-2","status":"publish","type":"post","link":"https:\/\/www.iemn.fr\/en\/newsletter\/et-si-le-monde-de-linternet-des-objets-netait-pas-gaussien-2.html","title":{"rendered":"What if the world of the Internet of Things wasn\u2019t Gaussian?"},"content":{"rendered":"<section  class='av_textblock_section av-sd1awe-f0f0f8bddb5e35c481ad2a58a07ba29f'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><h2 style=\"text-align: center;\"><span style=\"color: #00c3ff;\">What if the world of the Internet of Things wasn\u2019t Gaussian?<\/span><\/h2>\n<p><strong>\u00a0<\/strong><\/p>\n<\/div><\/section>\n<section  class='av_textblock_section av-kwvu12lw-69226bb7cc7e172b098fd0f2830cc552'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><p><a href=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-48721 size-full\" src=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet.jpg\" alt=\"\" width=\"600\" height=\"180\" srcset=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet.jpg 600w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet-300x90.jpg 300w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet-18x5.jpg 18w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/a><\/p>\n<\/div><\/section>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-1ap6qge-58e72f37fe3342ccf59e7ab3842694f5\">\n.flex_column.av-1ap6qge-58e72f37fe3342ccf59e7ab3842694f5{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-1ap6qge-58e72f37fe3342ccf59e7ab3842694f5 av_one_full  avia-builder-el-2  el_after_av_textblock  el_before_av_one_half  first flex_column_div av-zero-column-padding  column-top-margin'     ><section  class='av_textblock_section av-sd1awe-f0f0f8bddb5e35c481ad2a58a07ba29f'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><blockquote>\n<p><strong><a href=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet4.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft wp-image-48725 size-medium\" src=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet4-300x152.jpg\" alt=\"\" width=\"300\" height=\"152\" srcset=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet4-300x152.jpg 300w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet4-18x9.jpg 18w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet4.jpg 461w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a>Interference is constantly growing in wireless communications due to the increase of communicating objects. It comes in addition to the usual receiver noise. However, it does not have the same statistical properties which should significantly impact the design of the receiver. Realized with researchers from Aalborg, the first measurements of these interferences in the 868 MHz band highlight their non-Gaussian nature.<br \/>\n5G and beyond sees an ever-increasing density of connected things. As not all devices are coordinated, there are limited opportunities to mitigate interference. As such, it is crucial to characterize the interference in order to understand its impact on coding, waveform and receiver design. While a number of theoretical models have been developed, there is very little experimental validation. This work addresses this key gap in understanding by performing statistical analysis on recent measurements in the unlicensed 863 - 870 MHz band in different regions of Aalborg, Denmark (see Figure). In particular, the measurement data show that the distribution of the interference power is heavy tailed, confirming predictions from theoretical models.<br \/>\n<\/strong><\/p>\n<\/blockquote>\n<\/div><\/section><\/div>\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-10qnhym-a073ff588b5c09cd8249c5cdf6e2b42b\">\n.flex_column.av-10qnhym-a073ff588b5c09cd8249c5cdf6e2b42b{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-10qnhym-a073ff588b5c09cd8249c5cdf6e2b42b av_one_half  avia-builder-el-4  el_after_av_one_full  el_before_av_one_half  first flex_column_div av-zero-column-padding  column-top-margin'     ><section  class='av_textblock_section av-kwvukgz1-a42259eb8fabdae76f908f76c9dd3616'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><p>1.     Interference is the consequence of concurrent, at least partially, transmissions from different devices on the same channel observed by a given receiver. Dating back to Middleton (1977), stochastic geometry has played an important role in characterizing interference statistics. In this approach, interferers are located according to a homogeneous Poisson point process, and non-Gaussian interference distributions naturally arise. A significant result is that the tail behaviour of the distribution is dominated by the strongest interferer and sub-exponential distributions often arise.<\/p>\n<p>2.     This work presents the first confrontation of these theoretical results to experimental data. Received power measurements were performed at 5 distinct locations in Aalborg (Denmark) - downtown, business park, hospital, industrial area and residential area. Measurements were performed at street level by using a radio network scanner equipped with an omni-directional antenna for a period of 2 hours. The entire on-air RF activity in the 868 MHz ISM band (863-870 MHz) was recorded.<\/p>\n<p><a href=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet3.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-48726 alignnone\" src=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet3-300x189.jpg\" alt=\"\" width=\"300\" height=\"189\" srcset=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet3-300x189.jpg 300w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet3-18x12.jpg 18w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2021\/12\/visuel_internet_objet3.jpg 457w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<\/div><\/section><\/div><\/p>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-oidg3y-80faa2204b71608d201bc6c1f3e984ff\">\n.flex_column.av-oidg3y-80faa2204b71608d201bc6c1f3e984ff{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-oidg3y-80faa2204b71608d201bc6c1f3e984ff av_one_half  avia-builder-el-6  el_after_av_one_half  avia-builder-el-last  flex_column_div av-zero-column-padding  column-top-margin'     ><section  class='av_textblock_section av-kwvukgz1-a42259eb8fabdae76f908f76c9dd3616'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><p>3.     The measurement data obtained at the five different locations, confirm the hypothesis of the sub-exponential nature of the distribution of interference power. The presented graph shows the survival function of the data and from known distribution (exponential, denoted by a=2, and sub-exponential, denoted by a=1.4, 1.6 and 1.8). It clearly validates the heavy tailed nature of the interference in the context of Internet of Things (IoT) communications. Interference models are the key to designing efficient coding and decoding strategies as well as efficiently adapting channel access and the network topology. As such, the measurement data suggests that there is a need to reconsider the utility of Gaussian models in network design for the IoT.<\/p>\n<p><em>\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-riqc6r-2d9a6f78f8ab5c7b5c41eee4f1ead829\">\n.av_font_icon.av-riqc6r-2d9a6f78f8ab5c7b5c41eee4f1ead829 .av-icon-char{\nfont-size:25px;\nline-height:25px;\n}\n<\/style>\n<span  class='av_font_icon av-riqc6r-2d9a6f78f8ab5c7b5c41eee4f1ead829 avia_animate_when_visible av-icon-style- avia-icon-pos-left av-no-color avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue80c' data-av_iconfont='entypo-fontello' ><\/span><\/span>Laurent Clavier, Troels Pedersen, Ignacio Larrad, Mads Lauridsen, and Malcolm Egan, Experimental Evidence for Heavy Tailed Interference in the IoT, IEEE COMMUNICATIONS<\/em><br \/>\n<em>LETTERS 25 (2021), no. 3, 692-695.<\/em><\/p>\n<div  class='avia-button-wrap av-rpqvoq-9fbcd0a22523d73ab78dafd20c74da17-wrap avia-button-left  avia-builder-el-9  el_after_av_font_icon  avia-builder-el-last'><a href='mailto:laurent.clavier@univ-lille.fr'  class='avia-button av-rpqvoq-9fbcd0a22523d73ab78dafd20c74da17 av-link-btn avia-icon_select-yes-left-icon avia-size-small avia-position-left avia-color-silver'   aria-label=\"laurent.clavier@univ-lille.fr\"><span class='avia_button_icon avia_button_icon_left' aria-hidden='true' data-av_icon='\ue805' data-av_iconfont='entypo-fontello'><\/span><span class='avia_iconbox_title' >laurent.clavier@univ-lille.fr<\/span><\/a><\/div>\n<\/div><\/section><\/div>","protected":false},"excerpt":{"rendered":"","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[297],"tags":[],"class_list":["post-48737","post","type-post","status-publish","format-standard","hentry","category-newsletter"],"_links":{"self":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/48737","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\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/comments?post=48737"}],"version-history":[{"count":0,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/48737\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media?parent=48737"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/categories?post=48737"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/tags?post=48737"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}