The anechoic chamber: an experimental room for testing 5G networks and the IoT

With its two anechoic chambers, one of which, installed on the SophiaTech campus, is for measuring the performances of future 5G network antennas, Orange is at the forefront of research supporting the rise of new technologies and new uses.

With its two anechoic chambers, Orange is at the forefront of research supporting the rise of new technologies and new uses.

For two years now, Orange has had two anechoic chambers: one inaugurated on 3rd May 2016 at Orange Gardens, the Châtillon ecocampus dedicated to research and innovation, and the other on 4th November of the same year on the premises of the LEAT (Laboratory of electronics, antennas and telecommunications) on the SophiaTech campus within the framework of the CREMANT (Centre de REcherche Mutualisé sur les ANTennes: a shared laboratory between Orange Labs, the University of the Côte d’Azur, and the CNRS).

These enclosed metallic spaces, whose interior walls are covered with absorbent materials preventing reflection of electromagnetic waves, are designed on the one side to eliminate any external disturbance that could hinder measurements, and on the other to control emissions within the room over a very wide range of frequencies (30 MHz to over 100 GHz). The aim of these chambers is to measure performance of wireless communication systems, to study the risks of interference between technologies, and to measure electromagnetic compatibility of the cables.

A field of study and of measurement of antenna systems

The SophiaTech shared anechoic chamber has the particularity of being completely “deaf”. Aimed at measuring the performances of antennas for future 5G networks, the Internet of Things, or even vehicle-to-vehicle communications, providing the latter with the possibility to automatically exchange information amongst themselves, this 60 m² space accommodating antennas up to 2 m in diameter and 100 kg, enables testing in an environment that is devoid of all reflecting obstacles and interfering external signals.

The research projects carried out thanks to this facility are centred around three pillars:
● The exploration of new antenna technologies such as adaptive antennas for 5G networks, particularly for frequencies above 3 GHz, or even above 30 GHz, which, by combining a large number of antennas at transmission or at reception, enable for example an increase in the reach of mobile systems and their capacity to accommodate a larger number of users.
● The design of antennas and sensors for growth industries such as the Internet of Things, smart homes and cities, e-health, and connected autonomous vehicles.
● Software that enables modelling of the antennas so as to predict their radiation characteristics.

In order to improve the performance of this anechoic chamber, its functionalities have recently been extended. “This year the university project RANDOM@SophiaTech2.0 (a platform for the measurement of electromagnetic radiation of antennas and of diffraction up to millimetre waves of communication objects, sensors, and radar systems) financed the construction and commissioning of a compact base and of electronic equipment enabling measurement of radiation and diffraction of electromagnetic fields up to 260 GHz with a dynamic range of at least 70 dB” explains Éric Bonneau, Antennas Manager at Orange. With these extended functionalities, the project offers new possibilities for measuring active antennas (5G, backhaul…), “in far-field conditions between 3 and 200 GHz, so without resorting to tradition NF-FF (near-field-to-far-field) transformations, which require the knowledge of two field components in amplitude and phase”, specifies Éric Bonneau.

The chamber has thus become an essential tool for the characterisation of active antennas when a modulated signal is applied to them. “In order to be more agile in our experimental measurements, we made the choice to develop our own knowledge tools for these two test beds, based on the libraries of the chamber manufacturer for piloting the positioners, and on our own experience of microwave equipment control”, Éric Bonneau continues.

Measuring directive antennas in a limited space

One of the advantages of this anechoic chamber is that it is fitted with CATR (compact antenna test range) type equipment. This enables the generation, in a predefined zone of the anechoic chamber, of a quiet area (equiphase and equiamplitude, so as to recreate the far-field measurement conditions). The anechoic chamber can thus allow measurement of directional antennas at high or active frequencies (5G, backhaul…) in a limited space.

But this sophisticated and very high precision tool required special attention, in particular during its design: “The complexity of developing the chamber’s tool and the alignment of non-standard equipment coming from several providers, from across Europe and the United States, created a lot of logistical issues”, admits Éric Bonneau.

Orange’s investment in this type of tool highlights how essential research in this area is. In effect, although we may not always see them, antennas are all around us, in our computers, our mobile phones, etc. and they are now taking on new shapes, because the signals picked up are more and more subtle. Each communicating object of the future will no doubt have an antenna designed specifically for it. In this context, research, notably through anechoic chambers, is a requirement for supporting the rise of new technologies and new uses.

Read also on Hello Future

Traveling Safely in Increasingly Autonomous Driverless Cars

Discover

Standalone 5G: An Even More Adaptable Toolbox

Discover
Lights in an operating theater

Introducing 5G into the Operating Theater

Discover

With 5G, XR experiences increasingly inclusive and accessible to all

Discover
Live streaming has become increasingly widespread. With the addition of 5G, this service can be dramatically improved at all levels, including image quality, download times, interruptions and lag. Faced with today’s generations’ enthusiasm for live feeds, researchers are now working to adapt live streaming TV so it can be done on the go. The Goal: Lag-Free Live Streams Getting closer to what’s happening live is one of the main challenges in the field of live streaming. Yet, streaming over the Internet using Wi-Fi or 4G still results in a lag of 30, 40 or even 50 seconds on tablets or smartphones. This lag will particularly hit home for any soccer fans who have ever heard their neighbor watching TV and cheering for a goal they haven’t seen yet. It also affects participants in time-limited interactive TV game shows and televised broadcasts by figures of authority in relation to announcements, alerts or disasters, for example. Ensuring service continuity, particularly when faced with high demand, is another challenge of live streaming. At Orange Innovation, researchers are therefore thinking about how they can make improvements in the field of TV streaming on the go, using a combination of 5G, video streaming technologies (multicast, low latency), network bandwidth allocation (network slicing) and edge computing. Their work has primarily focused on mutualizing streams; a key way of saving bandwidth. Dominique Thômé, Product Manager Innovation Data TV, explains that “Unlike unicast technology, which broadcasts streams as many times as there are simultaneous connections, multicast should allow a single stream to be broadcast to thousands of people connected to a large 5G zone. This mutualization prevents bandwidth loss and, consequently, service interruptions from network congestion. Another advantage, which is of great importance to Orange, is that it consumes less energy and therefore contributes to the transition to a low-carbon economy.” Recognizing the Know-How of Carriers Experiments carried out in the Orange laboratory have yielded interesting results. A real-time readjustment of video quality to prevent network saturation resulted in each customer being able to watch TV with only five seconds of lag, confirming the feasibility of 5G live streaming on the go. In fact, faced with ever-increasing volumes, some broadcasters are beginning to turn to carriers to broadcast their TV streams. They need players that are able to transmit this huge amount of data while ensuring optimal quality, in order to avoid any latency problems. Thibaut Mathieu, Director of Innovation for Interactive & Multiscreen Services at Orange says that “Our pioneering approach toward 5G live streaming highlights the valuable role that network carriers play, right at the heart of the system, compared to OTT players (“over the top,” such as the Tech Giants), both in terms of technology and business. We will be able to get involved in data transmission, with optimal mutualization technology that will save money and energy.” These technologies are consistent with Orange’s CSR commitment, both in terms of carbon footprint (lower energy consumption) and inclusion (broadcasting the right information at the right time). More than Just Entertainment The challenge goes far beyond the traditional TV broadcasting market itself. In the context of the health crisis, brands have been quick to understand the value of live streams to generate sales and are starting to venture into “Live Shopping.” Originating from China, this large-scale approach to teleshopping consists of an online event where presenters, influencers or personalities showcase products live to a digital audience who are able to order products or ask questions. Live Shopping is attracting more and more brands around the world. “With hundreds of thousands of people connected at the same time, its large scale will certainly create capacity issues” says Thômé. “This is another case where mutualization will ensure quality of service.”

How 5G Is Revolutionizing Live Streaming

Discover