Major breakthrough on mmWave propagation and channel modeling

Understanding radio propagation in the mmWave frequency range is vital for the development of 5G. Ericsson Research experts, in partnership with European researchers in the mmMAGIC project, have performed extensive mmWave channel measurements and modeling for a multitude of scenarios. Let’s look at our key achievements.

Present cellular communications systems utilize frequencies below 6 GHz. The frequency range 24-86 GHz – which is subject for allocation within International Mobile Telecommunication 2020 (IMT-2020) spectrum at the World Radiocommunication Conference 2019 – is however mainly in the mmWave range. Compared with below 6 GHz, loss in radio signal due to absorption in materials or blockage by buildings, vegetation, vehicles, and humans is expected to be substantially different in the mmWave range. Moreover, important radio channel characteristics such as multi-path delay spread and directional spread have previously been poorly understood in the mmWave range.

To overcome this knowledge gap, the mmMAGIC project (co-funded by the European Commission’s H2020 program) has undertaken a major effort in the area of propagation research with extensive measurement campaigns performed over 2-80 GHz for a multitude of different indoor and outdoor scenarios. In addition, researchers have performed simulation campaigns in selected popular environments and frequencies to provide a large data set of propagation channels for the purpose of channel modelling. Overall, 54 single-frequency equivalent campaigns have been conducted. An overview of these measurements and simulations is depicted in figure below.

Requirements for channel measurements

The assessment of any frequency dependency over the measured range is key in the development of 5G mobile communications and spectrum allocation. To ensure comparability between channel measurements at different frequencies, a set of important requirements have been established:

  • Equal measurement bandwidth
  • Equal antenna pattern, either physical or synthesized
  • Equal dynamic range for analysis both in delay and angle domains
  • Equal angle resolution (for example, array size equal in terms of number of lambda)
  • Same environment and same antenna locations

The measurement data in the mmMAGIC project has been thoroughly analyzed assuring that the above requirements were fulfilled.

Key results and contributions in channel modeling

Based on channel measurements and thorough analysis, the key characteristics of mmWave propagation can now be largely understood. All details are publicly available in the project’s final report Measurement Results and Final mmMAGIC Channel Models. The key results have, to a large extent, already been incorporated into propagation models in 3GPP and ITU-R, as listed below:

  1. Extensive high quality measurement data contributed to 3GPP 5G channel modeling.
  2. Measurements and modeling of building penetration loss used as substantial input to 3GPP and ITU-R models.
  3. A substantially improved blockage model adopted by ITU-R.
  4. Addition of ground reflection added to ITU-R IMT2020 channel model.

Thorough statistical analysis (determining confidence ranges shown in the figure) of frequency dependency of delay spread and angle spread, with no significant frequency dependency observed, in contrast to the less thorough result of the 3GPP modelling effort.

Indoor measurement of angle spread in line of sight (LOS) and non-line of sight (NLOS)
Indoor measurement of angle spread in line of sight (LOS) and non-line of sight (NLOS)
Frequency dependence of RMS delay spread of the 3GPP and mmMAGIC channel models. The confidence ranges of the mmMAGIC model are indicated with dashed lines.
Frequency dependence of RMS delay spread of the 3GPP and mmMAGIC channel models. The confidence ranges of the mmMAGIC model are indicated with dashed lines.

 

mmMAGIC project

The mmMAGIC consortium comprises of 18 organizations in Europe (Samsung, Ericsson, Huawei, Nokia, Alcatel-Lucent, Intel, Orange, Telefonica, Keysight Technologies, Rhode & Schwarz, HHI, CEA-Leti, Imdea Networks, Bristol University, Chalmers University, TU Dresden, Qamcom, Aatlo University). For details on the mmWave radio interface design, please visit the project webpage.

Author: Ali Zaidi

A Framework for Nokia AirScale Cloud RAN Technology

telxperts cellular data

With the introduction of state-of-the-art technologies, the mobile industry is going through a radical transformation. The network is expanding day by day as a result of smart cities, mobile living, the Internet of Things (IOT) with a large number of sensors, connected vehicles, e-health, and the list goes on. In order to meet the demands of the growing trend of Internet of Things (IoT) and increasingly high customer expectations, operators need to formulate a new approach towards building a network that will be able to deliver extreme low latency and massive broadband to meet widely diverse uses.

AirScale is a modernised and up-to-date technology which redefines the way radio networks are built. It is a complete package, which offers complete radio access generation running on traditional Distributed Radio Access Network (RAN) sites as well as centralised and Cloud RAN. AirScale technology is set to simultaneously run all radio technologies such as LTE-Advanced, LTE-Advanced Pro, TDD-LTE, FDD-LTE, 2G and 3G on a single base station as a Single RAN, thereby integrating carrier-grade Wi-Fi access, making itself 5G-ready and thus offering an unlimited capacity. Apart from this, it utilises 60 percent less energy compared to the Flex radio access platform, which is still widely used for energy efficiency purposes.

telxperts cellular data

Figure 1: An illustration of AirScale technology used in cellular network.

AirScale also provides a way to close the gap between the IT and Telco worlds. AirScale Cloud RAN is running on the same servers as Mobile Edge Computing (MEC). As a result, interfaces such as Application Programming are opened up to a number of new applications, services, and plug-ins integrated into the RAN. Rapid delivery of software is provided by Cloud RAN on an IT platform, bringing a new level of agility and performance to networks. The President of Mobile Networks of Nokia expressed his point of view regarding this technology as, “The world will witness immense changes over the next few years. Broadband traffic will continue to surge as people go beyond video and take advantage of augmented and virtual reality. The Internet of Things will see billions of devices connected, and 5G will enable new scenarios such as Industry 4.0, smart cities, e-health and mobile living. Nokia AirScale is designed from the ground up for this new era, while also introducing ground-breaking cloud-based capabilities.”

The capabilities of AirScale were demonstrated at Mobile World Conference (MWC) 2016, where operators were able to get their hands on the AirScale base stations and watch it run 5G with 5Gbps data rates and under 1ms latency. With its high performance and flexibility, AirScale will be able to support wide ranging applications such as ultra-reliable communications for autonomous vehicles, ultra-low latency connectivity for synchronising industrial robotics, new live broadcasting services at large events and much more.

To further know about LTE E-UTRAN Signaling and Air Interface, LTE-A Carrier Aggregation, Implementation, and Challenges you can join our 4G LTE E-UTRAN Architecture, Signaling and Air Interface and 4G LTE-A Certification Courses here.