Abstract

G communication is likely to be deployed in high frequency band (e.g., 28 GHz). An accurate channel model is necessary to evaluate system performance at initial design phase. However, the valid frequency of 3D SCM channel models developed in 2014 is 2 – 6 GHz. It is not suitable for millimeter band. In order to solve this problem, a new study item on NR channel model was initiated by 3GPP in 2016. The NR channel model consists of common components and extended components. The common components specify the mathematical model and the algorithms used for channel coefficient generation. The extended components are used to model the physical phenomenon of millimeter frequency band. In this paper, we will introduce the NR channel model. Besides, the channel calibration process will also be described.

Index Terms—5G, Channel model, SCM, Pathloss, Penetration loss, Calibration

I. INTRODUCTION

I. INTRODUCTION
I
N order to fulfil the 5G requirements on IMT-2020, the 3rd generation parternership project (3GPP) approved a new study item (SI) on New Radio Access Technology (NR) in March 2016. The NR system focuses on three usage scenarios: enhanced Mobile Broadband (eMBB), massive Machine Type Communications (mMTC) and Ultra-Reliable and Low Latency Communications (URLLC). Although 3GPP had completed a study on 3D SCM channel models in 2014 [2], its applied frequency range is 2 – 6 GHz. A new channel model is necessary for the performance evaluation of higher frequency bands (above 6 GHz). Thus a new study item on NR channel model [3] was initiated by 3GPP in 2016 and a lot of channel measurement results are contributed by industry and academic members.
The design objectives and requirements of NR channel model are as follows:
• Channel model SI should take into account the outcome of RAN-level discussion in the 5G requirement study item.
• Complexity in terms of generating channel coefficients, development complexity and simulation time should be considered.
• Support frequency range up to 6 – 100 GHz.
• Take care of mmW propagation aspects such as blocking and atmosphere attenuation.
• The model should be consistent in space, time and frequency.