Implementation and Analysis of 3D Channel Emulation Method in Multi-Probe Anechoic Chamber Setups

Weimin Wang,Yongle Wu,Ruru Wang,Huaqiang Gao

doi:10.1109/access.2019.2933494

Abstract

The multi-probe anechoic chamber (MPAC) based method is a candidate to assess the performance of multiple input multiple output (MIMO) devices over the air. This paper investigates the core problem, channel emulation method (CEM), in MPAC setups. The CEM is utilized to map the desired channel onto the limited number of probes to synthesize the target channel environment within a certain test area. In addition, the channel in realistic propagation environment is a three-dimensional (3D) channel, which can achieve higher data transmission rate by containing both azimuth and elevation dimension. Hence, it is urgent to investigate the CEM for 3D channels in MPAC setups. In this paper, the implementation of a novel CEM for 3D channels is presented, which allocates the subpaths in a simple way and complements the drawbacks of prefaded synthesis method and spatial fading emulator. Furthermore, the impact of the target channel and probe configuration on the emulation accuracy in terms of temporal correlation function (TCF) and spatial correlation function (SCF) is discussed. Simulation results demonstrate that the emulation accuracy of TCF depends more on the motion direction of MIMO devices while that of SCF depends more on the probes distribution. Moreover, probes number decides the emulation accuracy first. If the same number of probes are applied, the coincidence of the probe configuration and the target channel determines the emulation accuracy.

Highlights

In order to meet the need of increasing data transmission rate, multiple input multiple output (MIMO) technique, which exploits the characteristic of the multipath channel without additional bandwidth or transmitting power [1], [2], is widely utilized in the radio communication system
In this paper, we propose the implementation of the reference method to emulate 3D channels
We investigate the impact of the target channel and probe configuration on the emulation accuracy in terms of temporal correlation function (TCF) and spatial correlation function (SCF) under different conditions

Summary

INTRODUCTION

In order to meet the need of increasing data transmission rate, multiple input multiple output (MIMO) technique, which exploits the characteristic of the multipath channel without additional bandwidth or transmitting power [1], [2], is widely utilized in the radio communication system. W. Wang et al.: Implementation and Analysis of 3D Channel Emulation Method in MPAC Setups a cluster which has a specific shaped power angular spectrum according to different propagation environments. The emulation accuracy for 3D channels is investigated in terms of TCF and SCF under different conditions, such as target channel model, and probe configuration. Compared with PFS and SFE to synthesize channels from the perspective of clusters, each probe transmits several subpaths according to channel models and angular locations of probes in the reference method. For the uniform angular sampling method and uniform power sampling method, the initial number of subpaths on each probe rings is twice the number of probes on the same elevation angles. Because PDP and XPR can be reconstructed accurately by setting appropriate power and polarization for each cluster and polarization dimension, they are omitted in this paper

TEMPORAL CORRELATION FUNCTION

SIMULATION ANALYSIS

IMPACT OF TARGET CHANNEL ON EMULATION ACCURACY

CONCLUSION