Spectral Efficiency of the Multiway Massive System over Rician Fading Channels

Junyi He,Junnan Zhang,Mengxiang Wu,Cheng Song,Khaled Maaiuf Rabie

doi:10.1155/2021/6618363

Junyi He, Junnan Zhang + Show 3 more

Open Access

https://doi.org/10.1155/2021/6618363

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Abstract

In this study, we consider a multiway massive multi-input multi-output (MIMO) relay network over Rician fading channels, where all users intend to share their information with the other users via amplify-and-forward (AF) relays equipped with a great number of antennas. More practical, the imperfect channel state information (CSI) is taken into account. To evaluate the performance of the considered networks, we derived an analytical approximation expression for the spectral efficiency with zero-forcing (ZF) receivers in a closed form. To obtain more insights, the asymptotic analysis as the number of relay antenna approaching infinity is carried out. Finally, the power scaling law is analyzed for two scenarios. The results reveal that (1) massive MIMO is capable of compensating the loss caused by Rician fading, (2) the sum spectral efficiency increases with the increase of the Rician factor, and (3) deploying large-scale antenna is effective to save cost and keep performance.

Highlights

Massive multiple-input multiple-output in mobile communication technology networks has greatly improved the fluency and stability of communication and provides users with a better experience, which has been defined as a core technology of the fifth generation mobile [1, 2]
Multiway relay networks have a significant role on practical application scenarios, e.g., data transmission in multimedia conference call and exchanging information occurring in sensor nodes and data centres in wireless communication [7, 8]. anks to the multiplexing gain, multiway relay networks have become an upgrading technology to further push the performance of spectral efficiency of relay networks [9, 10]
E main contributions of the study are shown as follows: (1) With fixing the value of the Rician factor and comparing the trend of the sum spectral efficiency, we find out that massive multi-input multi-output (MIMO) can compensate the loss caused by Rician fading; (2) e sum spectral efficiency grows logarithmic when the Rician fading factor K grows, and the spectral efficiency presents highlight when K 0; (3) Using the estimated amount obtained, the closed form for the spectral efficiency with ZF processing is obtained

Summary

Introduction

Massive multiple-input multiple-output in mobile communication technology networks has greatly improved the fluency and stability of communication and provides users with a better experience, which has been defined as a core technology of the fifth generation mobile [1, 2]. Authors in [12] derive multiway massive MIMO relay networks in wireless communication and the technology of power transfer at the same time. It is shown in [13] that the transmit powers at user and relay nodes can be reduced with large antenna array and keep a fixed quality of service in the multiway massive MIMO networks. Motivated by the above discussion, we consider a multiway massive MIMO relay network over Rician fading channels with ZF processing in this study. By utilizing the ZFR/ZFT algorithm, we obtain an approximate analytical evaluation for the spectral efficiency of considered multiway massive MIMO relay networks in close. When using TDD operation, there are three parts in each coherence interval: channel estimation, multiple access phase, and broadcasting phase

Network Model

Information Transmission

Spectral Efficiency Analysis

Power Scaling Laws

Conclusions