Journal
IEEE SYSTEMS JOURNAL
Volume 15, Issue 2, Pages 2519-2530Publisher
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
DOI: 10.1109/JSYST.2020.2990709
Keywords
Additive quantization noise model (AQNM); cell-free massive multi-input multi-output (MIMO); Gaussian RF impairment model (GRFIM); low-resolution analog-to-digital converters (ADCs); RF impairments
Categories
Funding
- National Key Research and Development Program of China [2018YFC1314903]
- National Natural Science Foundation of China [61861039, 61372124, 61427801]
- Science and Technology Project Foundation of Gansu Province [18YF1GA060]
- Postgraduate Research and Practice Innovation Program of Jiangsu Province [SJKY19_0740]
Ask authors/readers for more resources
This article investigates a generalized uplink cell-free massive MIMO system with nonideal RF chains and low-resolution ADCs, finding that RF impairments and ADC imperfections affect channel estimation accuracy and received signal strength. The study shows that 5-bit ADCs can substitute infinite-bit ADCs with minimal performance degradation, and there is a compensation relationship between RF impairments and ADC imperfections.
In this article, a generalized uplink cell-free massive multi-input multi-output (MIMO) system with nonideal radio frequency (RF) chains and low-resolution analog-to-digital converters (ADCs) is investigated. Specifically, the RF impairments and ADC imperfections not only hinder the accuracy of channel estimation but also deteriorate the strength of received signal-to-interferenceplus-noise ratio. Achievable closed-form rate expressions are first derived by leveraging on the Gaussian RF impairment model and linear additive quantization noise model, after that, we explore the uplink achievable rate surrounding the key design parameters, i.e., the quality of RF chains, the precision of low-resolution ADCs, and the number of total antenna arrays. Considering channel estimation, we find employing poor RF chains and ADCs could fetch finite ceilings on estimation accuracy. Besides, the RF scaling law is also established, which suggests that the access points (APs) can tolerate lower receiver quality as the number of total antenna arrays increases, and the receiver quality can be cut down at most by 1/root MN, where M and N are the number of APs and the number of antennas of each AP, respectively. Moreover, we observe 5-bit ADCs are enough to substitute infinite-bit ADCs with scarce performance degradation. Finally, the compensation between RF impairments and ADC imperfections is presented. The resultant analysis provides insights for designing amore economical cell-free massive MIMO system while keeping the achievable rate at an acceptable level.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available