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Title: Uplink Energy Efficiency of Cell-Free Massive MIMO With Transmit Power Control in Measured Propagation Channels
Abstract—Cell-free massive MIMO (CF-mMIMO) is expected to provide reliable wireless services for a large number of user equipments (UEs) using access points (APs) distributed across a wide area. When the UEs are battery-powered, uplink energy efficiency (EE) becomes an important performance metric for CF-mMIMO systems. Therefore, if the “target” spectral efficiency (SE) is met, it is important to optimize the uplink EE when setting the transmit powers of the UEs. Also, such transmit power control (TPC) method must be tested on channel data from real-world measurements to prove its effectiveness. In this paper, we compare three different TPC algorithms using zero-forcing reception by applying them to 3.5 GHz channel measurement data featuring 30,000 possible AP locations and 8 UE locations in a 200m×200m area. We show that the max-min EE algorithm is highly effective in improving the uplink EE at a target SE, especially if the number of single-antenna APs is large, circuit power consumption is low, and the maximum allowed transmit power of the UEs is high.  more » « less
Award ID(s):
1923601 1731694
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
021 IEEE Workshop on Signal Processing Systems (SiPS)
Page Range / eLocation ID:
164 to 169
Medium: X
Sponsoring Org:
National Science Foundation
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