TY - JOUR
T1 - Spatiotemporal Modeling of Massive MIMO Systems with Mixed-Type IoT Devices
T2 - Scheduling Optimization with Delay Constraints
AU - Zhang, Qi
AU - Yang, Howard H.
AU - Quek, Tony Q.S.
AU - Jin, Shi
N1 - Publisher Copyright:
IEEE
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021
Y1 - 2021
N2 - In this paper, we develop a framework for the analysis of massive multiple-input multiple-output (MIMO) systems where multiple types of devices with different configurations and requirements co-exist, by taking into account the randomness of spatial locations and temporal traffic. A tight closed-form approximation of the spatial mean packet throughput which denotes the average number of packets that are successfully transmitted at any unit time slot and area is derived, by using tools from stochastic geometry and queuing theory, which captures all the key features of the devices in Internet of Things (IoT). Based on the analysis, we investigate the optimal scheduling number for each type of devices that maximizes the spatial mean packet throughput while meeting devices’ delay constraints. It is found that when the BS has excessive number of antennas (M), the BS should schedule all devices under its coverage, regardless of devices’ variances on spatiotemporal configurations and demands. However, when M is limited, the BS should have a bias on scheduling devices with heavier traffic, lower decoding threshold, or higher transmit power. On this basis, if the delay constraint of one device becomes stricter, it will be scheduled more often to access the radio channel, which acts more significantly when the ratio of M to the deployment density of devices gets smaller.
AB - In this paper, we develop a framework for the analysis of massive multiple-input multiple-output (MIMO) systems where multiple types of devices with different configurations and requirements co-exist, by taking into account the randomness of spatial locations and temporal traffic. A tight closed-form approximation of the spatial mean packet throughput which denotes the average number of packets that are successfully transmitted at any unit time slot and area is derived, by using tools from stochastic geometry and queuing theory, which captures all the key features of the devices in Internet of Things (IoT). Based on the analysis, we investigate the optimal scheduling number for each type of devices that maximizes the spatial mean packet throughput while meeting devices’ delay constraints. It is found that when the BS has excessive number of antennas (M), the BS should schedule all devices under its coverage, regardless of devices’ variances on spatiotemporal configurations and demands. However, when M is limited, the BS should have a bias on scheduling devices with heavier traffic, lower decoding threshold, or higher transmit power. On this basis, if the delay constraint of one device becomes stricter, it will be scheduled more often to access the radio channel, which acts more significantly when the ratio of M to the deployment density of devices gets smaller.
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U2 - 10.1109/JIOT.2021.3051055
DO - 10.1109/JIOT.2021.3051055
M3 - Article
AN - SCOPUS:85099539872
JO - IEEE Internet of Things Journal
JF - IEEE Internet of Things Journal
SN - 2327-4662
ER -