Non-uniform activation boosts distributed MIMO wireless efficiency
Non-Uniform Activation Aided Distributed Generalized Spatial Modulation for DMIMO Systems
Information Theory
Summary
Wireless communication systems with multiple antennas work better when the signals from multiple transmission points are carefully coordinated. This paper looks at a new way to improve this by activating different groups of transmission points at different chances, instead of all the same. The authors designed a method to decide how likely each group should be active and how much power to use, maximizing data transmission. Their approach showed better use of wireless capacity compared to earlier methods that used uniform activation.
What this means in practice
- •For wireless network engineers: Increase data rates in multi-transmitter cell networks by optimizing which transmission points are activated and how much power they use together.
- •For cellular infrastructure designers: Design distributed antenna layouts that improve spectral efficiency by adapting activation probabilities to different antenna subsets for downlink communication.
Authors
Haojin Li, Chen Sun, Rang Su, Zhaojian Liu, Wenqi Zhang, Haijun Zhang
Abstract
This letter investigates a non-uniform activation aided distributed generalized spatial modulation (DGSM) scheme in a downlink distributed multiple-input multiple-output (DMIMO) system formed by geographically separated transmission reception points (TRPs). Unlike conventional uniform-activation DGSM, the proposed scheme assigns adaptive activation probabilities to different TRP subsets, thereby jointly exploiting the data-domain transmission capability and the index-domain information carried by cooperative subset selection. We derive a mutual-information upper bound under non-uniform activation and formulate a joint activation-probability and power allocation problem subject to a long-term average power constraint. To solve this problem, we develop a semi-closed-form joint probability and power optimization (SC-JPPO) algorithm, where the optimal activation probabilities are shown to follow a Softmax function of the effective utilities. Simulation results demonstrate that the proposed scheme improves spectral efficiency under the same activation scale and power budget compared with existing benchmarks.