Article Sidebar
Published:
Jun 22, 2026Keywords:
Article Details
In accordance with the Copyright Act of 1976, which became effective January 1, 1978, the following statement signed by each author must accompany the manuscript submitted: "I, the undersigned author, transfer all copyright ownership of the manuscript referenced above to the Nigerian Journal of Technological Development, in the event the work is published. I warrant that the article is original, does not infringe upon any copyright or other proprietary right of any third party, is not under consideration by another journal, and has not been published previously. I have reviewed and approve the submitted version of the manuscript and agree to its publication in the Nigerian Journal of Technological Development." A copyright transfer form may be downloaded from the NJTD Website (http://njtd.com.ng/index.php/njtd). Author(s) will be consulted, whenever possible, regarding republication of material. All authors must have access to the data presented and the authors and sponsor (if applicable) must agree to share original data with the editor if requested.
Main Article Content
User correlation using rotating planar antenna arrays for line-of-sight massive multiple input multiple output
Abstract
This work investigates an array antenna rotation (AAR) technique in order to minimize inter-user correlation for massive multiple-input-multiple-output (MIMO) in pure line-of-sight (LoS) environment. Traditional planar arrays have better signal separation performance than linear arrays and can create three dimensional beams. However, when the angular separation of some signals between the users from/to the base station (BS) are small, the interference suppression (i.e., signal separation) performance degenerates since the projection points onto horizontal and vertical axes of several antenna elements overlap and spatial resolution along each axis is degraded. The aim is to improve inter-user correlation performance via mechanical rotation angle optimization. We propose a recursive bisection algorithm for rotation angle optimization by finding the optimal antenna rotation angle. Simulation results show in particular that the rotation of antenna body at the BS has inter-user correlation impact on large number of antennas in both horizontal and vertical resolutions. The 5th percentile inter-user correlation values of 8 × 16, 16 × 32, 32 × 64, 64 × 128 and 128 × 136 AAR configurations are 0.96, 0.86, 0.53, 0.03, and 0.00, respectively. This means that inter-user correlation increases with decrease in number of antennas and can be achieved in practice. Finally, the spatial decorrelation of AAR is superior compared to parallelogram planar array (PPA) and uniform planar array (UPA) because of mechanical rotation of antenna body.
