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Adv. Signal Process."],"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Two-stage precoding schemes have been developed to reduce the channel estimation overhead in FDD systems. By integrating user scheduling into these schemes, it becomes possible to meet the quality-of-service requirements of high-density wireless communication systems, despite the limitations on spatial resources and transmit power budget. In this paper, we propose a user scheduling and dynamic beam allocation method for neighbor-based joint spatial division multiplexing (N-JSDM) transmission. The user scheduling problem is formulated as a 0\u20131 quadratic programming problem to maximize effective spectral efficiency (ESE) using directional channel properties. To address the complexity issue, convex relaxation and linearization methods are employed to transform the problem into a 0\u20131 mixed integer linear programming, and a dimensionality reduction method is introduced. The proposed user scheduling-aided N-JSDM scheme reduces downlink training length and feedback of channel state information. Additionally, a dynamic configuration form is used for pre-beamforming matrix design based on user distribution, outperforming conventional approaches. Simulation results demonstrate higher ESE achieved by the proposed scheme compared to previous methods.<\/jats:p>","DOI":"10.1186\/s13634-023-01099-8","type":"journal-article","created":{"date-parts":[[2024,1,2]],"date-time":"2024-01-02T11:02:24Z","timestamp":1704193344000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Neighbor-based joint spatial division and multiplexing in massive MIMO: user scheduling and dynamic beam allocation"],"prefix":"10.1186","volume":"2024","author":[{"given":"Huibin","family":"Liang","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9532-7721","authenticated-orcid":false,"given":"Chen","family":"Liu","sequence":"additional","affiliation":[]},{"given":"Yunchao","family":"Song","sequence":"additional","affiliation":[]},{"given":"Tianbao","family":"Gao","sequence":"additional","affiliation":[]},{"given":"Yulong","family":"Zou","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2024,1,2]]},"reference":[{"key":"1099_CR1","doi-asserted-by":"publisher","unstructured":"I.F. 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