{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:15:43Z","timestamp":1760242543973,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,10,25]],"date-time":"2017-10-25T00:00:00Z","timestamp":1508889600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61561032","61703197","61461029"],"award-info":[{"award-number":["61561032","61703197","61461029"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"China the Jiangxi Postdoctoral Science Foundation Funded Project","award":["2014MT561879","2014KY046"],"award-info":[{"award-number":["2014MT561879","2014KY046"]}]},{"name":"Young Scientists Project Funding of Jiangxi Province","award":["20153BCB23020","20162BCB23010"],"award-info":[{"award-number":["20153BCB23020","20162BCB23010"]}]},{"DOI":"10.13039\/501100004479","name":"Natural Science Foundation of Jiangxi Province","doi-asserted-by":"publisher","award":["20114ACE00200"],"award-info":[{"award-number":["20114ACE00200"]}],"id":[{"id":"10.13039\/501100004479","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Graduate Student Innovation Special Funds","award":["cx2016263"],"award-info":[{"award-number":["cx2016263"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this paper, we consider the precoding design and power allocation problem for multi-user multiple-input multiple-output (MU-MIMO) wireless ad hoc networks. In the first timeslot, the source node (SN) transmits energy and information to a relay node (RN) simultaneously within the simultaneous wireless information and power transfer (SWIPT) framework. Then, in the second timeslot, based on the decoder and the forwarding (DF) protocol, after reassembling the received signal and its own signal, the RN forwards the information to the main user (U1) and simultaneously sends its own information to the secondary user (U2). In this paper, when the transmission rate of the U1 is restricted, the precoding, beamforming, and power splitting (PS) transmission ratio are jointly considered to maximize the transmission rate of U2. To maximize the system rate, we design an optimal beamforming matrix and solve the optimization problem by semi-definite relaxation (SDR), considering the high complexity of implementing the optimal solution. Two sub-optimal precoding programs are also discussed: singular value decomposition and block diagonalization. Finally, the performance of the optimization and sub-optimization schemes are compared using a simulation.<\/jats:p>","DOI":"10.3390\/sym9110247","type":"journal-article","created":{"date-parts":[[2017,10,25]],"date-time":"2017-10-25T11:13:27Z","timestamp":1508930007000},"page":"247","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Precoding Design and Power Allocation in Two-User MU-MIMO Wireless Ad Hoc Networks"],"prefix":"10.3390","volume":"9","author":[{"given":"Haole","family":"Chen","sequence":"first","affiliation":[{"name":"Information Engineering School, Nanchang University, Nanchang 330031, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lin","family":"Xiao","sequence":"additional","affiliation":[{"name":"Information Engineering School, Nanchang University, Nanchang 330031, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yinfeng","family":"Li","sequence":"additional","affiliation":[{"name":"Information Engineering School, Nanchang University, Nanchang 330031, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dingcheng","family":"Yang","sequence":"additional","affiliation":[{"name":"Information Engineering School, Nanchang University, Nanchang 330031, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoxiao","family":"Zhou","sequence":"additional","affiliation":[{"name":"Information Engineering School, Nanchang University, Nanchang 330031, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1109\/SURV.2011.060710.00094","article-title":"Energy Harvesting Sensor Nodes: Survey and Implications","volume":"13","author":"Sudevalayam","year":"2011","journal-title":"IEEE Commun. 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