讲座题目：Omnidirectional Precoding for Massive MIMO with Uniform Rectangular Array
主讲人：王昕教授、复旦大学
开始时间：2019-11-22(周五) 上午10点
讲座地点：闵行校区信息楼240报告厅
主讲人简介：
王昕，1997年、2000年获复旦大学电子工程系学士、硕士学位，2004年获美国奥本大学电子和计算机工程博士学位。2004－2006年在美国明尼苏达大学从事博士后研究，2006－2012年在美国佛罗里达大西洋大学（FAU）任教，于2010年提前两年获得终生教职并晋升为副教授。现为复旦大学特聘教授、通信科学与工程系主任。主要从事宽带无线网络、通信信号处理、跨层网络设计、高能效绿色通信等领域的研究。在IEEE国际期刊发表SCI收录论文65篇，包括发表在无线通信领域最重要的IEEE期刊上共63篇。获国家青年特聘专家、上海市特聘专家称号；担任IEEE杰出讲师（Distinguished Lecturer）、IEEE信号处理旗舰期刊TSP的高级领域编辑（Senior Area Editor）及IEEE无线通信旗舰期刊TWC的编辑（Editor）。
讲座摘要：
In the public channels, it is desirable to transmit the common signals omnidirectionally to ensure cell-wide coverage. In this talk, we first develop low-cost closed-form omnidirectional precoding designs for a massive multiple-input multiple-output (MIMO) system equipped with a uniform rectangular array (URA). In particular, we derive an optimal solution based on the complementary set (CS) or the complete complementary codes (CCC). We prove that the precoding vectors based on the CS or CCC sequences can generate a perfectly flat radiation-power pattern. Since both CS and CCC sequences are binary and constant-modulus, the proposed schemes are well suited to be implemented in the radio frequency (RF) analog domain with low hardware cost and suppressed peak-to-average power ratio (PAPR). The design of the proposed closed-form schemes relies on the existence of the corresponding CS or CCC for a given URA configuration. To overcome the limitations, we further develop an iterative rank-reduction algorithm. It is shown that the proposed algorithm can always obtain three precoding vectors to generate a perfectly flat radiation-power pattern for any URA configuration. By further imposing the constant-modulus constraints for every entries of the precoding matrix, we propose a Newton’s method, which can always obtain a rank-4 omnidirectional precoding matrix for a general URA. The proposed numerical optimzation based schemes complement well the CS- and CCC-based schemes. Overall, this work provides a unified approach to omnidirectional precoding for massive MIMO equipped with URA.
