针对非同构分布式阵列无法使用旋转不变子空间算法(estimation of signal parameters via rotation invariant technique algorithm,ESPRIT),同时为了提高非同构分布式阵列的角度估计精度,提出基于求根降秩算法(root rank reduction est...针对非同构分布式阵列无法使用旋转不变子空间算法(estimation of signal parameters via rotation invariant technique algorithm,ESPRIT),同时为了提高非同构分布式阵列的角度估计精度,提出基于求根降秩算法(root rank reduction estimator,root-RARE)的目标波达方向估计方法。由于分布式阵列的基线长度远大于半波长,合成方向图出现栅瓣,导致测角模糊。算法以root-RARE与多重信号分类算法(multiple signal classification,MUSIC)联合解模糊,以root-RARE得到的粗估计为参考,解整个非同构分布式阵列MUSIC谱估计的模糊,从而得到高精度无模糊的估计。推导非同构分布式阵列方向估计的克拉美罗界,分析算法的波达方向估计性能,同时分析分布式阵列方向估计时的基线模糊门限与信噪比门限之间的关系。仿真结果验证所提算法方向估计的正确性及有效性。展开更多
This work focuses on the multicell multi-user distributed massive MIMO(DM-MIMO)systems,of which each user is equipped with single antenna and the base stations(BSs)consists of distributed antenna units. We first inves...This work focuses on the multicell multi-user distributed massive MIMO(DM-MIMO)systems,of which each user is equipped with single antenna and the base stations(BSs)consists of distributed antenna units. We first investigate the arbitrary BS antenna topology scenario. The derivation indicates that in this case the achievable uplink rate of an arbitrary user in central cell depends on both the number of BS's antennas and the users' access distance to each distributed antenna unit(DAU). As a result,the performance analysis based on the derivations is difficult. To overcome this issue and achieve clearer insight,we then consider a circularly distributed BS antenna array and obtain the asymptotic uplink rate of an arbitrary user by considering the asymptotic case where the number of antennas of BSs tends to infinity. It is achieved that the asymptotic uplink rate only depends on the distance from users' position to the center of reference cell. The presented numerical results show clearly that the distributed massive MIMO systems outperform the centralized ones. Moreover,it is also achieved that the interference from the adjacent cells imposes great impact on system performance. Besides this,in numerical analysis the averageasymptotic uplink rate of a user is presented,which is free of the users' position and only depends on the radius of circular antenna arrays. It is achieved the maximum average uplink rate would be achieved when the radius of circularly distributed antenna array goes to its optimization location.展开更多
文摘针对非同构分布式阵列无法使用旋转不变子空间算法(estimation of signal parameters via rotation invariant technique algorithm,ESPRIT),同时为了提高非同构分布式阵列的角度估计精度,提出基于求根降秩算法(root rank reduction estimator,root-RARE)的目标波达方向估计方法。由于分布式阵列的基线长度远大于半波长,合成方向图出现栅瓣,导致测角模糊。算法以root-RARE与多重信号分类算法(multiple signal classification,MUSIC)联合解模糊,以root-RARE得到的粗估计为参考,解整个非同构分布式阵列MUSIC谱估计的模糊,从而得到高精度无模糊的估计。推导非同构分布式阵列方向估计的克拉美罗界,分析算法的波达方向估计性能,同时分析分布式阵列方向估计时的基线模糊门限与信噪比门限之间的关系。仿真结果验证所提算法方向估计的正确性及有效性。
基金supported by the Natural Science Foundation of China under Grant 61261015 and 61561043the 973 project 2013CB329104,the Natural Science Foundation of China under Grant 61372124,61363059,and 61302100+1 种基金the projects BK2011027,the Natural Science Foundation of Gansu Province for Distinguished Young Scholars(1308RJDA007)by the Foundation Research Funds for the University of Gansu Province:‘Massive MIMO channels modeling and estimation over millimeter wave band for 5G’
文摘This work focuses on the multicell multi-user distributed massive MIMO(DM-MIMO)systems,of which each user is equipped with single antenna and the base stations(BSs)consists of distributed antenna units. We first investigate the arbitrary BS antenna topology scenario. The derivation indicates that in this case the achievable uplink rate of an arbitrary user in central cell depends on both the number of BS's antennas and the users' access distance to each distributed antenna unit(DAU). As a result,the performance analysis based on the derivations is difficult. To overcome this issue and achieve clearer insight,we then consider a circularly distributed BS antenna array and obtain the asymptotic uplink rate of an arbitrary user by considering the asymptotic case where the number of antennas of BSs tends to infinity. It is achieved that the asymptotic uplink rate only depends on the distance from users' position to the center of reference cell. The presented numerical results show clearly that the distributed massive MIMO systems outperform the centralized ones. Moreover,it is also achieved that the interference from the adjacent cells imposes great impact on system performance. Besides this,in numerical analysis the averageasymptotic uplink rate of a user is presented,which is free of the users' position and only depends on the radius of circular antenna arrays. It is achieved the maximum average uplink rate would be achieved when the radius of circularly distributed antenna array goes to its optimization location.
