The Study Of Polarized Multiple Antennas In TD-HSPA+ System

With the rapid development of wireless communication technology, the requirements for high-speed and high-quality data services are increasing. To meet this challenge and smoothly evolve to the time division duplex long term evolution (TDD-LTE) system,3GPP has introduced the concept of time division high speed package access plus (TD-HSPA+), which is the advanced version of the time division high speed packet access (TD-HSPA) in Release 7. As a key technology of TD-HSPA+, the multi-antenna technique can dramatically improve the spectral efficiency and the robustness of the system with limited resources, and it has been a research hotspot for the last years. In this paper, both the downlink multi-user multiple-input multiple-output (MU-MIMO) and uplink single-user MIMO (SU-MIMO) with polarized antenna configurations are investigated and compared, and then the performances are further evaluated in the TD-HSPA+ system-level simulation platform to identify the gains. And what's more, the performance of the downlink MU-MIMO in the TD-HSPA+ link-level simulation platform is also evaluated.Firstly, in order to reduce the size of the Base Station (BS), the 8 polarized transmitting antennas configuration is introduced into the TD-HSPA+ system as a SU-MIMO transmission scheme in the uplink. The basic principles and structure for polarized antenna in the TD-HSPA+ system are also introduced. Polarized antenna channel model is derived, and the performance difference between polarized antenna configuration and traditional linear array antennas is evaluated in the TD-HSPA+ system-level simulation platform in urban and suburban scenarios. Secondly, the polarized antenna channel model is analysed and evaluated for multi-user deployment in TD-HSPA+ link-level simulation. The analysis of performance is given and well discussed for the 8X2 MU-MIMO polarized antenna configuration.Finally, a MAX C/I based scheduling algorithm combined with a SVD based precoding scheme is proposed for TD-HSPA+ MU-MIMO polarized antenna downlink system. And it is also introduced into the TD-HSPA+ MU-MIMO simulation platform to evaluate the performance of cross polarization in the system. The grouped beamforming and joint beamforming schemes for 8X2 MU-MIMO polarized antenna configuration are designed and compared. Furthermore, the performance difference between polarized antenna configuration and traditional linear array antenna configuration are also evaluated in urban macro and urban micro scenarios.