Abstract
Due to the large number of users and the time-varying characteristics of wireless channels, it is very tough to inform the transmitter of full channel information in real multi-user MIMO broadcast systems. On the other hand, the capacity of multi-user systems greatly depends on the knowledge of the channel at the transmitter while this is not always the case in single-user MIMO systems. In this paper, we investigate combined user selection and zero-forcing precoding schemes that use partial channel information, i.e., very low amount of channel information at the base station. We show that while greatly reducing the complexity and channel knowledge feedback load, the proposed schemes preserve the optimality of zero-forcing scheme in term of achievable ergodic sum capacity in limit of large number of active users.
Highlights
Linear precoding is an effective tool to achieve better performance and higher throughput in multiple-inputmultiple-output (MIMO) communication systems
We investigated the design of a partial knowledge based precoding scheme for broadcast MIMO systems
We proposed various combined user selection and precoding schemes with no or small amount of channel feedback and low complexity, which can achieve the performance of full knowledge schemes in the limit of large number of users
Summary
Linear precoding is an effective tool to achieve better performance and higher throughput in multiple-inputmultiple-output (MIMO) communication systems. We investigate downlink precoding schemes that is capable of achieving the capacity of a MIMO broadcast channel in which a multiple-antenna transmitter communicates with a number of mobile units This approach is based on the assumption of partial channel side information available at the transmitter while each receiver has perfect channel knowledge. We propose zero-forcing transmission schemes that use only partial channel information with low feedback load and facilitate the algorithm of selecting the best users at the transmitter It reduces the feedback load and algorithm complexity, it can be shown that its performance can be comparable to that of the scheme proposed in [15] in term of achievable rate. This gives a degree of robustness to the system that can cope with channel impairments and changes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Communications, Network and System Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
