Downlink Precoding for Cell-free FBMC/OQAM Systems With Asynchronous Reception

Antenna Selection SFN Precoding Scheme for Downlink Cooperative MIMO Systems

Recently, there has been considerable interest in cooperative multiple-input multiple-output (MIMO) systems, where the data intended for a user equipment (UE) is simultaneously transmitted from multiple base stations (BSs). In [1], the authors investigated cooperative MIMO as a means to mitigate co-channel interference and to exploit macro-diversity for the Wyner’s model and its variants. Moreo...

Precoding Schemes for MIMO Downlink Transmission

Multi – User Downlink Precoding in Fdd Systems without Channel Feedback

In this contribution we present a new method for multi – user MIMO downlink precoding in Frequency Division Duplex (FDD) systems. In order to avoid channel feedback, we estimate the long term channel statistics (spatial covariance matrix) based on the received uplink data. Afterwards we transform the receive spatial covariance matrix to the downlink frequency and use this data to calculate an e...

Hierarchical Precoding for the Network MIMO Downlink

Over the last few years, network MIMO or distributed MIMO has gained enormous interest in research and meanwhile is a candidate for future communication systems. However, existing techniques handling the multi-user interference, e.g., linear preequalization (LPE) or TomlinsonHarashima precoding (THP), assume full cooperation between the base stations. This might cause significant signaling over...

Joint signal precoding in the downlink of spread-spectrum systems

The downlink capacity tends to be the limiting factor in future communications systems. In this paper, we propose two schemes for the downlink of code-division multiple-access systems that help reduce the multiuser interference by jointly precoding the transmitted signal based on knowledge of the downlink channel. Methods that operate on blocks of bits will be first developed and a bitwise simp...