Modulation-mode and power-assignment for SVD-and GMD-assisted downlink MIMO systems

Multiuser multiple-input multiple-output (MIMO) downlink (DL) transmission schemes experience both multiuser interference (MUI) as well as inter-antenna interference. However, instead of treating all the users jointly as in zero-forcing (ZF) multiuser transmission techniques, the investigated singular value decomposition (SVD) and geometric mean decomposition (GMD) assisted DL multiuser MIMO systems take the individual user's channel characteristics into account. The performed joint optimization of the number of activated MIMO layers and the number of bits per symbol along with the appropriate allocation of the transmit power shows that not necessarily all user-specific MIMO layers have to be activated in order to minimize the overall BER under the constraint of a fixed data throughpu

Performance Analysis of SVD-assisted Downlink Multiuser MIMO Systems

Multiuser multiple-input multiple-output (MIMO) downlink (DL) transmission schemes experience both multiuser interference as well as inter-antenna interference. Instead of treating all the users jointly as in zero-forcing (ZF) multiuser transmission techniques, the investigated singular value decomposition (SVD) assisted DL multiuser MIMO system takes the individual user’s channel characteristics into account. This translates to a choice of modulation constellation and transmitter power and, in our proposed system, to a choice of number of activated user-specific MIMO layers. The performed joint optimization of the number of activated MIMO layers and the number of bits per symbol along with the appropriate allocation of the transmit power shows that not necessarily all user-specific MIMO layers has to be activated in both frequency-selective and non-frequency selective MIMO channels in order to minimize the overall BER under the constraint of a given fixed data throughput

Modulation-mode assignment for SVD-assisted and iteratively detected downlink multiuser MIMO transmission schemes

In this contribution we jointly optimize the number of multiple-input multiple-output (MIMO) layers and the number of bits per symbol within an iteratively-detected multiuser MIMO downlink (DL) transmission scheme under the constraint of a given fixed data throughput and integrity. Instead of treating all the users jointly as in zero-forcing (ZF) multiuser transmission techniques, the investigated singular value decomposition (SVD) assisted DL multiuser MIMO system takes the individual user's channel characteristics into account. In analogy to bit-interleaved coded irregular modulation, we introduce a MIMO-BICM scheme, where different user-specific signal constellations and mapping arrangement were used within a single codeword. Extrinsic information transfer (EXIT) charts are used for analyzing and optimizing the convergence behaviour of the iterative demapping and decoding. Our results show that in order to achieve the best bit-error rate, not necessarily all user-specific MIMO layers have to be activate

Modulation-mode and power-assignment for SVD-assisted downlink multiuser MIMO systems

Multiuser multiple-input multiple-output (MIMO) downlink (DL) transmission schemes experience both multiuser interference as well as inter-antenna interference. However, instead of treating all the users jointly as in zero-forcing (ZF) multiuser transmission techniques, the investigated singular value decomposition (SVD) assisted DL multiuser MIMO system takes the individual user's channel characteristics into account. The performed joint optimization of the number of activated MIMO layers and the number of bits per symbol along with the appropriate allocation of the transmit power shows that not necessarily all user-specific MIMO layers has to be activated in order to minimize the overall BER under the constraint of a given fixed data throughput

SVD Aided Joint Transmitter and Receiver Design for the Uplink of Multiuser Detection Assisted MIMO Systems,

A novel singular value decomposition (SVD) aided uplink (UL) multiuser MIMO system is proposed. In contrast to the traditional minimum mean square error (MMSE) or zeroforcing (ZF) multiuser detection (MUD) technique, the proposed method exploits the specific characteristics of the individual users’ channel matrix, instead of treating all the users’ channels jointly. Furthermore, two different power allocation schemes are investigated in the context of the proposed structure. One of them was designed for achieving the maximum information rate, while the other for maintaining the maximum signal-to-noise ratio (SNR). We demonstrate that the capacity of the proposed scheme using the maximum information rate based power allocation policy is higher than that of the classic ZF receiver for the UL