Linear precoding (beamforming) techniques that maximize the sum rate in the multi-antenna broadcast channel often suffer severe performance degradation when the channel state information at the transmitter is erroneous or outdated. This paper presents a linear precoding algorithm that uses the channel statistics rather than channel state to provide more stable performance in time-varying enviro...

A new system concept for high-rate digital transmission over twisted pair lines with precoding is presented. To avoid retransmission of channel data, lters at the transmitter side are xed and designed for a reference application. Intersymbol interference caused by mismatch of designed lters and actual situation, is cancelled by an adaptive FIR equalizer. Implementation is thereby simpli ed cons...

This paper addresses the problem of cooperation in a multicell environment where base stations wish to jointly serve multiple users, under a constrained-capacity backhaul. Such a constraint limits, among other things, data sharing and network MIMO concepts need to be revised accordingly. More precisely, we focus on the downlink, and propose to use the backhaul to transmit several messages to ea...

This report considers the effect of spatial correlation between transmit antennas on the sum-rate capacity of the MIMO Gaussian broadcast channel (i.e., downlink of a cellular system). Specifically, for a system with a large number of users n, we analyze the scaling laws of the sum-rate for the dirty paper coding and for different types of beamforming transmission schemes. When the channel is i...

In this letter, we propose a blind multiuser detector based on a new data precoding technique for direct-sequence codedivision multiple-access signals. In this technique, the modulus of all users' data is block encoded, using a sequence that is unique for each user. This precoding method, together with the analytical constant modulus algorithm for detection, enables a closedform, one-shot detec...

The downlink of a multiple-input multiple output (MIMO) broadcast channel (BC) is considered, where each receiver is equipped with a single antenna and the transmitter performs nonlinear Dirty-Paper Coding (DPC). We present an efficient algorithm that finds the optimum transmit filters and power allocation as well as the optimum precoding order(s) possibly affording time-sharing between individ...

This paper combines spatial Tomlinson-Harashima (TH) precoding with packet scheduling at the transmitter to improve the system-level performance of packet data systems. Under the assumptions of instantaneous and perfect channel state information (CSI) at the transmitter and independent and identically distributed (i.i.d.) user channels with flat fading, the spatially equalized and decoupled mul...

Precoding for transmission over channels with interference known at the transmitter is reviewed. In contrast to what is usually discussed in literature, precoding employing higher-dimensional lattice quantization for generating the transmit signal is assessed. It is shown that thereby the gap between low-complexity schemes using scalar modulo reductions and theoretical asymptotic results assumi...

—This paper studies the two-hop co-located transmission architecture that incorporates simultaneous wireless information and power transfer in radio relay networks. Joint robust precoding design of the information and power transfer that can minimize the overall relays’ power consumption while satisfying our predefined quality-of-service and energy-harvest requirements is provided. By using Se...

A powerful HARQ-based linear precoding scheme is proposed to utilize the flexibility of post-combining HARQ strategy in MIMO communications systems. The scheme selects the appropriate symbols and transmit powers for each eigen-mode to acquire more performance gains. Simulation results show that the proposed scheme achieves about 5.5 dB signal-to-noise ratio gains over original spatial multiplex...