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Underlining the viability of multiuser (MU) MIMO for future wireless communications as long term evolution (LTE), we propose in this paper a precoding strategy based on the low resolution LTE precoders which necessitates 2 bits feedback from the user equipment (UE). The proposed strategy encompasses geometrical interference alignment at eNodeB (LTE notation for base station) followed by the exploitation...
In this paper, our aim is to use a Kerdock codebook-based precoding scheme for a multi-user MIMO broadcast channel with channel state information at the base station and limited feedback. The main reason for applying a Kerdock code in place of optimal precoding is to reduce VLSI implementation complexity. The proposed scheme exploits the scheduling and precoding methods with a view to maximizing system...
In this paper, our purpose is to use the maximal signal-to-jamming-and noise ratio (SJNR) criterion to design a Grassmannian codebook for a precoding scheme in a multi-user MIMO broadcast channel. The proposed approach includes two schemes. In the first, we assume that the channel information at the base station is available. The second scheme is under limited feedback. Both schemes aim to reduce...
In this paper, we propose a novel transmit preprocessing scheme using Channel Selection (CS) to jointly design PreRake and Precoding for multiple-input multiple-output Ultra-Wideband (MIMO-UWB) communications. The PreRake technique is implemented to exploit the advantage of multipath diversity and can achieve spatial multiplexing based on our proposed CS. The combination of CS and PreRake transforms...
In the downlink of multiuser MIMO (MU-MIMO) systems, the co-channel interference (CCI) and noise are two major impairments. Maximizing signal to leakage plus noise ratio (SLNR) is a good criterion for the design of precoders since it making a balance between eliminating the CCI and noise. In this text, we propose a channel adaptive power allocation scheme based on SLNR precoding. Simulation results...
Currently and thereafter, evaluations and consensusbuilding process will be performed for the 4G candidates from ITU-R membership, standards organizations, and other external evaluation groups. Among them, the Chinese Evaluation Group (ChEG) is also responsible for submitting the evaluation report to ITU-R. This paper addresses the evaluation methodology and relevant activities. Descriptions to the...
This paper considers maximizing the network-wide minimum supported rate in the downlink of a two-cell system with symmetric channel statistics, where each base station (BS) is endowed with multiple antennas. This is done for different levels of cell cooperation. At one extreme, we consider single cell processing where the BS is oblivious to interference created at the other cell. At the other, we...
We address the problem of a multi-user relay network, where multiple single-antenna node pairs want to exchange information by using a multiple antenna relay node. Due to the half-duplex constraint of the relay, the exchange of information takes place in two steps. In the first step, the nodes transmit their data to the relay, while in the second step, the relay is broadcasting the data by using linear...
In this paper, we concentrate on the downlink precoding scheme for the multi-user MIMO system with 4 × 4 Quasi-orthogonal space time block codes (QSTBC). An iterative precoding scheme based on the signal-to-leakage-noise ratio (SLNR) maximization is proposed. This precoding scheme is general to different QSTBCs. By choosing the complex scalars properly, a simple solution of the optimization problem...
This paper addresses the robust transceiver optimization in multiple-input and multiple-output cognitive radio network, where primary users (PUs) and secondary users (SUs) coexist in the same spectrum band. In the design of cognitive system, the performance degradation perceived by PU should be strictly restricted even with imperfect channel state information (CSI) at cognitive transmitter and receivers...
In this paper, we deal with user scheduling algorithms for a codebook based precoding of a multiuser multiple-input multiple-output (MIMO) downlink system considered in IEEE 802.16m and 3rd Generation Partnership Project Long-Term Evolution (3GPP LTE) standardization. We especially focus on per-user unitary rate control (PU2RC) and semi-orthogonal user selection schemes. Also, we examine the disadvantage...
Network MIMO, in which base stations cooperate and coordinate through a centralized design, is an attractive technology that promises higher spectral efficiency and lower inter-cell interference. However, such performance gain comes at the cost of extensive exchange of signal information (SI), channel state information (CSI), and coordinated precoding information over backhaul links. In this paper,...
A new joint transceiver design with the interference alignment technique for K-user MIMO interference channel without the need of symbol extension is proposed with arbitary antenna configuration in transmitters and receivers. The sum-MSE and weighted-sum-MSE act as the cost function. Convergence of the proposed algorithm has been confirmed. Compared to existing iterative schemes, the proposed algorithm...
Precoding and decoding for Multiuser MIMO has drawn many researchers' attention. Block Diagonolization (BD) is a competition algorithm for its low-complexity. BD algorithms usually uses the Zero-Forcing criterion, so the performance degrades especially when the noise is strong. The consideration of noise leads to the MMSE criterion. But for multiuser MIMO, there are no methods implementing MMSE both...
In wireless cellular systems, cell edge users can only achieve far less capacity than cell center uses because of low receive signal power and strong inter-cell interference. Base station joint transmission has been proven to be an effective method to mitigate this effect. In this paper, we propose a novel precoding scheme for non-coherent joint transmission where both base stations and mobile stations...
To alleviate the interference while lowering the hardware cost such as the RF chains associated with antennas in the downlink of multiuser multi-input multi-output (MIMO) systems with limited feedback, this paper presents a simple, yet effective approach for joint precoding and transmit antenna selection with the assistance of the genetic algorithm (GA). To overcome the enormous amount of search called...
In this paper, we study the quantized precoding strategy selection for multiple-input multiple-output (MIMO) multiple access channels (MAC) in cognitive radio (CR) networks through a game-theoretic perspective. Since the secondary users in such system are difficult to be coordinated by a centralized authority, they are noncooperative and attempt to maximize their own payoffs selfishly in a distributed...
We investigate enhanced downlink multiuser multiple input multiple output (MU-MIMO) transmission schemes for 3GPP LTE-Advanced based on system level simulations. As compared to Rel. 8 LTE single user MIMO (SU-MIMO), MU-MIMO has the potential to better exploit the spatial dimension of MIMO channels in some scenarios. Although Rel. 8 LTE defines a simple MU-MIMO mode, more advanced MU-MIMO techniques...
This paper presents a new peak-to-average power ratio (PAPR) reduction method based on clipping and filtering for precoded orthogonal frequency division multiplexing (OFDM)-multiple-input multiple-output (MIMO) transmission. While the conventional clipping and filtering method adds roughly the same interference power to each of the transmission streams, the proposed method restricts the interference...
A novel linear precoding scheme is proposed for the downlink of multiuser multiple input multiple output (MIMO) systems, that offers enhanced data throughput compared to conventional precoding. The proposed technique is based on the fact that part of the instantaneous multiple access interference (MAI) inherent in a multiuser MIMO system adds constructively to the useful signal. It utilises this concept...
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