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Spatially Sparse Precoding in Millimeter Wave MIMO Systems
This paper considers transmit precoding and receiver combining in mmWave systems with large antenna arrays and develops algorithms that accurately approximate optimal unconstrained precoders and combiners such that they can be implemented in low-cost RF hardware. Expand
Channel Estimation and Hybrid Precoding for Millimeter Wave Cellular Systems
An adaptive algorithm to estimate the mmWave channel parameters that exploits the poor scattering nature of the channel is developed and a new hybrid analog/digital precoding algorithm is proposed that overcomes the hardware constraints on the analog-only beamforming, and approaches the performance of digital solutions. Expand
Low complexity precoding for large millimeter wave MIMO systems
A precoding algorithm is developed that approximates the optimal unconstrained precoder using a low dimensional basis representation that can be efficiently implemented in RF hardware and allows mmWave systems to approach waterfilling capacity. Expand
The capacity optimality of beam steering in large millimeter wave MIMO systems
This paper considers both beamforming and multi-stream precoding in single user systems with large mmWave antenna arrays at both transmitter and receiver and shows that the unconstrained capacity-achieving precoding solutions converge to simple beam steering solutions. Expand
Interference Alignment with Analog Channel State Feedback
  • Omar El Ayach, R. Heath
  • Computer Science, Mathematics
  • IEEE Transactions on Wireless Communications
  • 13 October 2010
It is shown that the full multiplexing gain observed with perfect channel knowledge is preserved by analog feedback and that the mean loss in sum rate is bounded by a constant when signal-to-noise ratio is comparable in both forward and feedback channels. Expand
The Feasibility of Interference Alignment Over Measured MIMO-OFDM Channels
This paper presents the first experimental study of IA in measured multiple-input-multiple-output orthogonal frequency-division-multiplexing (MIMO-OFDM) interference channels and shows that IA achieves the claimed scaling factors, or degrees of freedom, in several measured channel settings for a three-user two-antenna-per-node setup. Expand
The practical challenges of interference alignment
An overview of the concept of interference alignment as well as an assessment of practical issues including performance in realistic propagation environments, the role of channel state information at the transmitter, and the practicality of interference aligning in large networks are provided. Expand
Coverage and capacity in mmWave cellular systems
It is shown that coverage in mmWave systems can rival or even exceed coverage in microwave systems assuming that the link budgets promised by existing mmWave system designs are in fact achieved and this comparable coverage translates into a superior average rate performance for mmWave Systems as a result of the larger bandwidth available for transmission. Expand
Multimode precoding in millimeter wave MIMO transmitters with multiple antenna sub-arrays
An iterative precoding algorithm for a practical mmWave transmitter architecture in which all precoding is done in the analog domain is proposed, and the algorithm allows the mmWave system to adapt the rank of its transmission in response to varying propagation conditions. Expand
On the Overhead of Interference Alignment: Training, Feedback, and Cooperation
This paper studies the performance of IA in multiple-input multiple-output systems where channel knowledge is acquired through training and analog feedback, and designs the training and feedback system to maximize IA's effective sum-rate: a non-asymptotic performance metric that accounts for estimation error,Training and feedback overhead, and channel selectivity. Expand