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Interference Alignment and Degrees of Freedom of the $K$-User Interference Channel
TLDR
For the fully connected K user wireless interference channel where the channel coefficients are time-varying and are drawn from a continuous distribution, the sum capacity is characterized as C(SNR)=K/2log (SNR)+o(log( SNR), which almost surely has K/2 degrees of freedom.
A Distributed Numerical Approach to Interference Alignment and Applications to Wireless Interference Networks
TLDR
Examples of iterative algorithms that utilize the reciprocity of wireless networks to achieve interference alignment with only local channel knowledge at each node are provided, providing numerical insights into the feasibility of interference alignment that are not yet available in theory.
Breaking Spectrum Gridlock With Cognitive Radios: An Information Theoretic Perspective
TLDR
This information-theoretic survey provides guidelines for the spectral efficiency gains possible through cognitive radios, as well as practical design ideas to mitigate the coexistence challenges in today's crowded spectrum.
Approaching the Capacity of Wireless Networks through Distributed Interference Alignment
TLDR
Examples of iterative algorithms that utilize the reciprocity of wireless networks to achieve interference alignment with only local channel knowledge at each node are provided, providing numerical insights into the feasibility of interference alignment that are not yet available in theory.
Capacity limits of MIMO channels
TLDR
An overview of the extensive results on the Shannon capacity of single-user and multiuser multiple-input multiple-output (MIMO) channels is provided and it is shown that the capacity region of the MIMO multiple access and the largest known achievable rate region (called the dirty-paper region) for the M IMO broadcast channel are intimately related via a duality transformation.
Interference Alignment and Spatial Degrees of Freedom for the K User Interference Channel
  • V. Cadambe, S. Jafar
  • Computer Science
    IEEE International Conference on Communications
  • 3 July 2007
We show that the sum capacity of the K user frequency selective (or time-varying) interference channel is C(SNR) = (K/2) log(SNR) +o(log(SNR)) meaning that the channel has a total of K/2 degrees of
On Feasibility of Interference Alignment in MIMO Interference Networks
TLDR
This work explores the feasibility of interference alignment in signal vector space-based only on beamforming-for K-user MIMO interference channels and shows that the connection between feasible and proper systems can be further strengthened by including standard information theoretic outer bounds in the feasibility analysis.
The Capacity of Private Information Retrieval
TLDR
A remarkable feature of the capacity achieving scheme is that if the authors eliminate any subset of messages (by setting the message symbols to zero), the resulting scheme also achieves the PIR capacity for the remaining subset of message.
Sum power iterative water-filling for multi-antenna Gaussian broadcast channels
TLDR
A "duality" is used to transform the problem of maximizing sum rate on a multiple-antenna downlink into a convex multiple access problem, and then a simple and fast iterative algorithm is obtained that gives the optimum transmission policies.
Degrees of Freedom Region of the MIMO $X$ Channel
  • S. Jafar, S. Shamai
  • Computer Science
    IEEE Transactions on Information Theory
  • 21 July 2006
We provide achievability as well as converse results for the degrees of freedom region of a multiple-input multiple-output (MIMO) X channel, i.e., a system with two transmitters, two receivers, each
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