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On Capacities of the Two-User Union Channel with Complete Feedback

Zilin Jiang, Nikita Polyanskii, Ilya Vorobyev
2018 IEEE Transactions on Information Theory  
The exact values of the optimal symmetric rate point in the Cover--Leung capacity region of the two-user union channel with complete feedback were determined by Willems when the size of the input alphabet  ...  The proof hinges on the technical lemma that concerns the maximal joint entropy of two independent random variables in terms of their probability of equality.  ...  Acknowledgements This work was supported in part by the National Natural Science Foundation of China under the Grant nos. 11505098,  ... 
doi:10.1109/tit.2018.2889250 fatcat:fewk3vwy7zfmdjr7xemv4qhc7y

Multiple Access Channels With States Causally Known at Transmitters

Min Li, Osvaldo Simeone, Aylin Yener
2013 IEEE Transactions on Information Theory  
Specifically, it was proved that the capacity region of a two-user MAC with independent states, each known strictly causally to one encoder, can be enlarged by letting the encoders send compressed past  ...  Capacity results are then derived for a class of channels that include two-user modulo-additive state-dependent MACs.  ...  ACKNOWLEDGMENT The authors would like to thank the Associate Editor and the anonymous reviewers for their comments, which have improved the quality of the paper.  ... 
doi:10.1109/tit.2012.2229459 fatcat:ig44qgen55cslk4fue7u52qn6m

The capacity region of the discrete memoryless interference channel with strong interference (Corresp.)

M. Costa, A.E. Gamal
1987 IEEE Transactions on Information Theory  
A/~ruci -The capacity region of the discrete memoryless interference channel with strong interference is established.  ...  Although feedback is very common in practical channels, it is still only imperfectly understood and a large number of problems remain open on the capacity of channels with feedback.  ...  on the total capacity (sum of the rates of all the senders) of an m-user Gaussian multiple access channel in terms of the input covariance matrix.  ... 
doi:10.1109/tit.1987.1057340 fatcat:dvml6jvp4jhbxbnyx7wbsiizxy

Space Division Multiple Access With a Sum Feedback Rate Constraint

Kaibin Huang, Robert W. Heath, Jeffrey G. Andrews
2007 IEEE Transactions on Signal Processing  
The sum rate for channel state information (CSI) feedback, however, increases linearly with the number of users, reducing the effective uplink capacity.  ...  The key feature of the proposed approach is the use of feedback thresholds to select feedback users with large channel gains and small CSI quantization errors such that the sum feedback rate constraint  ...  First, a feedback threshold on all the users' channel power selects users with large channel gains for feedback.  ... 
doi:10.1109/tsp.2007.894245 fatcat:372ksnsfyjfh5ooqlvdhlm5qby

Binary fading interference channel with delayed feedback

Alireza Vahid, Mohammad Ali Maddah-Ali, A. Salman Avestimehr
2012 2012 IEEE International Symposium on Information Theory Proceedings  
In this paper, we study the capacity region of the two-user binary fading interference channel with delayed network state information at the transmitters and a noiseless output feedback link from each  ...  We also derive new outer-bounds on the capacity region of such network, and we show that the delay in learning network state information results in some loss in the capacity region.  ...  We studied the capacity region of the two-user binary fading interference channel with delayed network state information and output feedback.  ... 
doi:10.1109/isit.2012.6283624 dblp:conf/isit/VahidMA12 fatcat:uc65x35xazgodflvsi73c4zkye

The two-user broadcast packet erasure channel with feedback and memory

Michael Heindlmaier, Clemens Blochl
2014 2014 International Symposium on Network Coding (NetCod)  
The two-user broadcast erasure channel with feedback and memory is analyzed. It is shown that memory increases the capacity region for this scenario.  ...  Although these schemes do not achieve capacity, significant gains can be observed compared to the memoryless case.  ...  INTRODUCTION The memoryless broadcast erasure channel (BEC) with feedback (FB) is one of the examples in multiuser communication systems where the capacity region is known and feedback increases the capacity  ... 
doi:10.1109/netcod.2014.6892132 dblp:conf/netcod/HeindlmaierB14 fatcat:mxnwexjic5bydcfn3lcit36tdq

Capacity limits of MIMO channels

A. Goldsmith, S.A. Jafar, N. Jindal, S. Vishwanath
2003 IEEE Journal on Selected Areas in Communications  
We provide an overview of the extensive recent results on the Shannon capacity of single-user and multiuser multiple-input multiple-output (MIMO) channels.  ...  We then focus attention on the capacity region of the multiple-access channels (MACs) and the largest known achievable rate region for the broadcast channel.  ...  capacity of the MIMO BC for the two-user, , channel by Caire and Shamai [9] .  ... 
doi:10.1109/jsac.2003.810294 fatcat:bhfypf6q55babacntxohjerjiu

Feedback Capacity of the Gaussian Interference Channel to Within 2 Bits

Changho Suh, David N. C. Tse
2011 IEEE Transactions on Information Theory  
We characterize the capacity region to within 2 bits/s/Hz and the symmetric capacity to within 1 bit/s/Hz for the two-user Gaussian interference channel (IC) with feedback.  ...  One consequence of the result is that feedback provides multiplicative gain at high signal-to-noise ratio: the gain becomes arbitrarily large for certain channel parameters.  ...  CONCLUSION We have established the feedback capacity region to within 2 bits/s/Hz/user and the symmetric capacity to within 1 bit/s/Hz/user universally for the two-user Gaussian IC with feedback.  ... 
doi:10.1109/tit.2011.2119990 fatcat:m4gsuvsxvjgyxixh6yaovsnvmu

Multiuser Broadcast Erasure Channel With Feedback—Capacity and Algorithms

Marios Gatzianas, Leonidas Georgiadis, Leandros Tassiulas
2013 IEEE Transactions on Information Theory  
We consider the N-user broadcast erasure channel with N unicast sessions (one for each user) where receiver feedback is regularly sent to the transmitter in the form of ACK/NACK messages.  ...  under certain conditions on channel statistics, assuming that instantaneous feedback is known to all users.  ...  Theorem 5: CODE2 achieves the capacity outer bound of C out , assuming complete feedback is known to all users.  ... 
doi:10.1109/tit.2013.2265692 fatcat:bchdlbgngnfjtounoid5vyuuja

Isotropic Fading Vector Broadcast Channels: The Scalar Upper Bound and Loss in Degrees of Freedom

S.A. Jafar, A.J. Goldsmith
2005 IEEE Transactions on Information Theory  
fading vector broadcast channels, and determine the capacity region of a fading vector Gaussian broadcast channel with channel magnitude feedback.  ...  We propose a scalar upper bound on the capacity region of the isotropic fading vector broadcast channel in terms of the capacity region of a scalar fading broadcast channel.  ...  Our thanks are also due to the anonymous reviewers and the Associate Editor for thorough reviews and for providing valuable comments and suggestions that significantly improved this paper.  ... 
doi:10.1109/tit.2004.842621 fatcat:eavjyjq56rcslkltycmaf7z45a

Multiuser Scheduling in a Markov-Modeled Downlink Using Randomly Delayed ARQ Feedback

Sugumar Murugesan, Philip Schniter, Ness B. Shroff
2012 IEEE Transactions on Information Theory  
In our setting, the channel between the base station and each user is modeled by a two-state Markov chain and the scheduled user sends back an ARQ feedback signal that arrives at the scheduler with a random  ...  For the case of two users in the system, we show that a greedy policy is sum throughput optimal for any distribution on the ARQ feedback delay.  ...  Hence, the greedy policy is optimal in the genie-aided system. With this insight, we now report our result on the sum capacity of the original downlink with two users.  ... 
doi:10.1109/tit.2011.2173717 fatcat:arwv6wg5v5c6zc3qkd6ctppo3e

On the Capacity and Design of Limited Feedback Multiuser MIMO Uplinks [article]

Il Han Kim, David J. Love
2008 arXiv   pre-print
Even with a small number of feedback bits, the performance of the proposed system is close to an optimal solution with the full feedback.  ...  This capacity gain can often be leveraged by utilizing channel state information at the transmitter and the receiver. Users make use of this channel state information for transmit signal adaptation.  ...  We can show that this fixed capacity polyhedron is closed and that the union of these polyhedrons is also closed. This completes the proof.  ... 
arXiv:0802.3253v1 fatcat:7y7pfwi3bve5zcdtexswrpwr4u

Too Much Mobility Limits the Capacity of Wireless Ad Hoc Networks

S.A. Jafar
2005 IEEE Transactions on Information Theory  
Assuming that the users' channels are identically distributed we determine the capacity region of this ad-hoc network for any partition of the users into transmitters and receivers.  ...  of additive noise [2] [3] there is no capacity benefit from increasing the number of transmit antennas beyond the channel coherence time Ì .  ...  Definition 3: [Feedback-Free Capacity Region ] We define the feedback-free capacity region as the convex hull of the union of the configuration capacity regions over all configurations: ¸co ÌÜ ÊÜ ´Ì Ü  ... 
doi:10.1109/tit.2005.856965 fatcat:hm33qskiufeixmcoifmhtyjili

On the Capacity and Design of Limited Feedback Multiuser MIMO Uplinks

Il Han Kim, David J. Love
2008 IEEE Transactions on Information Theory  
Even with a small number of feedback bits, the performance of the proposed system is close to an optimal solution with the full feedback.  ...  This capacity gain can often be leveraged by utilizing channel state information at the transmitter and the receiver. Users make use of this channel state information for transmit signal adaptation.  ...  We can show that this fixed capacity polyhedron is closed and that the union of these polyhedrons is also closed. This completes the proof.  ... 
doi:10.1109/tit.2008.928997 fatcat:7c6vbg4v3zdnbdxsas6dvybebi

Achieving the Capacity Region Boundary of Fading CDMA Channels via Generalized Iterative Waterfilling

Onur Kaya, Sennur Ulukus
2006 IEEE Transactions on Wireless Communications  
We then investigate the effects of limited feedback on the capacity region, and demonstrate that a good power control policy may require only a very low rate feedback.  ...  channel with perfect channel state information.  ...  We then investigated the effect of limited feedback on the capacity region of the CDMA channel.  ... 
doi:10.1109/twc.2006.04785 fatcat:u5paccmw7zhftdgtgywil6qnaa
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