A Survey of Results for Deletion Channels and Related Synchronization Channels
SWAT '08 Proceedings of the 11th Scandinavian workshop on Algorithm Theory
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ACM SIGCOMM Computer Communication Review
Capacity region of the finite-state multiple-access channel with and without feedback
IEEE Transactions on Information Theory
Reliable and secure broadcast communication over resource constrained systems
Proceedings of the Fourth International ICST Conference on Performance Evaluation Methodologies and Tools
A subsequence-histogram method for generic vocabulary recognition over deletion channels
ISIT'09 Proceedings of the 2009 IEEE international conference on Symposium on Information Theory - Volume 4
Feedback capacity of a class of symmetric finite-state Markov channels
Allerton'09 Proceedings of the 47th annual Allerton conference on Communication, control, and computing
IEEE Transactions on Communications
Directly lower bounding the information capacity for channels with I.I.D.deletions and duplications
IEEE Transactions on Information Theory
Codes for deletion and insertion channels with segmented errors
IEEE Transactions on Information Theory
Hi-index | 755.02 |
We study information transmission through a finite buffer queue. We model the channel as a finite-state channel whose state is given by the buffer occupancy upon packet arrival; a loss occurs when a packet arrives to a full queue. We study this problem in two contexts: one where the state of the buffer is known at the receiver, and the other where it is unknown. In the former case, we show that the capacity of the channel depends on the long-term loss probability of the buffer. Thus, even though the channel itself has memory, the capacity depends only on the stationary loss probability of the buffer. The main focus of this correspondence is on the latter case. When the receiver does not know the buffer state, this leads to the study of deletion channels, where symbols are randomly dropped and a subsequence of the transmitted symbols is received. In deletion channels, unlike erasure channels, there is no side-information about which symbols are dropped. We study the achievable rate for deletion channels, and focus our attention on simple (mismatched) decoding schemes. We show that even with simple decoding schemes, with independent and identically distributed (i.i.d.) input codebooks, the achievable rate in deletion channels differs from that of erasure channels by at most H0(pd)-pd logK/(K-1) bits, for pd<1-K-1, where p d is the deletion probability, K is the alphabet size, and H 0(middot) is the binary entropy function. Therefore, the difference in transmission rates between the erasure and deletion channels is not large for reasonable alphabet sizes. We also develop sharper lower bounds with the simple decoding framework for the deletion channel by analyzing it for Markovian codebooks. Here, it is shown that the difference between the deletion and erasure capacities is even smaller than that with i.i.d. input codebooks and for a larger range of deletion probabilities. We also examine - - the noisy deletion channel where a deletion channel is cascaded with a symmetric discrete memoryless channel (DMC). We derive a single letter expression for an achievable rate for such channels. For the binary case, we show that this result simplifies to max(0,1-[H0(thetas)+thetasH0(p e)]) where pe is the cross-over probability for the binary symmetric channel