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Via multiterminal information theory, we present fundamental rate delay tradeoffs that delay mitigating codes must have when utilized over multipath routed and network coded networks. We formulate plotting the rate delay tradeoff as a calculus problem on a capacity region of a related abstracted broadcast channel. This calculus problem simplifies to an(More)
While its performance in the Gaussian, infinite block length, and loopless factor graph cases are well understood, the breakthrough applications of the belief propagation algorithm to the decoding of turbo and LDPC codes involve finite block lengths, finite alphabets, and factor graphs with loops. It has been shown in these instances that the stationary(More)
Many previous attempts at analyzing the convergence behavior of turbo and iterative decoding, such as EXIT style analysis [1] and density evolution [2], ultimately appeal to results which become valid only when the block length grows rather large, while still other attempts, such as connections to factor graphs [3] and belief propagation [4], have been(More)
The identification of individuals by the sound of their voices, a fairly straightforward task for humans, has proven to be quite difficult to achieve in a robust way computationally. The majority of past work in speaker (talker) identification has focused on the single speaker case, but these systems are easily confounded by most real-world settings where(More)
Channel shortening is often employed as a means of mitigating intersymbol and intercarrier interference (ISI and ICI) in systems using multicarrier modulation. The Multicarrier Equalization by Restoration of RedundancY (MERRY) algorithm has previously been shown to blindly and adaptively shorten a channel to the length of the guard interval in a(More)
The turbo decoder was not originally introduced as a solution to an optimization problem, which has impeded attempts to explain its excellent performance. Here it is shown, that the turbo decoder is an iterative method seeking a solution to an intuitively pleasing constrained optimization problem. In particular, the turbo decoder seeks the(More)
A computational technique for determining rate regions for networks and multilevel diversity coding systems based on inner and outer bounds for the region of entropic vectors is discussed. The expression to get rate region in terms of region of entropic vectors is attributed to Yeung and Zhang. An inner bound based on binary representable matroids is(More)
A new computational technique is presented for determining rate regions for coded networks. The technique directly manipulates the extreme ray representation of inner and outer bounds for the region of entropic vectors. We use new inner bounds on region of entropic vectors based on conic hull of ranks of representable matroids. In particular, the(More)
For the resource allocation problem in a multiuser OFDMA system, we propose an interactive communication scheme between the base station and the users with the assumption that this system utilizes a rateless code for data transmission. We describe the problem of minimizing the overhead measured in the number of bits that must be exchanged required by the(More)