n-Channel Multiple Descriptions: Theory and Constructions
نویسندگان
چکیده
We present new achievable rate regions and code constructions for the symmetric n-channel Multiple Descriptions (MD) coding problem [1] for n > 2. Our approach is inspired by unexplored connections between MD and the problem of distributed source coding [2, 3]. For illustrative clarity, we restrict our focus to the important special case relating to (n, k) source-channel erasure codes [4]. This involves n encodings of a source with the goal of maximizing its reconstruction fidelity with the availability of any k of them, while strictly improving this reconstruction fidelity with the availability of more than k descriptions. We describe the underlying information-theoretic framework, and then formulate practical constructions based on scalar quantizers and linear channel codes for the n=3 case to illustrate our concepts.
منابع مشابه
Space-time codes achieving the DMD tradeoff of the MIMO-ARQ channel
For the quasi-static, Rayleigh-fading multiple-input multiple-output (MIMO) channel with transmit and receive antennas, Zheng and Tse showed that there exists a fundamental tradeoff between diversity and spatial-multiplexing gains, referred to as the diversity–multiplexing gain (D-MG) tradeoff. Subsequently, El Gamal, Caire, and Damen considered signaling across the same channel using an -round...
متن کاملConstructions of protocol sequences for multiple access collision channel without feedback
Constructions of protocol sequences for multiple-access collision channel without feedback are given. These constructions are the extensions of those described by A, GyiiriI, and Massey. If the basic code in their constructions, a Reed-Solomon code, is replaced by a BCH code then the resulting protocol sequences have the feature that, for a given sum rate, the ratio of the total user population...
متن کاملSmall Pseudo-random Families of Matrices: Derandomizing Approximate Quantum Encryption
A quantum encryption scheme (also called private quantum channel, or state randomization protocol) is a one-time pad for quantum messages. If two parties share a classical random string, one of them can transmit a quantum state to the other so that an eavesdropper gets little or no information about the state being transmitted. Perfect encryption schemes leak no information at all about the mes...
متن کاملCoding for a Multiple Access OR Channel: a Survey
The signature coding for M active users out of T total users over a multiple access OR channel is considered. The mathematical problem is equivalent to the M -coverfree problem of extremal set theory. We survey the upper and lower bounds on the minimal code word length n(T,M), and present some code constructions. According to the current state of the theory, for 1 M T 1 2 M2 logM log T ≤ n(T,M)...
متن کاملError and erasure control (d, k) block codes
New combinatorial and algebraic techniques are presented for systematically constructing different (d,k) block codes capable of detecting and correcting single bit-errors, single-peak shift-errors, double adjacent-errors and multiple adjacent erasures. Constructions utilizing channel side information, such as the magnetic recording ternary channel output string, or erasures, do not impose any r...
متن کامل