—An information-theoretic framework for unequal error protection is developed in terms of the exponential error bounds. The fundamental difference between the bit-wise and message-wise unequal error protection (UEP) is demonstrated, for fixed-length block codes on discrete memoryless channels (DMCs) without feedback. Effect of feedback is investigated via… (More)
—A lower bound bound is established on the error probability of fixed-length block-coding systems with finite memory feedback, which can be described in terms of a time dependent finite state machine. It is shown that the reliability function of such coding systems over discrete memoryless channels is upper-bounded by the sphere-packing exponent.
Schalkwijk and Kailath (1966) developed a class of block codes for Gaussian channels with ideal feedback for which the probability of decoding error decays doubly exponentially in block length for rates below capacity. This well-known but surprising result is explained and simply derived here in terms of a result by Elias (1956) concerning the minimum… (More)
— Variable-length block-coding schemes are investigated for discrete memoryless channels (DMC) with perfect feedback under cost constraints. Upper and lower bounds are found for the minimum achievable probability of decoding error Pe,min as a function of transmission rate R, cost constraint P, and expected block length τ. For given P and R, the lower and… (More)
— Fixed length block codes on discrete memoryless channels with feedback are considered for errors and erasures decoding. Upper and lower bounds are derived for the error exponent in terms of the rate and the erasure exponents. In addition the converse result of Burnashev for variable length block codes is extended to include list decoding.
The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Abstract The bit-wise unequal error protection problem, for the case when the number of groups of bits ℓ is fixed, is considered for variable length block codes with feedback. An encoding scheme based on fixed length block codes with… (More)
A new technique is proposed for upper bounding the error probability of fixed length block codes with feedback. Error analysis is inspired by Gallager's error analysis for block codes without feedback. Zigangirov-D'yachkov (2-D) encoding scheme is analyzed with the technique on binary input channels and k-ary symmetric channels. A strict improvement is… (More)
—Various formulations are considered where some information is more important than other and needs better protection. Our information theoretic framework in terms of exponential error bounds provides some fundamental limits and optimal strategies for such problems of unequal error protection. Even for data-rates approaching the channel capacity, it shows… (More)
— 1 Various scenarios are considered where some information is more important than other and needs better protection. A general theoretical framework for unequal error protection is developed in terms of exponential error bounds. It provides some fundamental limits and optimal strategies for such problems. A new class of problems called message-wise unequal… (More)