IEEE Transactions on Information Theory

Multiple description source coding concerns situations in which the transmission of the source information is distributed over two data streams at rates R₁ and R₂, respectively. When both data streams are received, the decoder uses the combined data at ...

Transmission algorithms are introduced for use in a single-hop packet switching system with nonuniform traffic and with propagation delay that Is large relative to the packet transmission time. The traffic model allows arbitrary traffic streams subject ...

We construct new self-dual and isodual codes over the integers module 4. The binary images of these codes under the Gray map are nonlinear, but formally self-dual. The construction involves Hensel lifting of binary cyclic codes. Quaternary quadratic ...

We give the full automorphism groups as groups of semiaffine transformations, of the extended generalized quadratic residue codes. We also present a proof of the Gleason-Prange theorem for the extended generalized quadratic residue codes that relies ...

For (n, q)=1 V a q^m-ary cyclic code of length n and with generator polynomial g(x), we show that there exists a basis for F(q^m) over F_q with respect to which the q-ary image of V is cyclic, if and only if: (i) g(x) is over F_q; or (ii) g(x)=g₀(x)(x-&...

A new class of q-ary sequences, called interleaved sequence, is introduced. Their periods, shift equivalence, linear spans, and autocorrelation functions are derived. The interleaved sequences include a large number of popular sequences, such as ...

In a Diversity Coding System, an information source is encoded by a number of encoders. There are a number of decoders, each of which can access a certain subset of the encoders. We study a diversity coding problem in which there are two levels of ...

Large families of binary sequences with low correlation values and large linear span are critical for spread-spectrum communication systems. The author describes a method for constructing such families from families of homogeneous functions over finite ...

The minimum support weight, d_r(C), of a linear code C over GF(q) is the minimal size of the support of an r-dimensional subcode of C. A number of bounds on d_r(C) are derived, generalizing the Plotkin bound and the Griesmer bound, as well as giving two ...

A Markovian technique is described to calculate the exact performance of the Viterbi algorithm used as either a channel decoder or a source encoder for a convolutional code. The probability of information bit error and the expected Hamming distortion ...

Three new constructions for families of cyclic constant weight codes are presented. All are asymptotically optimum in the sense that in each case, as the length of the sequences within the family approaches infinity, the ratio of family size to the ...

We present an analog of the well-known Weil-Carlitz-Uchiyama (1948, 1957) upper bound for exponential sums over finite fields for exponential sums over Galois rings. Some examples are given where the bound is tight. The bound has immediate application ...

We define and estimate the threshold probability θ of a linear code, using a theorem of Margulis (1974) originally conceived for the study of the probability of disconnecting a graph. We then apply this concept to the study of the erasure and Z-...

Consider the parsing algorithm developed by Lempel and Ziv (1978) that partitions a sequence of length n into variable phrases (blocks) such that a new block is the shortest substring not seen in the past as a phrase. In practice, the following ...

We consider the convergence analysis of the sign algorithm for adaptive filtering when the input processes are uncorrelated and Gaussian and a fixed step size μ>0 is used. Exact recursive equations for the covariance matrix of the deviation error ...

It is shown that, when the input signal-to-interference ratio (SIR) is small, a biased nonlinearity that has a dead zone below some threshold value can provide a large enhancement in output SIR and signal-to-interference-plus-intermodulation ratio (...

Kumar and Moreno (see ibid., vol.37, no.3, p.603, 1991) presented a new family of nonbinary sequences which has not only good periodic correlation properties but also the largest family size. First, the unbalanced properties for Kumar-Moreno sequences ...

Unequal error protection (UEP) codes find applications in broadcast channels, as well as in other digital communication systems, where messages have different degrees of importance. Binary linear UEP (LUEP) codes combined with a Gray mapped QPSK signal ...

Let n₄(k, d) be the smallest integer n, such that a quaternary linear [n, k, d; 4]-code exists. It is proved that n₄ (5, 20)=30, n₄(5, 42)⩾59, n₄(5, 45)⩾63, n₄(5, 64)⩾88, n₄(5, 80)=109, n₄(5, 140)⩾189, n₄(5, 143)⩾193, n₄ (5, 168)⩾...

Shows that for any sequence ρ(n)=o(n) and any sequence of prefix codes, there is a B-process of entropy arbitrarily close to the maximum possible entropy for which the expected redundancy is at least as large as ρ(n) for infinitely many n. This ...

Constant false alarm rate detection is considered in a decentralized, two-sensor context. Cases with observations which are dependent from sensor to sensor are investigated, for which results have been lacking. The in-phase and quadrature components of ...

Distributed signal detection schemes have received significant attention, but most research has focused on cases with independent observations at the different sensors. Cases with dependent narrowband signals, which are of practical interest in ...

Three new techniques are proposed for constructing a class of codes that extends the protection provided by previous single error correcting (SEC)-double error detecting (DED)-single byte error detecting (SBD) codes. The proposed codes are systematic ...

We propose an algorithm for bounded minimum distance decoding of (partial) unit memory codes up to half the “designed” extended row distance. It makes use of a reduced trellis with the nodes found by bounded minimum distance decoding of the ...

At present, optimal coding for a noiseless digital channel with digits of unequal cost requires solving a large linear programming problem. Much simpler procedures give codes, resembling Shannon's (1948) and Huffman's, that are found close to optimal in ...

The asymptotic relative efficiency (ARE) of two centralized detection schemes has proved useful in large-sample-size and weak-signal performance analysis. In the present paper ARE is applied to some distributed detection cases which use counting fusion ...

The Neyman-Pearson performance of a distributed detection system is considered wherein n independent and identically distributed observations are quantized locally into M-ary messages and transmitted to a fusion center. Under fairly general assumptions, ...

Considers the problem of deciding between M signals that are observed through an unknown FIR system (channel). The authors suggest a generalized likelihood ratio test, and develop an upper bound on the detection performance under the worst possible ...

The multivariate complex normal distribution usually employed in the literature is a special case since certain restrictions have been imposed on the covariances of the real and imaginary parts of its variables. A more general distribution is proposed ...

Presents an improvement to Demho's (1988) lower bound on the smallest eigenvalue of a Hermitian positive-definite matrix. Unlike Dembo's bound the improved bound is always positive