# IEEE Transactions on Information Theory

## Filter Results

Displaying Results 1 - 25 of 25
• ### Mutual information of the white Gaussian channel with and without feedback

Publication Year: 1971, Page(s):368 - 371
Cited by:  Papers (79)
| | PDF (497 KB)

The following model for the white Gaussian channel with or without feedback is considered: $$Y(t) = \int_o ^{t} \phi (s, Y_o ^{s} ,m) ds + W(t)$$ where<tex>m</tex>denotes the message,<tex>Y(t)</tex>denotes the channel output at time<tex>t</tex>,<tex>Y_o ^ {t}</tex>denotes the sample path<tex>Y(\theta), 0 \leq \theta ... View full abstract»

• ### Capacity of a continuous memoryless channel with feedback

Publication Year: 1971, Page(s):372 - 378
Cited by:  Papers (26)
| | PDF (1024 KB)

Shannon showed that the capacity of a discrete memoryless channel can not be increased by noiseless feedback. It has been conjectured that this should be true for a continuous memoryless channel, provided such a channel is appropriately defined. We precisely define such a channel from two mathematically different points of view and rigorously prove that its capacity can not be increased by feedbac... View full abstract»

• ### Channels with asymptotically decreasing memory and anticipation

Publication Year: 1971, Page(s):379 - 385
Cited by:  Papers (16)
| | PDF (975 KB)

A definition for channels with asymptotically decreasing memory and anticipation is given. The relation to indecomposable finite-state channels and to a certain class of infinite-state channels is established. It is shown that for channels with asymptotically decreasing memory and anticipation every ergodic input source is admissible and that the coding theorem holds. View full abstract»

• ### Comparison of line-by-line and two-dimensional encoding of random images

Publication Year: 1971, Page(s):386 - 398
Cited by:  Papers (36)
| | PDF (1718 KB)

Most methods of encoding images require complicated implementation. Thus it is of interest to compare the transmission rates that can be achieved by classes of encoding methods of different complexity. We consider two classes of encoding operations. The first class allows any possible operation on the two-dimensional image source output. The second class allows only certain restricted operations o... View full abstract»

• ### Detectors, bandpass nonlinearities, and their optimization: Inversion of the Chebyshev transform

Publication Year: 1971, Page(s):398 - 404
Cited by:  Papers (85)  |  Patents (2)
| | PDF (1051 KB)

From the voltage-response characteristic of a memoryless nonlinearity the output amplitude in any harmonic zone is easily found as a function of the amplitude of a narrow-band input, but no general method has been known for inverting this (Chebyshev) transformation. The inversion is of interest because the best detector, bandpass non-linearity, or harmonic generator for various purposes, e.g., max... View full abstract»

• ### Signal detection in Gaussian noise of unknown level: An invariance application

Publication Year: 1971, Page(s):404 - 411
Cited by:  Papers (84)
| | PDF (858 KB)

The concept of invariance in hypothesis testing is brought to bear on the problem of detecting signals of known form and unknown energy in Gaussian noise of unknown level. The noise covariance function is assumed to be<tex>K(t,u) = \sigma^2 \pho(t,u)</tex>where<tex>\rho(t,u)</tex>is the known form of the covariance function and<tex>\sigma^2</tex>is the unknown l... View full abstract»

• ### Probability of error for binary permutation modulation on a fading Gaussian channel

Publication Year: 1971, Page(s):412 - 418
Cited by:  Papers (1)
| | PDF (585 KB)

The probability of error for binary permutation modulation with diversity on fading Gaussian channels is considered. Upper bounds on the probability of error are found in a simple manner. These bounds indicate that the probability of error decreases exponentially with increasing transmitter memory as long as the transmitter's rate is less than the ratio of average received signal power to noise po... View full abstract»

• ### Performance of coherent phase-shift-keyed systems with intersymbol interference

Publication Year: 1971, Page(s):418 - 431
Cited by:  Papers (34)
| | PDF (1217 KB)

In order to optimize the design of a coherent phase-shift-keyed (CPSK) system, it is necessary to estimate the amount of degradation produced by intersymbol interference. In this paper, an upper bound to the probability of error of<tex>m</tex>-ary CPSK systems is given when an ideal CPSK signal is passed through a linear time-invariant noisy filter. This bound can be used to estimate t... View full abstract»

• ### A Rapidly Converging First-Order Training Algorithm for an Adaptive Equalizer

Publication Year: 1971, Page(s):431 - 439
Cited by:  Papers (17)  |  Patents (4)
| | PDF (932 KB)

Currently used adaptive equalizers for the minimization of mean-square error in digital communications commonly employ a fixed-step-size gradient-search procedure. The algorithm to be described here employs variable step sizes designed to minimize the error after a specified number of iterations. The resultant convergence rate provides considerable improvement over the fixed-step-size approach. Bo... View full abstract»

• ### Nonparametric Bayes-risk estimation

Publication Year: 1971, Page(s):440 - 444
Cited by:  Papers (13)
| | PDF (764 KB)

Two nonparametric methods to estimate the Bayes risk using classified sample sets are described and compared. The first method uses the nearest neighbor error rate as an estimate to bound the Bayes risk. The second method estimates the Bayes decision regions by applying Parzen probability-density function estimates and counts errors made using these regions. This estimate is shown to be asymptotic... View full abstract»

• ### On the recognition of time-varying patterns using learning procedures

Publication Year: 1971, Page(s):445 - 452
Cited by:  Papers (3)
| | PDF (1077 KB)

Some recognizers for stochastic time-varying patterns with additive noise are studied. As in binary communication channels with fading, it is supposed that the fluctuation of a pattern (or signal) may be approximated by a stationary Gaussian autoregressive process with known parameters. Each measurement belongs to either of two classes: the pattern plus noise or noise alone. Under these assumption... View full abstract»

• ### Independence of measurements and the mean recognition accuracy

Publication Year: 1971, Page(s):452 - 456
Cited by:  Papers (34)
| | PDF (712 KB)

A situation of great practical importance in pattern recognition is the case where the designer has only a finite number of sample patterns from each class and the class-conditional density functions are not completely known. Recent results indicate that in this case the dimensionality of the pattern vector, i.e., the number of measurements, should not be arbitrarily increased, since above a certa... View full abstract»

• ### Decomposition of M-sequences and its applications

Publication Year: 1971, Page(s):457 - 463
Cited by:  Papers (8)
| | PDF (783 KB)

If the period of an<tex>m</tex>-sequence is<tex>2^t - 1 = n_1 n_2</tex>with<tex>n_1</tex>relative prime to<tex>n_2</tex>, then the vector<tex>m</tex>, a period of the<tex>m</tex>-sequence, can be decomposed in a special way into two subsequences of lengths<tex>n_1</tex>and<tex>n_2</tex>. The properties ... View full abstract»

• ### Inversionless decoding of binary BCH codes

Publication Year: 1971, Page(s):464 - 466
Cited by:  Papers (47)  |  Patents (9)
| | PDF (365 KB)

The iterative algorithm for decoding binary BCH codes presented by Berlekamp and, in an alternative form, by Massey is modified to eliminate inversion. Because inversion in a finite field is time consuming and requires relatively complex circuitry, this new algorithm should he useful in practical applications of multiple-error-correcting binary BCH codes. View full abstract»

• ### On upper bounds for unrestricted binary-error-correcting codes

Publication Year: 1971, Page(s):466 - 478
Cited by:  Papers (25)
| | PDF (1523 KB)

In this paper improved upper bounds are obtained for<tex>A(n,d)</tex>, the maximum number of binary code vectors in a code of block length<tex>n</tex>and minimum distance<tex>d</tex>. Known bounds are presented in a unified way and then refined, giving improvement over best previously published results in almost all cases. Finally, tabulations of the improved re... View full abstract»

• ### Construction of minimum-redundance codes with an optimum synchronizing property

Publication Year: 1971, Page(s):478 - 487
Cited by:  Papers (26)  |  Patents (4)
| | PDF (1547 KB)

A simple method has been found for constructing a minimum-redundancy code having the shortest possible synchronizing sequence. For most variable-length codes the propagation of an error is halted by the next appearance of certain naturally occurring synchronizing sequences. Although the time between error and resynchronization has no upper bound, the length<tex>r</tex>of the shortest r... View full abstract»

• ### On decoding of maximum-distance separable linear codes

Publication Year: 1971, Page(s):487 - 491
Cited by:  Papers (4)
| | PDF (774 KB)

In this paper, some properties of maximum-distance separable linear codes are presented. Based on these properties, a decoding algorithm for correcting random errors is established. A simpler decoding algorithm for correcting burst errors is also given. Applying these decoding algorithms to known classes of maximum-distance separable linear codes, the amount of hardware required for implementation... View full abstract»

• ### Note on approximating discrete probability distributions (Corresp.)

Publication Year: 1971, Page(s):491 - 493
Cited by:  Papers (1)
| PDF (461 KB)
• ### Alternative interpretation of maximum entropy spectral analysis (Corresp.)

Publication Year: 1971, Page(s):493 - 494
Cited by:  Papers (187)
| | PDF (287 KB)

Maximum entropy spectral analysis is a method for the estimation of power spectra with a higher resolution than can be obtained with conventional techniques. This is achieved by extrapolation of the autocorrelation function in such a way that the entropy of the corresponding probability density function is maximized in each step of the extrapolation. This correspondence also gives a simple interpr... View full abstract»

• ### New algorithm for stochastic approximation (Corresp.)

Publication Year: 1971, Page(s):494 - 495
Cited by:  Papers (2)
| | PDF (246 KB)

A general stochastic approximation algorithm is given along with assumptions and conditions necessary to show that it converges. Convergence is proven in the mean-square sense. The rate of convergence is shown to be better than two algorithms proposed previously. View full abstract»

• ### Relations among sequency, axis symmetry, and period of Walsh functions (Corresp.)

Publication Year: 1971, Page(s):495 - 497
Cited by:  Papers (5)
| | PDF (417 KB)

A parameter is defined that distinguishes the members of the set<tex>\{WAL(s,m)\}</tex>of Walsh functions. There is a one-to-one correspondence between sequency and axis symmetry of each Walsh function. Axis symmetry is derived from the sequency number. A procedure is introduced for obtaining the period of a Walsh function from its sequency number. View full abstract»

• ### Computing approximations for the generalized Q function and its complement (Corresp.)

Publication Year: 1971, Page(s):497 - 498
Cited by:  Papers (13)
| | PDF (300 KB)

The Chernoff bound is used to derive useful approximations for the generalized<tex>Q</tex>function and its complement. View full abstract»

• ### Discriminatory dimensionality reduction (Corresp.)

Publication Year: 1971, Page(s):498 - 499
Cited by:  Papers (1)
| | PDF (332 KB)

Truncated optimal entropy-minimizing expansions can serve to characterize classes of multivariate data. A method is presented here by which the level of truncation and the corresponding dimensionalities of the class subspaces can be chosen to ensure adequate discrimination. The subspaces are chosen to maximize the average margin of correct classification of the paradigms of one class subject to co... View full abstract»

• ### Structure and Parameter Adaptive Pattern Recognition With Supervised Learning: A New Formulation

Publication Year: 1971, Page(s):499 - 500
Cited by:  Papers (4)
| | PDF (308 KB)

A new formulation of the problem of structure and parameter adaptive pattern recognition with supervised learning yielding significant computational advantages is presented. View full abstract»

• ### Simple data compression by redundancy replacement (Corresp.)

Publication Year: 1971, Page(s):500 - 503
Cited by:  Patents (1)
| | PDF (591 KB)

A redundancy replacement system is described. Whenever<tex>m</tex>bits of an<tex>n</tex>-bit word are identical with corresponding bits in the preceding word, these bits are replaced by<tex>m</tex>bits from a second source. An extra bit is added to each word to signal the substitution. If words with<tex>m</tex>redundant bits occur with probability<... View full abstract»

## Aims & Scope

IEEE Transactions on Information Theory publishes papers concerned with the transmission, processing, and utilization of information.

Full Aims & Scope

## Meet Our Editors

Editor-in-Chief
Alexander Barg

Department of Electrical and Computer Engineering and the Institute for Systems Research, University of Maryland

email: abarg-ittrans@ece.umd.edu