U.S. Philips Corporation

U.S. Phillips Corporation

Hendrik D Hollmann

Johannes O Voorman

Johannes W Bergmans

Robert J Sluijter

Constant P Baggen

Cornelis M Huizer

Hendrik Tjalling Dijkstra

Constantijn D Holzscherer

A digital information signal is channel encoded into a channel signal. Data sequences in the channel encoded information signal that give rise to an analog signal, upon reproduction or reception, with a single frequency component at f.sub.b M, are limited in length. M being an integer constant larger than 2 and f.sub.b being the bit frequency in the channel encoded information signal.

Transmission, recording and reproduction of a digital information signal

A circuit arrangement calculates pseudo-random permutations of a set of numbers. Including compositions of some basic pseudo-random permutations and the inverse permutations of permutations that are calculated. The basic pseudo-random permutations, their compositions and inverses are all calculated by the same generator whose operation is commanded to calculate the appropriate permutation by specifying a set of integer coefficients f.sub.i. The generator calculates the permutations .sigma.(n) of the numbers n=0 . . . m-1 corresponding to ##EQU1## where .alpha. is an integer number which is divisible by all prime factors of m and by four if m is divisible by four, with a potency s(.alpha.) of two or higher. When the same a is used for all permutations it is assured that all compositions and inverses of the generated permutations can be calculated in the same way, by the same generator. By storing a batch of items in a storage medium in a first order and retrieving the items from the storage medium in a second order, the first and second order corresponding to different permutations which are both of this type, it is made possible to permute the batch pseudo randomly and start storing the batch of items in the storage medium before a previous batch has been fully retrieved from it.

Circuit arrangement comprising a permutation unit and method of

In a presentation system a transmitter station transmits messages that provide information on demand. Such message is divided into parts. An earlier part of the message is presented more often than at least one later part of the messages. In particular, the presentation pattern is such that upon accessing the message's firts parts all other parts can be contiguously accessed according to a standard presentation velocity as from a time instant that is within a prespecified distance in time from the start of accessing said first part. In particular, the distance may be zero.

Presentation system for messages that provide information on demand and

A coupling network for a data processor is described, including, one or more cross bar switches having inputs and outputs and one or more arrays of silos. A series connection is formed in which these components are alternately arranged in a succession having at least three elements. A retrocoupling network is used for coupling outputs of a data processor to its inputs, and it also provides external communication. The configuration offers ample freedom of mapping, notably in cyclostatic processors.

Coupling network for a data processor, including a series connection of

There is described the calculation of a multiplicatively inverted element of an input vector specified in a finite major Galois field. From the set of vector coefficients there is formed a first set of linear forms and a further set of matrix-organized linear forms. The elements of the first set of linear forms are pairwise combined to quadratic forms that represent a set of coefficients of a vector defined in a subfield in the major field. This latter vector is then converted to its multiplicative inverse, after which the inverted subfield-vector has its coefficients multiplied by elements of the further set to generate the multiplicative inverse in the major field. By scrupulously combining the generation of various intermediate terms a further reduction of the necessary hardware and/or processing time is attained.

Growing community of inventors

Eindhoven, Netherlands

Hendrik D Hollmann