Document transfer by a digital satellite link

In this paper the general user and system requirements are specified for an electronic document delivery (EDO) system and a protocol is given for a high-resolution EDD system by satellite. The proposed system is compatible with the APOLLO system concept for bulk data transfer via satellite, developed by the European Space Agency (ESA)....

System design study for an electronic document delivery system

The objectives of this study are to define the technical facilities which are required for electronic document delivery over a satellite link. In this report, the user requirements and system requirements are analysed for the complete chain of Electronic Document Delivery (EDD) facilities, consisting of archiving, transmission and reproduction...

Error correcting coding for satellite communications

This report describes the most relevant block- and convolutional codes to be used in satellite communication systems. Design trade-offs are given for the choice of coding techniques in SCPC, TDMA and SS-TDMA communication system,

Channel coding with the (255,255-2T) Reed-Solomon codes over CF(256)

The class of (255, 255-2T) Reed-Solomon codes over CF(256) is studied in detail. In particular the encoding and decoding algorithms are elaborated. Main computational elements are the discrete Fourier transform for syndrome and error locator computation, Euclid's algorithm for solving the key equation and Horner's scheme for determining the...

A method for measuring take-off sjid landing performance of aircraft, using an inertial sensing system

The STALINS method for measuring take-off and landing trajectories is briefly described and results of flight tests made in 1978-80 are discussed. The method now meets the requirements to which it was designed, and a few improvements in the hardware and software are being finalized. The method is expected to be ready for operational use in the...

A method for applying linear optimal control theory to the design of a regulator for a flexible- aircraft

This report deals with determining a hypothetic control system which provides improved rigid body and structural mode damping of a flexible aircraft in order to improve the riding qualities and to minimize the wing bending moment during flights in turbulence. The equations of motion used in the computations are related to a high' performance...

On the approximate solution of the transonic small perturbation equation with a Galerkin/least-squares method and bicubic hermite functions

The two-dimensional transonic small-perturbation equation is solved by a higher-order finite element method using a combination of a Galerkin orthogonalization procedure and a least-squares method. It is shown that this higher-order method requires a non-trivial formulation of the discrete boundary conditions. The Galerkin orthogonalization...

Evaluation of a method to extract performance data from dynamic maneuvers for a jet transport aircraft

A very accurate measurement system and a data reduction method have been developed to extract performance data from a single dynamic maneuver, in order to reduce the large amoimt of flight hours required for the determination of these data by means of measurements in steady flight. In order to evaluate the applicability of this method to a modem...

Conclusies van enkele oriënterende studies voor een rekenmethode voor drie-dimensionele transsone potentiaal stromingen om romp-vleugel configuraties

Image data security in the concept of the agricultural real time imaging satellite system (ARTISS): EUROCON '77 paper

The user's requirement to have quick and exclusive access to satellite imagery of the own territory leads to decentralized reception and processing of the image data. The exclusiveness of imagery requires additional security measures for the satellite-user station link. Two methods for protection of the transmission of image data are proposed: ...

Image data security in the concept of the agricultural real time imaging satellite system (artiss)

The study on image data security is directed to the requirement for exclusive access to satellite imagery in the concept of the Agricultiiral Real Time Imaging Satellite System (ARTISS). The security assessment indicates that user survey requests are handled confidentially and it shows the access vulnerability of the transmission of image data...

Conditional Recurring Sequences

The theory of linear recurring sequences is generalized to the case of a limite set of generating functions. Sequences generated by such a set are called conditional recurring sequences and their properties are are investigated. Several examples are given.