Definition

The European Space Agency (ESA) has programmes underway to place Satellites carrying optical terminals in GEO orbit within the next decade. The first is the ARTEMIS technology demonstration satellite which carries both microwave and SILEX (Semiconductor Laser Intro satellite Link Experiment) optical interorbit communications terminal. SILEX employs direct detection and GaAIAs diode laser technology; the optical antenna is a 25cm diameter reflecting telescope.

The SILEX GEO terminal is capable of receiving data modulated on to ....etc

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Abstract.
We consider updates to an n-dimensional frequency vector of a data stream, that is, the vector f is updated coordinate-wise by means of insertions or deletions in any arbitrary order. A fundamental problem in this model is to recall the vector approximately, that is to return an estimate ^ f of f such that j ^ fi ....etc

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Abstract
The need of low-loss substrate materials with stable dielectric performances over a wide frequency range is a strong
requirement when working at millimeter frequencies, where standard dielectric substrates exhibit prohibitive losses. In
this contribution, the authors focus their attention on a polymer material, the benzocyclobutene (BCB), having a low
dielectric constant equal to 2.65, and a low loss tangent, equal to 0.0008 at 1 GHz, with a stable dielectric behavior
over a broad frequency range, up to THz. The use of BCB ....etc

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ROBUST DWT-SVD DOMAIN IMAGE WATERMARKING: EMBEDDING DATA IN ALL FREQUENCIES
Watermarking (data hiding) is the process of embedding data into a multimedia element such as image, audio or video. This embedded data can later be extracted from, or detected in, the multimedia for security purposes. A watermarking algorithm consists of the watermark structure, an embedding algorithm, and an extraction, or detection, algorithm. Watermarks can be embedded in the pixel domain or a transform domain. In multimedia applications, embedded watermarks shou ....etc

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The beginning of new millenium sees an important milestone in military aviation communication with the introduction of the first Super-High-Frequency (SHF) airborne satellite communication (Satcom) terminals, which are due to enter service on Nimrod maritime reconnaissance aircraft (MRA4). Satcom terminals using the Ultra-High-Frequency (UHF) band have been fitted to larger aircrafts for a number of years. Although relatively simple to install and comparatively inexpensive, UHF satcoms(240-270 & 290-320 MHz bands) suffers from very limited capa ....etc

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Abstract
LEO is Low Earth Orbit satellite.It circulates on a lower orbit in a shorter period . Additionally LEO systems try to ensure a high elevation for every spot of the earth to provide a highquality communication page link . The networks will play an important role in the evolving information infrastructure . It provides communication with shorter endto- end delays and e_ciency frequency usages . Some problems need to be solved before LEO satellite system can be successfully deployed . One of these problems is handover management . Even ....etc

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HIGH THROUGHPUT AND LOW POWER REED SOLOMEN DECODER FOR ULTRA WIDE BAND FREQUENCIES

Abstract:- Reed Solomon (RS) codes have been widely used in a variety of communication systems such as space communication link, digital subscriber loops and wireless systems, as well as in networking Communications and magnetic and data storage systems. Continual demand for ever-higher data rates and storage capacity makes it necessary to devise very high-speed implementations of RS Decoders. Newer and faster implementations of the decoder are being developed ....etc

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CHAPTER 1
INTRODUCTION

Communication links between space crafts is an important element of space infrastructure, particularly where such links allow a major reduction in the number of earth stations needed to service the system. An example of an inter orbit page link for relaying data from LEO space craft to ground is shown in the figure below



Interorbit page link for relating data from LEO spacecraft to ground

Fig. 1
Inter orbit page link for relaying data from LEO space craft to ground.


The above figure represents a ....etc

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ABSTRACT
This paper outlines some of the techniques being developed to provide affordable, reliable satellite communications suitable for a wide range of military aircraft, from agile platforms such as jets and helicopters to surveillance, tanker and transport aircraft. It also gives an overview of airborne SHF (Super High Frequency) and also EHF (Extremely High Frequency) satcom techniques. Although presently used UHF (Ultra High Frequency) satellite communication are relatively simple to install and comparatively inexpensive, suffer from ....etc

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Definition

The European Space Agency (ESA) has programmes underway to place Satellites carrying optical terminals in GEO orbit within the next decade. The first is the ARTEMIS technology demonstration satellite which carries both microwave and SILEX (Semiconductor Laser Intro satellite Link Experiment) optical interorbit communications terminal. SILEX employs direct detection and GaAIAs diode laser technology; the optical antenna is a 25cm diameter reflecting telescope.

The SILEX GEO terminal is capable of receiving data modulated on to ....etc

[:=Read Full Message Here=:]