Whitepapers

Satellite DVB-RCS Standards for Fixed and Mobile Commercial and Military Applications

The first generation of satellite standard of DVB-S known as Digital Video Broadcasting-Return Channel via Satellite (DVB-RCS) about ten years ago quickly became around the globe one of the key solutions in almost every new satellite communication project for broadcast, broadband and multimedia interactive applications including high-speed Internet. The second generation of DVB-S2 CCM (Constant Coding Modulation) standard was presented a few years ago as a new more cost effective, efficient, reliable, secure and functional solution. The DVB-S2 CCM can be upgraded and cost less than the third generation of DVB-S2 ACM (Adaptive Coded Modulation) platform, forward and reverse compatible. In this article will be introduced the latest DVB-S2 Space and Ground segments, respectively, for interactive transmission of Voice, Data and Video (VDV) over IP (VDVoIP). The Ground Segment will be represented by HUB as GES (Ground Earth Station) and VSAT equipment known Satellite Interactive Terminal (SIT) or Remotes, compliant to all DVB-RCS standards for civilian and military solutions.
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Airborne Satellite Antenna Mount and Tracking Systems

The communication Mobile Satellite Antenna (MSA) for transport applications are relatively large and heavy, especially the airborne High Gain Antenna (HGA) system for Inmarsat-H and High Speed Data (HSD) Aircraft Earth Stations (AES). Thus, over the past decade the steering airborne antenna system, which comprises the mechanical assembly, the control electronic system, the microwave electronic package and the antenna assembly (arrays and steering elements), has been reduced considerably in both physical size and weight. These reductions brought about by greater Effective Isotropic Radiated Power (EIRP) from satellite transponders coupled with GaAs-FET technology at the front end the receiver leading to higher G/N RF amplifiers, have made initially the fitting of shipborne antennas on tracks, locomotives and airplanes a reality. A little later airborne and vehicle borne MSA were developed on the basis of these shipborne antennas. The MSA systems are always required to be pointed towards the satellite in spite of mobile motions. Namely, the mount system is one of the main requirements in designing the MSA systems from the technical and rational viewpoints. The several types of mount system are used: such as mechanical, electrical and other, especially those concerned with shipborne MSA. Whereas, in the case of airborne and vehicleborne MSA, electrical pointing systems are preferable.
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Extending 2.4 GHz ZigBee Short Range Radio Performance

The SKY65336 and SKY65337 ZigBee front-end modules (FEMs) can greatly enhance the performance of a ZigBee radio solution when integrated with any ZigBee low power reference design. Both devices can transmit up to 100 times more power than a typical 0 dBm low power ZigBee radio transmitter and can reduce the level of unwanted spurious emissions to be compliant with the main regulatory standards without the use of external components such as filters. Ember’s EM250 with Skyworks’ FEM reference design [1] shows a good example of the complete subsystem.
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Spacecraft Payload for MSC Networks

A Mobile Satellite Communications (MSC) system is radio-relay station temporarily located at determined position in space (approximately between 20 and 36,000 km) to receive RF signals from different Mobile Earth Stations (MES), amplify the signals and transmit them back to Land Earth Stations (LES), which are connected to the ground telecommunication infrastructure. To provide those all functions in order satellite has to be equipped with adequate subsystems integrated by payload and bus. The payload is usually located inside of satellite body, which contains the transponder or transceiver system (satellite receivers and transmitters). The transponder is also connected to the receiving and transmitting antenna system, which are mounted outside on the satellite body. Therefore, each satellite must be stabilized in its orbital slot, which has to counteract the forces acting on the satellite motion and to keep the antennas of a satellite constantly pointing to a specific footprint of the Earth.
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How to Specify RF and Microwave Filters

As one of the fundamental signal processing components in RF and microwave circuits, the filter plays a critical role in determining any system’s ultimate performance. Since the electromagnetic spectrum has become more and more densely populated, filter performance has taken on greater significance than ever because interference rejection is of paramount importance.
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Advancements in Process Residue Adhesion Decrease Chip Defects and Increase Yields

With marching orders to improve process uptime, drive down manufacturing costs and improve or maintain yield, while decreasing process-related defects, the semiconductor industry is turning to new materials that help meet their needs. The emerging solar technology industry is also using the materials to drive down their costs and increase their competitiveness in the marketplace
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Analysis of Quick Lock N Type Connectors

The N series of coaxial connector is the most widely used series for low to medium power applications in the DC to 11 GHz frequency range. The N connector is particularly well suited for applications in harsh environments or those where there is a high number of mating cycles. A relatively recent improvement has been the introduction of the Precision N connector, which operates up to 18 GHz. A major inconvenience of the traditional N connector is the threaded coupling mechanism. This has led to the invention of the Quick Lock N (QL-N) type connector, which showcases a quick disconnect feature.
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SMA Connector Frequency Extension

At the SMA connector’s inception, the operating frequency didn’t exceed 12 GHz. As the design matured, the maximum operating frequency was pushed up to 18 GHz and eventually higher. As higher operating frequencies have become common over the past several decades, other interfaces, most of which are considered precision interfaces designed for laboratory use, have been introduced to handle signal transmission at frequencies far exceeding 18 GHz. However, the SMA connector design can be optimized to extend the maximum operating frequency of the interface to offer a reliable and cost-effective solution to the higher frequency requirements of modern systems.
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Beyond Conformance Testing in 3GPP LTE

This paper describes how LTE products, systems and applications are tested in a realistic wireless environment – not in the field but in a laboratory. The benefits of beyond conformance testing compared to standard conformance testing are explained. LTE terminal and base station manufacturers as well as operators are recommended to go beyond basic testing and carry out performance measurements already in the early phases of LTE product development. The White Paper also discusses the different testing methods and introduces key radio channel models which can be used in the testing process.
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