Whitepapers

Reconfigurable And Cost-Effective FET Mixer

This paper describes a reconfigurable resistive passive FET mixer co-designed with a reconfigurable VCO (voltage controlled oscillator) that acts as a LO (local oscillator), can operate with low noise figure, and high dynamic range without the need of external BALUN (balance-to-unbalance) network. The typical measured input intercept points (IIP3) and conversion loss is 38dBm and 8.5dB with the LO power typically 15dBm for the frequency bands (RF: 700-2300MHz, LO: 650-2100MHz, IF: 50-200MHz).
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The Class M™ Linearization System and Its Application

An excellent technique for on channel linearization enhancement is feedback of the incident signal from output to input, provided sufficient loop gain and phase margin exist within the system. Class M™ is an example of a pulse shaping system for complex envelope modulation control that employs real time feedback at radio frequency to maintain high levels of distortion correction and loop stability.
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Wireless and Stimulus: A Perfect Match

When it comes to securing broadband stimulus funds, network providers are currently faced with some fairly uncertain circumstances. Challenged with navigating through the uncertain fund allocation process, operators continue to struggle with determining how to write a convincing and winning application and choosing the right solution, technology and vendor to best suit their specific needs.
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Generating X-parameters from Circuit-level Designs

X-parameters represent a new category of nonlinear network parameters for high-frequency design and are used for characterizing the amplitudes and relative phase of harmonics generated by the nonlinear behavior of components. Developed and introduced by Agilent Technologies, X-parameters are applicable to both large-signal and small-signal conditions, and for linear and nonlinear components. They correctly characterize impedance mismatches and frequency mixing behavior to allow accurate simulation of cascaded nonlinear X-parameter blocks (e.g., amplifiers and mixers), in wireless design. X-parameters play a key role in the development of active devices like the power amplifier (PA) and mixers—critical components in today’s wireless designs.
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Understanding Long-Term Evolution Fundamentals and Measurement Challenges

The Universal Mobile Telecommunication System (UMTS), the successor to GSM, is steadily increasing its penetration of the world’s wireless communications markets, and is likely over time to become the primary standard used by not just the current 85% wireless carriers, but by virtually all of them. Its most promising emerging enhancement, Long-Term Evolution (LTE), has moved further along in the standards-setting process and on to the path of initial deployment.
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A Comparison Between Thin Film and Thick Film Capacitors

Capacitor technology is constantly evolving and advancing to meet design engineers’ requirements as they develop the latest electronic designs. Whether a new design or redesign is driven by size or performance requirements (or both), design engineers are in need of advanced components that enable them to produce smaller, faster, higher performance designs.
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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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