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Your search keyword '"Ultra high frequency"' showing total 14 results
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14 results on '"Ultra high frequency"'

1. An approach to low noise amplifier optimization in Advanced Design System CAD

Author

Galina Nikolaevna Nazarova, Vadim Vladimirovich Elesin, and Denis Ivanovich Sotskov

Subjects
low noise amplifier, ultra high frequency, CAD, Information technology, T58.5-58.64, Information theory, Q350-390
Abstract

An approach to silicon low noise amplifier (LNA) optimization, intended for use in the CAD Advanced Design System, has been presented. The approach is based on a technique using the contour plots of LNA parameters such as operating current, transistor width, impedancematching circuit elements, minimizing the noise figure of the LNA, and providing sufficient gain and VSWR. The ability to use the models of real silicon passive and active elements, and consider the impact of the bond wires inductance is an advantage of the proposed approach. LNA optimization procedure consists of three steps. The first step is a schematic selection of the input stage LNA, specifying the operating current and providing input impedance matching. At the second step an optimization procedure with the built-in CAD optimization tools is used to calculate the contour plots of LNA parameters at one frequency point for all implementable set of values of the operating current and the input stage transistor width. Finally, optimal values of selected LNA schematic elements are defined using the calculated contour plots. The presented approach has been tested at 1,4 GHz LNA design, intended for use in a global positioning system receiver, to be implemented in a 0,35 um SOI CMOS process. The LNA provides a forward gain of 19 dB with a noise figure of only 1.6 dB, VSWR of 1,45 while drawing 60 mW from a 3,3 V supply.

Published
2016

2. EXPERIMENTAL RESULTS OF SOFTWARE ALGORITHMIC SYNCHRONIZATION OF DISTRIBUTED RADIO SYSTEM WITH MOBILE CARRIERS

Author

I. V. Kryuchkov, M. I. Noniashvili, A. I. Skachkova, and A. A. Filatov

Subjects
Broadcast engineering, TK7800-8360, Computer science, 010401 analytical chemistry, Synchronizing, 020206 networking & telecommunications, 02 engineering and technology, Antenna diversity, Phase synchronization, 01 natural sciences, Signal, Synchronization, crystal oscillator, 0104 chemical sciences, Ultra high frequency, Transmission (telecommunications), software algorithmic synchronization mode, spatial coherence, 0202 electrical engineering, electronic engineering, information engineering, Electronic engineering, distributed radio system, Electronics
Abstract

Introduction. One of the classes of modern radio engineering systems are systems with spatial diversity of transmitting, receiving or transceiving elements. In such systems, an increase of the information content is achieved by signal coprocessing ensuring synchronization in time and phase of the carrier oscillation. Currently, the researchers do not pay enough attention to the requirements for the accuracy of synchronization of distributed systems of different applications, as well as simple and affordable ways to synchronize them.Objective. The paper main objective is the search for technical solutions for clock and phase synchronization without atomic frequency standards and external sources of coordinate-time information.Methods and materials. The paper considers a distributed radio engineering system with non-rigid structure. Each element of the system has reference signal from its own crystal oscillator. The oscillators are not physically aligned. The phases of their oscillations are periodically compared by the method of two-way transmission of synchronizing signals (from one element to another and vice versa). The synchronization technique (software algorithmic approach) is reduced to the coprocessing signal correction according to estimated frequency (phase) drifts. The testing of the proposed technical solution is presented on a hardware model consisting of ten receiving and transmitting modules.Results. The experiment showed that RMS of synchronization errors does not exceeded 12 degrees by phase (for VHF), or 0.2 ns by time. These results are acquired for spatial diversity up to several hundred meters, mutual speed of the modules up to several meters per second and may be extended for higher frequencies (in particular, UHF).Conclusion. The paper proposes a method of multilateral propagation to synchronize distributed radioengineering systems. Combined with software algorithmic technique this method enables to obtain synchronization accuracy in real-time sufficient for coherent diversity technique.

Published
2019

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