Design and fabrication of a detector logarithmic video amplifier

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2011
Dinç, Mustafa Barış
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In this thesis a single stage detector logarithmic video amplifier is designed with a dynamic range of 40dB in 2-6GHz frequency band. Since the detector logarithmic video amplifier (DLVA) is used to convert the power of the RF signals to video voltages in logarithmic scale, it can be regarded as a logarithmic converter instead of logarithmic amplifier. The design is composed of two main parts: The Schottky diode detector rectifies the incoming RF signal and produces a video voltage and the logarithmic amplifier transforms the scale of the video voltage from linear scale to logarithmic scale in order to observe the RF signals with a wide amplitude range. The approximation of the logarithmic function is obtained by the summation of the output currents of the differential amplifiers operating as logarithmic stages. Offset voltage of the DLVA is minimized in order to obtain maximum sensitivity; this makes the detection of RF signals with low power possible. The study is composed of mainly three parts: First, brief information about logarithmic amplification techniques is given and the circuit architecture is developed for logarithmic amplification and video detection, second these circuits are simulated and finally the design is implemented and tested.
Intelligent transportation systems.
http://etd.lib.metu.edu.tr/upload/12613617/index.pdf
https://hdl.handle.net/11511/21057
Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats
M. B. Dinç, “Design and fabrication of a detector logarithmic video amplifier,” M.S. - Master of Science, Middle East Technical University, 2011.
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