Millimeter wave gunn diode oscillators

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2007
Lüy, Ülkü
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This thesis presents the design and implementation of a millimeter-wave Gunn diode oscillator operating at 35 GHz (Ka (R) 26.5-40 GHz Band). The aim of the study is to produce a high frequency, high power signal from a negative resistance device situated in a waveguide cavity by applying a direct current bias. First the physics of Gunn diodes is studied and the requirements that Gunn diode operates within the negative differential resistance region is obtained. Then the best design configuration is selected. The design of the oscillator includes the design of the waveguide housing, diode mounting and the bias insertion network. Some simulation tools are used to predict, approximately, the behaviour of the oscillator and the bias coupling circuit. For tuning purposes, a sliding backshort and a triplescrew- tuner system is used. For different bias values and different positions of the tuning elements oscillations are observed. A much more stable and higher magnitude oscillations were obtained with the inclusion of “resonant disc” placed on top of the diode. 15 dBm power was measured at a frequency of 28 GHz. Laboratory measurements have been carried out to determine the oscillator frequency, power output and stability for different bias conditions.
Electronics.
http://etd.lib.metu.edu.tr/upload/2/12608759/index.pdf
https://hdl.handle.net/11511/17135
Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats
Ü. Lüy, “Millimeter wave gunn diode oscillators,” M.S. - Master of Science, Middle East Technical University, 2007.
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