• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.11
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• pp.1170-1175
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• 2003

In this paper, the output power improvement of Push-Push FET DRO by adding the identical DR at the drain port as one used in the gate port, has been theoretically investigated. The investigation shows that the DR located between two microstrip lines locks the phase difference of two FET's outputs at 180 degree and improves the output power of Push-Push FET DRO. Since this effect can be used for correcting the impedance difference between two FETs output circuits and the electrical length error of the power combiner at the output circuit of Push-Push DRO, which may occur when fabricate the oscillator, the oscillator with an additional DR can be useful structure for fabricating oscillator.

• Journal of Advanced Navigation Technology
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• v.7 no.1
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• pp.1-5
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• 2003

In this paper, the output power level and phase noise property of nine conventional push-push FET DROs (Dielectric Resonator Oscillator) have been experimentally investigated by adding one more identical DR at the drain port. The nine oscillators designed to generate 20 GHz from 10 GHz fundamental frequency, have been tested for each of three different power combiners at the output port. It has been observed that the output power level of the push-push FET DROs can be improved by placing the DR while maintaining their phase noise characteristics were approximately the same as before adding the DR.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.385-388
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• 2000

In this paper, the Ka-band Dielectric resonator oscillator has been designed and fabricated. The resonator network was simulated using HFSS program. The design method of an oscillator is the small-signal S-parameter design. The Push-push DRO employs a hetero junction FET (NE32484A). The fabricated Push-push DRO shows such characteristics as the phase noise -106 ㏈c/Hz at the 100 ㎑ frequency offset. the output power and fundamental frequency surpression were -6 ㏈m and -29 ㏈c, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.7
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• pp.613-624
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• 2002

Electrical characteristics of two types of 20 GHz Push-Push GaAs MESFET dielectric resonator oscillators having Wilkinson and T-junction power combiners for the output stage have been investigated and compared. So we have explained that the output power and phase noise properties of the Push-push FET DRO are depending on return loss and isolation characteristics of power combiner at the fundamental and the second harmonic frequencies. A Push-push oscillator for suppressing the fundamental frequency of 10 GHz and enhancing the second harmonic of 20 GHz has been designed and fabricated in microstrip configuration on 20 mil thick RT-Duroid($\varepsilon$$_{r}$ = 2.52) Teflon substrate. Return loss and isolation characteristics of T-junction and Wilkinson have been measured at the fundamental frequency of 10.2 GHz and the second harmonic frequency of 20.5 GHz. At the fundamental frequency, -12 dB return loss and -3.7 dB isolation have been measured for the T-junction power combiner, and -14 dB return loss and -11 dB isolation fur the Wilkinson power combiner. At the second harmonic frequency, -10 dB return loss and -7.5 dB isolation have been obtained for the T-junction power combiner, and -23 dB return loss and -22 dB isolation for the Wilkinson power combiner. As a result, we have confirmed that the oscillator based on the Wilkinson power combiner with better retrun loss and isolation characteristics produces more output power and better phase noise characteristics..