| 1. |
- Angelov, Iltcho, 1943, et al.
(författare)
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A balanced millimeter wave doubler based on pseudomorphic HEMTs
- 1992
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Ingår i: 1992 IEEE MTT-S International Microwave Symposium Digest. - 0149-645X. ; 1, s. 353-356
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Konferensbidrag (refereegranskat)abstract
- A balanced HEMT (high electron mobility transistor) doubler for operation at millimeter waves has been analyzed, fabricated, and characterized. Particular attention has been paid to the influence of the output circuit on the performance of the doubler. The doubler was analyzed with a harmonic balance method and an output power of 4 dBm at 42 GHz was obtained experimentally. The conversion gain is approximately -1 dB at 40 GHz at an input power of 5 dBm. Bias and frequency response were very close to the predicted ones.
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| 2. |
- Angelov, Iltcho, 1943, et al.
(författare)
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A new empirical nonlinear model for HEMT-devices
- 1992
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Ingår i: 1992 IEEE MTT-S International Microwave Symposium Digest. - 0149-645X. - 0780306112 ; 3, s. 1583-1586
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Konferensbidrag (refereegranskat)abstract
- A novel signal model for HEMTs (high-electron-mobility transistors) capable of modeling the current-voltage characteristic and its derivatives, including the characteristic transconductance peak and gate-source and gate-drain capacitances, is described. Model parameter extraction is straightforward and is performed for a submicron gate-length ∂-doped pseudomorphic HEMT. The model has been used to predict the DC- and S-parameters of the devices and different nonlinear circuits such as mixers and multipliers with very high accuracy.
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| 3. |
- Angelov, Iltcho, 1943, et al.
(författare)
-
F-band resistive mixer based on heterostructure field effect transistor technology
- 1993
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Ingår i: Proceedings of the 1993 IEEE MTT-S International Symposium on Circuits and Systems. - 0149-645X. - 0780312090 ; 2, s. 787-790
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Konferensbidrag (refereegranskat)abstract
- A fundamentally pumped millimeter wave resistive mixer based on an HFET technology working at F-band (90-140 GHz) is described for the first time. Nonlinear simulations have been performed for this mixer based on an specially designed double δ-doped pseudomorphic HFET device developed for this application. A minimum conversion loss between 12 to 13 dB was measured with the RF fixed at different frequencies between 108 to 114 GHz at an RF power of -13 dBm. Both theoretical and experimental results are presented in this paper.
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| 4. |
- Rorsman, Niklas, 1964, et al.
(författare)
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Characterization of InAlAs/InGaAs HFETs with high indium content in the channel grown on GaAs substrate
- 1993
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Ingår i: 23rd European Solid State Device Research Conference, ESSDERC 1993. - 1930-8876. - 9782863321355 ; , s. 765-768
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Konferensbidrag (refereegranskat)abstract
- InAlAs/InGaAs HFETs having very high indium content (80 and 100%) in the channel have been fabricated on GaAs and electrically characterized. The extrinsic transconductance were 310 mS/mm (560 mS/mm at 77 K), and the saturation current were 700 mA/mm (600 mA/mm at 77 K) for an InAs channel. The value of fT and fmaxfor this device were measured to be 80 GHz and 50 GHz, respectively. The In0.8Ga 0.2As channel material had extrinsic transconductance of 320 mS/mm (470 mS/mm at 77 K), and the saturation current were 520 mA/mm (440 mA/mm at 77K). The value of fT and fmaxfor this device were measured to be 80 GHz and 50 GHz, respectively
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| 5. |
- Strupinski, W., et al.
(författare)
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New method for determination of the peak-velocity in epitaxial semiconductor structures by dc measurements on microbridges
- 1991
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 59:24, s. 3151-3153
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Tidskriftsartikel (refereegranskat)abstract
- A simple current-voltage measurement technique using microbridge patterns is described as a fast method for the determination of the effective peak electron velocity in III-V semiconducting materials. The method is tested for GaAs samples. Microbridge patterns with different geometries were investigated and the influence of ''self-heating'' by power dissipation was examined. Some other potential sources of errors deteriorating the accuracy of measurements were determined.
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| 6. |
- Zirath, Herbert, 1955, et al.
(författare)
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A millimeterwave subharmonically pumped resistive mixer based on a heterostructure field effect transistor technology
- 1992
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Ingår i: 1992 IEEE MTT-S International Microwave Symposium Digest. - 0149-645X. - 0780306112 ; 2, s. 599-602
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Konferensbidrag (refereegranskat)abstract
- A subharmonically pumped resistive mixer (SPRM) working at millimeter waves based on a heterostructure FET (HFET) technology is described. Nonlinear simulations of the mixer were performed and a special dual HFET chip was developed and fabricated for the demonstration of this mixer. Mixer circuits were fabricated and operational characteristics at 40-45 GHz were investigated.
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| 7. |
- Zirath, Herbert, 1955, et al.
(författare)
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Characteristics of a millimeter wave drain mixer
- 1992
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Ingår i: Proceedings of the 22nd European Microwave Conference. - 0946821879 ; 2:22, s. 987-992
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Konferensbidrag (refereegranskat)abstract
- Different drain mixer configurations, based on Heterostructure Field Effect Transistors (HFET), working at millimeter waves were studied. The mixer has a conversion gain of 6-7 dB at 40 GHz with 5GHz RF-bandwidth. This is the highest reported gain for an HFET-mixer working in this frequency band.
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| 8. |
- Zirath, Herbert, 1955, et al.
(författare)
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HFET millimeterwave resistive mixer
- 1992
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Ingår i: Proceedings of the 22nd European Microwave Conference. - 0946821828 ; 1:22, s. 614-619
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Konferensbidrag (refereegranskat)abstract
- A millimeterwave resistive mixer based on a heterostructure field effect transistor (HFET) is described. A minimum conversion loss of 8 dB, including losses in the connectors, filters, substrates etc, is obtained in the frequency range 40-45 GHz. This is the highest frequency of operation reported for this type of mixer.
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| 9. |
- Zirath, Herbert, 1955, et al.
(författare)
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Resistive HEMT-mixer with very low LO-power requirements and low intermodulation
- 1991
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Ingår i: European Microwave Conference. - 094682147X ; 2, s. 1469-1474
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Konferensbidrag (refereegranskat)abstract
- The channel resistance of a High Electron Mobility Transistor (HEMT) is used as a time variable resistor to accomplish frequency mixing. An X-band image rejected mixer was constructed and pseudomorphic HEMTs were fabricated in order to investigate the performance. Acceptable conversion is obtained at very low LO-power. The experimental -1 dB compression point referred to the output is found to be approximately 3 dB lower than the LO-power.
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| 10. |
- Zirath, Herbert, 1955, et al.
(författare)
-
W-band subharmonically pumped resistive mixer based on pseudomorphic heterostructure field effect transistor technology
- 1993
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Ingår i: Proceedings of the 1993 IEEE MTT-S International Microwave Symposium Digest. - 0149-645X. - 0780312090 ; 1, s. 341-344
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Konferensbidrag (refereegranskat)abstract
- This paper describes the first subharmonically pumped resistive mixer (SPRM) based on HFETs, operating in the W-band (75-110 GHz). Two HFET devices, specially designed for this application, were integrated together with a coupler, 180° phase shifter, and an IF-filter. Both theoretical and experimental results are presented in this paper. A minimum conversion loss of about 22 dB was experimentally obtained at an LO-power of 10 dBm.
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