Development of Low-Noise Submillimeter-Wave Mixers with Quasi-Optical Beam
Grant-in-Aid for Developmental Scientific Research
|Allocation Type||Single-year Grants |
|Research Institution||Kisarazu National College of Technology (K.N.C.T) |
KODAIRA Shinji (1988) Professor, Department of Electrical Engineering, Kisarazu National College of Technology, 電気工学科, 教授 (50042627)
小平 真次 (1987) 木更津工業高専, 助教授
INATANI Junji Associate Professor, Nobeyama Radio Observatory, National Astronomical Observato, 助教授 (20134629)
NAKAMURA Tsuyosi Professor, Natural Science Education, Kisarazu National College of Technology, 基礎学系, 教授 (50042619)
|Project Period (FY)
1987 – 1988
Completed (Fiscal Year 1988)
|Budget Amount *help
¥10,100,000 (Direct Cost: ¥10,100,000)
Fiscal Year 1988: ¥5,000,000 (Direct Cost: ¥5,000,000)
Fiscal Year 1987: ¥5,100,000 (Direct Cost: ¥5,100,000)
|Keywords||Quasi-optical / Printed antenna / Spiral antenna / Mixer / SIS / SWL / Submillimeter / 電子ビーム露光 / ミキサー|
Advance of radio astronomy into the submillimeter region requires low-nise super- heterodyne receivers. System noise temperature is almost decided by a submillimeter wave mixer. In this re-search from 1987 to 1988, Josephson mixers with a quasi-optical beam have been developed for astronmical observations.
The main results are:
1) A bow tie antenna and a printed spiral antenna were tried as a feed antenna for the mixer. Parameters of the spiral antenna were measured by using a scaled model or 100 of 200 multiplica-tion.
2) RF matching circuits between the antenna and Josephson junctions were simulated and got a good result of 60 GHz bandwidth at 337 GHz. IF matching circuits between the Josephson junctions and IF amplifier were also designed.
3) The hyper-hemispherical lens was simulated to get a optimum condition of frequency independent image mathcing of a Gaussian beam.
4) Submillimeter Josephson mixers with the quasi-optical beam were made after researching for fabricating process of a SIS junction with a small area and a SWL junction by using a elctron beam exposure equipment.
5) The mixers were assembled into a submillimeter cryogenically cooled receiver for a low-noise measurment system. As a result, system noise temperature have reached about 300 k at 338 GHz.
In addition to these results, we have found
6) Coherent operation for the mixer was observed in the series Josephson Junctions at the frequency of submillimeter wave region.
But next subjects have occurred for future problems as
1) A handy, stable and sweepable oscillator should be developed for submillimeter wave region.
2) Josephson Junction with high current density and a small junction area should be investigated.
Report (2 results)
Research Products (18 results)