Microwave active solid state cold/warm noise source

Details Microwave active solid state cold/warm noise source Microwave active solid state cold/warm noise source

1997-11-04

2000-10-24

Hellner, Mark

Communications: directive radio wave systems and devices (e.g.,

Directive

Including a radiometer

342174, G01S 302

Patent

active

061374407

ABSTRACT:
A microwave active noise source and method used for calibrating a radiometer includes a transistor configured as a noise equivalent model having a gate port, drain port and source port. During calibration of the radiometer the drain port is terminated and a bias circuit applies DC bias to the noise equivalent model. The bias circuit controls the DC bias such that a hot thermal radiation temperature and a cold thermal radiation temperature are alternately generated at the gate port of the noise equivalent model. A source inductance coupled to the source port of the noise equivalent model provides series feedback. To match the impedances in the noise source, an output matching impedance network is connected to the drain port and an input matching impedance network is connected to the gate port of the noise equivalent model. The input matching impedance network includes an input port for outputting the hot and cold thermal radiation temperatures used to calibrate the radiometer.

REFERENCES:
patent: 3235731 (1966-02-01), Seling
patent: 3263230 (1966-07-01), Greenberg
patent: 3380055 (1968-04-01), Fow et al.
patent: 3409827 (1968-11-01), Goggings, Jr.
patent: 3525037 (1970-08-01), Madden, et al
patent: 3564420 (1971-02-01), Webb
patent: 3628151 (1971-12-01), Roeder
patent: 3638494 (1972-02-01), Broussaud et al.
patent: 3693095 (1972-02-01), Wilt
patent: 3735405 (1973-05-01), Berg
patent: 3737905 (1973-06-01), Haroules et al.
patent: 3748904 (1973-07-01), Ford
patent: 3777270 (1973-12-01), Hardy, et al.
patent: 4081679 (1978-03-01), Cohn
patent: 4272731 (1981-06-01), Day, et al.
patent: 4527162 (1985-07-01), Strickland
patent: 4568200 (1986-02-01), Hatono et al.
patent: 5047783 (1991-09-01), Hugenin
patent: 5128884 (1992-07-01), Prager
patent: 5231404 (1993-07-01), Gasiewski
patent: 5270528 (1993-12-01), Ogikubo
patent: 5354325 (1994-10-01), Chive, et al .
patent: 5688050 (1997-11-01), Sterzer, et al.
"A Table-Based Bias and Temperature-Department Small-Signal and Noise Equivalent Circuit Model ", Peter B. Winson, Steven M. Lardizabal and Lawrence Dunleavy, IEEE Transactions on Microware Theory and Techniques, vol. 45, No. 1, Jan. 1997, pp. 46-51.
"The United Kingdom National Standard of Microware Noise at 4-1 GHz and 77K", D.J. Blundell, Journal of Physics Scientific Instruments, 1975 vol. 8.

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