CDL Timeline

1968 Parametric amplifier receiver for L-band on 140-ft telescope. (Edrich)

1974 Introduction of cryogenic Schottky diode mixers for radio astronomy. (Weinreb, Kerr)

1976 First use of circular overmoded waveguide signal and LO transmission system for the VLA. (Weinreb, Predmore, Ogai, Parrish)

1979 200-GHz mixer receiver with solid-state local oscillator. First Schottky diode frequency multiplier local oscillator. (Weinreb, Pospieszalski)

1980s VLBA tape recorder patented. (Escoffier)

1985 First measurement of noise parameters of GaAs heterostructure FETs (HFETs) at cryogenic temperatures. (Pospieszalski, Weinreb)

1985-1988 Development of AlGaAs/GaAs HFETs and X-band amplifiers with record-breaking noise performance for the Voyager-Neptune Project (Weinreb, Pospieszalski)

1986 Noise parameter measurement method for FETs at cryogenic temperatures (Pospieszalski)

1986 Determination of noise equivalent circuit of isolator (Pospieszalski)

1988 Introduction of Nb SIS mixers for radio astronomy (Kerr, Pan, UVA)

1989 Development of noise model of FETs and HFETs, now known as Pospieszalski noise model (Pospieszalski)

1991 First MMIC millimeter-wave frequency multiplier (Bradley, Weinreb, Mattauch)

1992 Development of the broadband tunerless SIS mixer (Kerr & Pan)

1993 First W-band MMIC amplifier demonstrated (Pospieszalski, Pan, Wang)

1993 Demonstration of low noise performance of cryogenic InP HFET (Pospieszalski)

1996-1999 Amplifiers and radiometers for WMAP (Pospieszalski, Wollack)

1996 Development of wideband phase shifter for cryogenically cooled receivers (Srikanth) [38]

1998 First beam-forming array for radio astronomy (Bradley, Fisher)

1998 Full waveguide band circular polarizer (Srikanth)

1998 Single-chip sideband-separating SIS mixer (Kerr, Pan, JPL)

2000 Single-chip balanced SIS mixer (Kerr, Pan, UVA)

2002 Patent for high-level broadband noise source for mm/sub-mm wavelengths. (Pan)

2003 Wide band (2:1) compact corrugated horns developed for EVLA secondary focus.

2005 ALMA correlator. 64 antennas, 8,192 spectral points, 16,000 MHz bandwidth. (Escoffier, Comoretto, Webber, Baudry, Broadwell, Greenberg, Treacy, Cais, Quertier, Camino, Bos, Gunst)

2006 Superconducting 4-12 GHz 180-degree hybrid on a small chip for use in balanced SIS mixers. (Kerr)

2007 75-110 GHz corrugated waveguide phase shifter. (Srikanth)

2009 Development of compact full waveguide band (8-12 GHz) turnstile junction orthomode transducer. (Srikanth)

2009 Word-boundary detection in a serialized gaussian-distributed white-noise data stream patented. (Morgan, Fisher)

2010 Establishment of limits on allowable noise parameters of microwave transistors

2011 Patented new class of reflectionless filter. (Morgan)

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