Title :
A photomixer local oscillator for a 630-GHz heterodyne receiver
Author :
Verghese, S. ; Duerr, E.K. ; McIntosh, K.A. ; Duffy, S.M. ; Calawa, S.D. ; Tong, C.-Y.E. ; Kimberk, R. ; Blundell, R.
Author_Institution :
Lincoln Lab., MIT, Lexington, MA, USA
fDate :
6/1/1999 12:00:00 AM
Abstract :
A photomixer local oscillator (LO) operating at the 630-GHz difference frequency of two laser diodes was successfully demonstrated with a heterodyne detector based on a niobium superconducting tunnel junction. The low-temperature-grown GaAs photomixer generated 0.20 μW in the input spatial mode of the receiver. Using the photomixer LO, the double-sideband noise temperature of the receiver was 331 K-in good agreement with the 323 K noise temperature obtained when a multiplied Gunn oscillator generating 0.25 μW was substituted for the photomixer.
Keywords :
III-V semiconductors; frequency stability; gallium arsenide; heterodyne detection; microwave photonics; photoconducting switches; submillimetre wave mixers; submillimetre wave oscillators; submillimetre wave receivers; superconducting microwave devices; superconductor-insulator-superconductor mixers; 0.2 muW; 630 GHz; GaAs; Nb; Nb superconducting tunnel junction; THF heterodyne receiver; double-sideband noise temperature; heterodyne detector; input spatial mode; laser diodes; local oscillator; low-temperature-grown GaAs photomixer; photomixer LO; Diode lasers; Frequency; Gallium arsenide; Gunn devices; Josephson junctions; Local oscillators; Niobium; Noise generators; Superconducting device noise; Temperature;
Journal_Title :
Microwave and Guided Wave Letters, IEEE
