Title :
Quasi-optical attenuators for ALMA band 10 receiver
Author :
Gonzalez, Alvaro ; Fujii, Yasunori ; Kaneko, Keiko ; Uzawa, Yoshinori
Author_Institution :
ALMA Band 10 Group, Nat. Astron. Obs. of Japan, Tokyo, Japan
Abstract :
Simple quasi-optical attenuators based on beam truncation have been designed, fabricated and tried on ALMA band 10 receivers (787-950 GHz) with optimal results. The design is based on physical-optics simulations considering effects of diffraction. The use of these attenuators allows flexibility in the design of the local oscillator (LO) quasi-optical injection scheme depending on the specific performance of components for each of the 73 ALMA band 10 receivers. In particular, they have proven very effective to keep system noise within the stringent ALMA requirements (230 K at 80% of 787-950 GHz band).
Keywords :
electromagnetic wave diffraction; optical attenuators; submillimetre wave oscillators; submillimetre wave receivers; ALMA band 10 receiver; Atacama large millimeter/submillimeter array; bandwidth 787 GHz to 950 GHz; beam truncation; diffraction; local oscillator; physical-optics simulation; quasioptical attenuator; quasioptical injection scheme; quasioptical waveguide; submillimeter wave technology; temperature 230 K; Attenuation; Attenuation measurement; Attenuators; Mixers; Noise; Receivers; Temperature measurement; Atacama Large Millimeter/submillimeter Array; Gaussian beams; Quasi-optical waveguides; Submillimeter wave measurements; Submillimeter wave technology;
Conference_Titel :
Microwave Conference Proceedings (APMC), 2011 Asia-Pacific
Conference_Location :
Melbourne, VIC
Print_ISBN :
978-1-4577-2034-5
