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Jiang, L., Zhang, W., Yao, Q. J., Lin, Z. H., Li, J., Shi, S. C., et al. (2005). Characterization of a quasi-optical NbN superconducting hot-electron bolometer mixer. In Proc. PIERS (Vol. 1, pp. 587–590).
Abstract: In this paper, we report the performance of a quasi-optical NbN superconducting HEB (hot electron bolome-ter) mixer measured at 500 GHz. The quasi-optical NbN superconducting HEB mixer is cryogenically cooled bya 4-K close-cycled refrigerator. Its receiver noise temperature and conversion gain are thoroughly investigatedfor different LO pumping levels and dc biases. The lowest receiver noise temperature is found to be approxi-mately 1200 K, and reduced to about 445 K after correcting theloss of the measurement system. The stabilityof the mixer’s IF output power is also demonstrated.
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Yagoubov, P., van de Stadt, H., Hoogeveen, R., Koshelets, V., Birk, M., & Murk, A. (2005). OPTICAL DESIGN OF SUB-MILLIMETER SPECTROMETER FOR LIMB SOUNDER. International Symposium on Space Terahertz Technology, .
Abstract: TELIS (Terahertz and submm Limb Sounder) is a cooperation between DLR (Institute for Remote Sensing Technology, Germany), RAL (Rutherford Appleton Laboratories, UK) and SRON (National Institute for Space Research, the Netherlands), to build a three-channel balloon-borne heterodyne spectrometer for atmospheric research. The three receivers will operate simultaneously at 500 GHz (channel developed by RAL), at 550-650 GHz (SRON in collaboration with IREE), and at 1.8 THz (DLR). The balloon platform on which TELIS will fly also contains a Fourier transform spectrometer: MIPAS-B developed by the IMK (Institute of Meteorology and Climate research of the University of Karlsruhe, Germany). MIPAS-B will simultaneously measure within the range 680 to 2400 cm-1. The combination of the TELIS and MIPAS instruments will provide an unprecedented wealth of scientific data and will also be used to validate other instruments and atmospheric chemistry models. In this paper we present the optical design of TELIS with an emphasis on the 550-650 GHz channel. The main design goal was to generate a high efficiency antenna beam over the full frequency range, with low side lobes and close to diffraction limited angular resolution in the vertical direction at the sky. All these requirements had to be achieved within a small volume and low mass. Design and validation of the optics, as well as estimation of optical components tolerances, was done using commercial software packages ZEMAX and GRASP.
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de Graauw, T., Caux, E., Guesten, R., Helmich, F., Pearson, J., Phillips, T. G., et al. (2005). The Herschel-heterodyne instrument for the far-infrared (HIFI). In Bulletin of the American Astronomical Society (1219). Bulletin of the American Astronomical Society, 37.
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Cherednichenko, S., Kollberg, E., Angelov, I., Drakinskiy, V., Berg, T., & Merkel, H. (2005). Effect of the direct detection effect on the HEB receiver sensitivity calibration. In Proc. 16th Int. Symp. Space Terahertz Technol. (pp. 235–239). Göteborg, Sweden.
Abstract: We analyze the scale of the HEB receiver sensitivity calibration error caused by the so called “direct detection effect”. The effect comes from changing of the HEB parameters when whey face the calibration loads of different temperatures. We found that for HIFI Band 6 mixers (Herschel Space Observatory) the noise temperature error is of the order of 8% for 300K/77K loads (lab receiver) and 2.5% for 100K/10K loads (in HIFI). Using different approach we also predict that with an isolator between the mixer and the low noise amplifiers the error can be much smaller.
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Karpov, A., Miller, D., Stern, J. A., Bumble, B., LeDuc, H. G., & Zmuidzinas, J. (2005). Low noise NbTiN 1.25 THz SIS mixer for Herschel Space Observatory. In Proc. 16th Int. Symp. Space Terahertz Technol. (450). Göteborg, Sweden.
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