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Design and Development of ALMA Band 4 Cartridge Receiver
| Content Provider | Semantic Scholar |
|---|---|
| Author | Asayama, Shin’ichiro Kawashima, Susumu Iwashita, Hiroyuki Takahashi, Toshikazu Inata, Motoko Obuchi, Yoshiyuki Suzuki, Takakiyo Wada, Toru |
| Copyright Year | 2008 |
| Abstract | This paper describes the design and development of the ALMA Band 4 cartridge receiver. Band 4 is one of the ten bands that will form the ALMA Front End Receiver. It receives radiation in the 125-163 GHz frequency range in two orthogonal polarizations and down-converts the sideband separated signals to intermediate frequencies between 4 and 8 GHz. I.INTRODUCTION The Atacama Large Millimeter/Submillimeter Array (ALMA) is an international collaboration between Europe, Japan and North America, in cooperation with the Republic of Chile with its full-operation expected in 2012 [1]. Taiwan is also contributing to ALMA as a partner of Japan. ALMA will be located on the Chajnantor plain of the Chilean Andes in the District of San Pedro de Atacama, 5,000 meters above sea level. The ALMA receiver system will cover all the available atmospheric frequency windows between 30 GHz and 950 GHz. The range shall be covered in 10 bands with HEMT or SIS devices. The receiver should be modular so that one easy to install self-contained receiver should cover that one particular frequency band. These self-contained receivers are known as "cartridges". The development and production of the Band 4 cartridge receivers is one portion of the Japanese in-kind contribution to ALMA. II.RECEIVER OVERVIEW ALMA Band 4 will operate in the 125-163 GHz frequency band, which is 26 % bandwidth to the center frequency of 144 GHz. A layout of the Band 4 cartridge receiver and a photograph of the assembled cartridge are shown in Fig. 1 and Fig. 2, respectively. Band 4 receivers are made on the small 140mm diameter cartridges developed by Rutherford Appleton Laboratory (RAL). It is a dual polarization receiver, which uses an orthomode transducer (OMT) as a polarization splitter. The cartridge consists of three stages (at operating temperatures 4, 15, and 110 K) and the base-plate (which acts as a vacuum seal) at 300 K, with GFRP 10 spacers between them. The 110 K stage has the LO doublers mounted on it and heat sinks for the LO waveguide, coax cables and wiring. The 15 K stage has only heat sinks for the LO waveguide, coax cables and wiring attached. The 4 K stage has the Corrugated horn, OMT, optics support structure, sidebandseparating SIS mixer units, Cryogenic Isolators, Cryogenic HEMT Amplifiers, and heat sinks for the LO waveguide, coax cable and wiring attached. Fig.1 Layout of the ALMA Band 4 cartridge receiver. DC wire harnesses are not illustrated OMT Sideband-Separating SIS mixer Unit |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://www.nrao.edu/meetings/isstt/papers/2008/2008244249.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
