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Site selection for the Tianlai experiment proceedings of the XXXIst URSI general assembly and scientific symposium to be held in Beijing, China (CIE), August 17–23, 2014

The Tianlai project plans to build a compact cylinder array to map the 21cm emission from redshift 0 to 3, corresponding to frequency 350-1420MHz. The full array is designed to have a size of about 100m-100m in dimension. A site with minimum radio frequency interference (RFI) and convenience of logisitics support is desired. This project is also constrained by its low budget, so attention have to be paid to reduce the cost for the construction and operation. We have conducted site surveys in many places in China, obtained radio spectrum measurement at more than a hundred potential site locations. This paper describes the site selection and survey method. We have tentatively selected a site in Hongliuxia, Balikun County, Xinjiang Autonomous Region, which have very low RFI and is potentially good for other low frequency radio experiments.