<title>Design of the focal plane array receiver for the NRO 45-m telescope</title>

Abstract

The design of the new 5 X 5 SIS focal plane array receiver for the 45-m telescope at the Nobeyama Radio Observatory (NRO) is described. It is called BEARS (SIS 25-BEam Array Receiver System). This receiver has 25 elements. It covers the frequency range from 82 to 116 GHz. The array uses SIS junctions mounted in fixed tuned mixer blocks. The mean DSB receiver noise temperature is about 75 K at all the LO frequencies. The standard deviation of the receiver noise temperature is about 20 K. The receiver was installed on the telescope and has been used for observations and measurements since April 1998. The design of the receiver system, the optics and the heat model will be presented in this paper.