An Integrated System at the Bleien Observatory for Mapping the Galaxy
  We describe the design and performance of the hardware system at the Bleien
Observatory. The system is designed to deliver a map of the Galaxy for studying
the foreground contamination of low-redshift (z=0.13--0.43) H$_{\rm I}$
intensity mapping experiments as well as other astronomical Galactic studies.
This hardware system is composed of a 7m parabolic dish, a dual-polarization
corrugated horn feed, a pseudo correlation receiver, a Fast Fourier Transform
spectrometer, and an integrated control system that controls and monitors the
progress of the data collection. The main innovative designs in the hardware
are (1) the pseudo correlation receiver and the cold reference source within
(2) the high dynamic range, high frequency resolution spectrometer and (3) the
phase-switch implementation of the system. This is the first time these
technologies are used together for a L-band radio telescope to achieve an
electronically stable system, which is an essential first step for wide-field
cosmological measurements. This work demonstrates the prospects and challenges
for future H$_{\rm I}$ intensity mapping experiments.
