BINGO: a single dish approach to 21cm intensity mapping
  BINGO is a concept for performing a 21cm intensity mapping survey using a single dish telescope. We briefly discuss the idea of intensity mapping and go on to define our single dish concept. This involves a \sim 40 m dish with an array of \sim 50 feed horns placed \sim 90 m above the dish using a pseudo-correlation detection system based on room temperature LNAs and one of the celestial poles as references. We discuss how such an array operating between 960 and 1260 MHz could be used to measure the acoustic scale to 2.4% over the redshift range 0.13<z<0.48 in around 1 year of on-source integration time by performing a 10 deg \times 200 deg drift scan survey with a resolution of \sim 2/3 deg. 
R. A. Battye, M. L. Brown, I. W. A. Browne, R. J. Davis, P. Dewdney,   C. Dickinson, G. Heron, B. Maffei, A. Pourtsidou, P. ...
astro-ph.CO