Design and Performance of ALMA Band 1 Receiver and its Future Prospects

ALMA Band 1 receiver covering 35-50 GHz is with the largest relative bandwidth among ten ALMA bands. The Band 1 receiver front-end cartridges are now in preproduction stage. Even with the large noise contribution from the warm optics (5-11 K), the first three Band 1 cartridges still exhibit state-of-the-art receiver noise temperature of 16-31 K for any combination of the RF and LO frequencies. In the presentation, we will not only present the Band 1 receiver design and system performance, but also discuss the future prospects to further enhance its performance and capabilities with lower receiver noise temperature, wider RF and IF frequency coverage, focal plane array configuration, and digital signal processing.