Development of 70 GHz receivers for the Planck LFI

Development of the Planck LFI 70 GHz cryogenic receiver is described. Most important components of this continuous correlation receiver, i.c., low noi se amplifiers (LNA) will be based on the InP MMIC technology using co-plana r transmission lines. First steps to obtain these LNAs and other MMICs are described. For the fabrication of the circuits either Daimler-Benz, or TRW InP processing will be used. Important part of developing the front- and ba ck-end modules will be good testing facilities for the needed circuits and devices. A unique on-wafer noise parameter testing facility at V-band is sh own as well as the present status of cryogenic on-wafer testing set-up is p resented.