A 110–118‐GHz receiver based on a superconducting quasiparticle tunnel junction mixer is described. The single‐sideband noise temperature is as low as 68±3 K. This is nearly twice the sensitivity of any other receiver at this frequency. The receiver was designed using a low‐frequency scale model in conjunction with the quantum mixer theory. A scaled version of the receiver for operation at 46 GHz has a single‐sideband noise temperature of 55 K. The factors leading to the success of this design are discussed.