This paper describes our progress in designing the K-band receiver in WIN 0.15μm GaAs pHEMT process. The LNA contains three stages of common-source transistors, and its noise performance has been optimized over the intended bandwidth; the following mixer is made of single-balanced transistors where the edge-coupled Marchand balun provides the required 18∼26GHz differential-mode LO while active balun is used for combining the 8GHz IF signals. The conversion gain measured on-wafer at room temperature is around 20dB and the noise temperature is close to 300K, with overall power consumption 140mW, and the chip area is 1000×2500μm2. A close inspection on the wide-IF-band noise measurement procedure is also provided where the impact of conversion gain on the measured Tn is explored. This receiver circuit will facilitate the construction of large focal plane arrays where compact cryogenic receiver module is in urgent demand.