Intersatellite laser interferometers feature quadrant photoreceivers to produce electrical signals from the interfered optical beams. In the particular case of LISA, the expected optical AC beat note has an amplitude of the order of nW. This requires photoreceivers with an input current noise density of a few pA Hz–1/2 in each channel up to 25MHz. Additionally, the significant number of photoreceivers in a single spacecraft imposes tight constraints on the power consumption per device. We present the experimental characterization of a quadrant photoreceiver based on discrete heterojunction bipolar transistors and an off-the-shelf 0.5 mm diameter InGaAs quadrant photodiode, showing an input current noise density of 1:9 pA Hz–1/2 at 25MHz, a 3 dB bandwidth of 37MHz and a total power consumption of 178mW. CCBY