Design of a fully HBT 40GS/s sampling circuit for very large bandwidth non repetitive signal analysis

The design of a fully heterojunction bipolar transistor (HBT) circuit allowing 20GHz bandwidth random signal sampling and the experimental results of the basic circuits are discussed. Assuming a temporal analysis depth of 5ns, this circuit, based on the principle of non simultaneous spatial sampling can reach, in a single shot mode, a truly sampling frequency of 40GS/s. Its realization, led through several InP HBT MMIC (F/sub T/=180GHz) and CPW propagation line permits to meet the main requirements in terms of bandwidth, dynamic range and jitter.