Abstract: The present disclosure relates to semiconductor structures and, more particularly, to a bipolar transistor and methods of manufacture. The structure includes: a collector region in a semiconductor substrate; a base region adjacent to the collector region; and an emitter extending above the base region and comprising semiconductor material and a hardmask surrounding a lower portion of the semiconductor material.

Abstract: A radar detection system includes a transmitter and a receiver. The transmitter generates a pulse including a first subpulse generated at a first predetermined frequency and a second subpulse generated at a second predetermined frequency. At least one of the first and second subpulses include a digitally adjusted rise time and fall time, each of the rise time and fall time being separately adjustable independent of the other to provide for the relative lowering of transmission power above and below the first and second predetermined frequencies. The transmitter then transmits generated first and second subpulses at the respective first and second predetermined frequencies, as digitally adjusted in rise and fall time.